Quinazoline derivatives suitable for use as werner syndrome helicase protein inhibitors

Abstract

The present invention relates to compounds of the Formula I, and pharmaceutically salts thereof: I wherein RS, R1, R2, R3, R4 and X are each as defined herein. The compounds of the present invention inhibit WRN. The novel therapeutic compounds are therefore useful for the treatment and / or prevention of diseases and conditions in which WRN activity is implicated, such as, for example but not limited to, the treatment and / or prevention of cancer. The present invention also relates to pharmaceutical compositions comprising the novel therapeutic compounds defined herein, to processes for synthesising these compounds and to their use for the treatment of diseases and / or conditions in which WRN activity is implicated.

Description

P383145WO June 2025 1 NOVEL COMPOUNDS, COMPOSITIONS AND THERAPEUTIC USES THEREOF INTRODUCTION

[0001] The present invention relates to novel therapeutic compounds. More specifically, the present invention relates to novel therapeutic compounds that inhibit Werner syndrome helicase protein (WRN, RECQ3). The novel therapeutic compounds are therefore useful for the treatment and / or prevention of diseases and conditions in which WRN activity is implicated, such as, for example but not limited to, the treatment and / or prevention of cancer. The present invention also relates to pharmaceutical compositions comprising the novel therapeutic compounds defined herein, to processes for synthesising these compounds and to their use for the treatment of diseases and / or conditions in which WRN activity is implicated. BACKGROUND OF THE INVENTION

[0002] Microsatellite instability (MSI) is a genomic abnormality that plays a crucial role in the development and progression of various types of cancer, including endometrial (31.4%), colorectal (15%), gastric (15%) and ovarian cancers (12%) (Boland et al, 2010; Bonneville et al, 2017; zhang et al, 2020). It is characterized by the accumulation of changes in repetitive DNA sequences known as microsatellites.

[0003] The stability of the microsatellite repeats through DNA replication is maintained by a DNA repair mechanism called DNA mismatch repair (MMR) (Aaltonen et al; 1993). Mutation or silencing of MMR genes, including MLH1, MSH2, MSH6 and PMS2 leads to disruption of microsatellite repeat sequence integrity, through small insertions or deletions. This results in an MSI phenotype, characterized by changes in the length of these repetitive sequences (Li et al, 2020). This phenotype can be assessed through molecular testing of specific microsatellites, or immunohistochemical evaluation of MMR protein expression (van Wietmarschen et al., 2020). One of the key clinical implications of high microsatellite instability (MSI-H), besides its high prevalence in different cancers, lies in its predictive value for response to immunotherapy. However, while checkpoint inhibitors have been shown to lead to longer proliferation free survival than chemotherapy for metastatic MSI-H colorectal cancer (André et al 2020), 30-35% of patients still fail to derive any benefit from immune response inhibitors and many other patients develop resistance (Roth et al 2021), indicating a clear clinical need.P383145WO June 2025 2

[0004] The Werner syndrome helicase protein (RECQ3, WRN) functions as a DNA helicase and exonuclease, unwinding double-stranded DNA structures and resolving secondary DNA structures during replication, damage repair and recombination processes. It therefore plays a crucial role in maintaining the integrity of the genome (Rossi et al., 2010). Deficiencies or dysfunctions in WRN have been associated with genomic instability, accelerated aging and increased susceptibility to cancer development (Crabbe L. et al., 2004). Recently, WRN has been shown by independent groups to be essential in MSI-High tumour cells (Behan et al, 2019; Chan et al 2019). The WRN helicase is required to unwind the secondary DNA structures that form within the abnormally expanded microsatellite repeats, such as hairpin loops and cruciform structures. In the absence of WRN these secondary structures undergo nuclease cleavage resulting in increased DNA double-strand breaks (DSBs), chromosome breakage, mitotic failures and subsequent growth arrest and cell death (van Wietmarschen N. et al., 2020).

[0005] In conclusion, microsatellite instability is a common genomic abnormality in cancer that arises from defects in the DNA mismatch repair system and targeting the helicase activity of WRN represents a promising therapeutic approach for those MSI-High cancers. Furthermore, the broader implications of WRN's global DNA metabolism activity suggest its potential as a therapeutic target in various cancer contexts.

[0006] There is therefore a need to provide novel therapeutics that can effectively target and inhibit WRN activity.

[0007] The present invention was devised with the foregoing in mind. References Aaltonen L.A. et al. Clues to the pathogenesis of familial colorectal cancer, Science.1993 May 7;260(5109):812-6. André T. et al. Pembrolizumab in Microsatellite-Instability-High Advanced Colorectal Cancer, N Engl J Med.2020 Dec 3;383(23):2207-2218. Behan F.M. et al. Prioritization of cancer therapeutic targets using CRISPR-Cas9 screens, Nature.2019 Apr;568(7753):511-516 Boland C.R. et al. Microsatellite instability in colorectal cancer, Gastroenterology.2010 Jun;138(6):2073-2087.e3 Bonneville R. et al. Landscape of Microsatellite Instability Across 39 Cancer Types, JCO Precis Oncol.2017; 2017:PO.17.00073P383145WO June 2025 3 Chan M.E. et al. WRN helicase is a synthetic lethal target in microsatellite unstable cancers. Nature.2019 Apr;568(7753):551-556 Crabbe L. et al. Defective telomere lagging strand synthesis in cells lacking WRN helicase activity, Science.2004 Dec 10;306(5703):1951-3 Li K. et al. Microsatellite instability: a review of what the oncologist should know, Cancer Cell Int.2020 Jan 13;20:16 Rossi M.L. et al. Roles of Werner Syndrome Protein in Protection of Genome Integrity, DNA Repair.2010 Mar 2; 9(3): 331–344. Roth, M.T. et al. Pembrolizumab in unresectable or metastatic MSI-high colorectal cancer: safety and efficacy, Expert Rev Anticancer Ther.2021 Feb; 21(2): 229–238. Van Wietmarschen N. et al. Repeat expansions confer WRN dependence in microsatellite- unstable cancers, Nature.2020 Oct;586(7828):292-298. Zhang C. et al. Incidence and detection of high microsatellite instability in colorectal cancer in a Chinese population: a meta-analysis, J Gastrointest Oncol.2020; 11(6):1155-1163 SUMMARY OF THE INVENTION

[0008] In one aspect, the present invention provides a compound of Formula I as defined herein, and / or a pharmaceutically acceptable salt, hydrate or solvate thereof.

[0009] In another aspect, the present invention provides a pharmaceutical composition which comprises a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, and one or more pharmaceutically acceptable excipients.

[0010] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in therapy.

[0011] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of a disease or condition in which WRN activity is implicated.

[0012] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceuticalP383145WO June 2025 4 composition as defined herein, for use in the treatment of a disease or condition associated with aberrant activity of WRN.

[0013] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of cancer or benign neoplasms.

[0014] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of a cancer.

[0015] In another aspect, the present invention provides the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of a disease or condition in which WRN activity is implicated.

[0016] In another aspect, the present invention provides the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of a disease or condition associated with aberrant activity of WRN.

[0017] In another aspect, the present invention provides the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of cancer or benign neoplasms.

[0018] In another aspect, the present invention the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of a cancer.

[0019] In another aspect, the present invention provides a method of treating a disease or condition in which WRN activity is implicated, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.

[0020] In another aspect, the present invention provides a method of treating a disease or condition associated with aberrant activity of WRN, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.P383145WO June 2025 5

[0021] In another aspect, the present invention provides a method of treating cancer or benign neoplasms, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.

[0022] In another aspect, the present invention provides a method of treating cancer, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.

[0023] In another aspect, the present invention provides a combination treatment comprising a compound of Formula I, or a pharmaceutically acceptable salt, hydrate or solvate thereof, as defined herein, with one or more additional therapeutic agents.

[0024] In another aspect, the present invention provides processes for preparing compounds of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, as defined herein, with one or more additional therapeutic agents.

[0025] In a further aspect, the present invention provides the use of a compound of Formula I or a salt, hydrate or solvate thereof, for CRISPR gene editing in vitro or in vivo.

[0026] In another aspect, the present invention provides the use of a compound of Formula I or a salt, hydrate or solvate thereof, for increasing the efficiency of CRISPR gene editing in vitro or in vivo.

[0027] In another aspect, the present invention provides a compound of Formula I, or a salt, hydrate or solvate thereof, for use in CRISPR gene editing in vivo.

[0028] In another aspect, the present invention provides a compound of Formula I, or a salt, hydrate or solvate thereof, for use in increasing the efficiency of CRISPR gene editing in vivo.

[0029] Preferred, suitable, and optional features of any one particular aspect of the present invention are also preferred, suitable, and optional features of any other aspect. DETAILED DESCRIPTION OF THE INVENTION Definitions

[0030] Unless otherwise stated, the following terms used in the specification and claims have the following meanings set out below.

[0031] It is to be appreciated that references to “treating” or “treatment” include prophylaxisP383145WO June 2025 6 as well as the alleviation of established symptoms of a condition. “Treating” or “treatment” of a state, disorder or condition therefore includes: (1) preventing or delaying the appearance of clinical symptoms of the state, disorder or condition developing in a human that may be afflicted with or predisposed to the state, disorder or condition but does not yet experience or display clinical or subclinical symptoms of the state, disorder or condition, (2) inhibiting the state, disorder or condition, i.e., arresting, reducing or delaying the development of the disease or a relapse thereof (in case of maintenance treatment) or at least one clinical or subclinical symptom thereof, or (3) relieving or attenuating the disease, i.e., causing regression of the state, disorder or condition or at least one of its clinical or subclinical symptoms.

[0032] A “therapeutically effective amount” means the amount of a compound that, when administered to a mammal for treating a disease, is sufficient to effect such treatment for the disease. The "therapeutically effective amount" will vary depending on the compound, the disease and its severity and the age, weight, etc., of the mammal to be treated.

[0033] References to “WRN” refer to Werner syndrome helicase protein (WRN, RECQ3).

[0034] The compounds and intermediates described herein may be named according to either the IUPAC (International Union for Pure and Applied Chemistry) or CAS (Chemical Abstracts Service) nomenclature systems. It should be understood that unless expressly stated to the contrary, the terms “compounds of Formula I”, “compounds of the invention” and the more general term “compounds” refer to and include any and all compounds described by and / or with reference to Formula I herein. It should also be understood that these terms encompasses all stereoisomers, i.e. cis and trans isomers, as well as optical isomers, i.e. R and S enantiomers, of such compounds, in substantially pure form and / or any mixtures of the foregoing in any ratio. This understanding extends to pharmaceutical compositions and methods of treatment that employ or comprise one or more compounds of the Formula I, either by themselves or in combination with additional agents.

[0035] Unless specified otherwise, atoms are referred to herein by their chemical symbol as appearing in the IUPAC periodic table of the Elements. For example, “C” refers to a carbon atom.

[0036] The term "(m-nC)" or "(m-nC) group" used alone or as a prefix, refers to any group having m to n carbon atoms.

[0037] In this specification the term “alkyl” includes both straight and branched chain alkyl groups. References to individual alkyl groups such as “propyl” are specific for the straight chain version only and references to individual branched chain alkyl groups such as “isopropyl” are specific for the branched chain version only. For Example, “(1-6C)alkyl” includes (1-P383145WO June 2025 7 4C)alkyl, (1-3C)alkyl, propyl, isopropyl and t-butyl. A similar convention applies to other radicals, for example “phenyl(1-6C)alkyl” includes phenyl(1-4C)alkyl, benzyl, 1-phenylethyl and 2-phenylethyl.

[0038] An “alkylene” group is an alkyl group that is positioned between and serves to connect two other chemical groups. Thus, “(1-6C)alkylene” means a linear saturated divalent hydrocarbon radical of one to six carbon atoms or a branched saturated divalent hydrocarbon radical of three to six carbon atoms, for example, methylene, ethylene, propylene, 2- methylpropylene, pentylene, and the like.

[0039] “(3-6C)cycloalkyl” means a hydrocarbon ring containing from 3 to 6 carbon atoms, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or bicyclo[2.2.1]heptyl.

[0040] The term “halo” or “halogeno” refers to fluoro, chloro, bromo and iodo.

[0041] As used herein by themselves or in conjunction with another term or terms, “haloalkyl” and “haloalkyl group” refer to alkyl groups in which one or more hydrogen atoms are replaced by halogen atoms. Representative examples include, but are not limited to, –CF3, –CHF2, –CH2F, –CF2CF3, –CHFCF3, and –CH2CF3. Suitably, a haloalkyl group is selected from –CHF2and –CF3, suitably –CF3.

[0042] As used herein by themselves or in conjunction with another term or terms, “haloalkoxy” and “haloalkoxy group” refer to alkoxy groups (i.e. O-alkyl groups) in which one or more hydrogen atoms are replaced by halogen atoms. Representative examples include, but are not limited to, –OCF3, –OCHF2, –OCH2F, and –OCF2CF3. Suitably, a haloalkyoxy group is selected from –OCHF2 and –OCF3, suitably –OCF3.

[0043] The term “heterocyclyl”, “heterocyclic” or “heterocycle” means a non-aromatic saturated or partially saturated monocyclic, fused, bridged, or spiro bicyclic heterocyclic ring system(s). Monocyclic heterocyclic rings contain from about 3 to 12 (suitably from 3 to 7) ring atoms, with from 1 to 5 (suitably 1, 2 or 3) heteroatoms selected from nitrogen, oxygen or sulfur in the ring. Bicyclic heterocycles contain from 7 to 17 member atoms, suitably 7 to 12 member atoms, in the ring. Bicyclic heterocyclic(s) rings may be fused, spiro, or bridged ring systems. Examples of heterocyclic groups include cyclic ethers such as, but not limited to, oxiranyl, oxetanyl, tetrahydrofuranyl, dioxanyl, and substituted cyclic ethers. Heterocycles containing nitrogen include, for example, azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl, tetrahydrotriazinyl, tetrahydropyrazolyl, and the like. Typical sulfur containing heterocycles include tetrahydrothienyl, dihydro-1,3-dithiol, tetrahydro-2H-thiopyran, and hexahydrothiepine. Other heterocycles include dihydrooxathiolyl, tetrahydrooxazolyl,P383145WO June 2025 8 tetrahydro-oxadiazolyl, tetrahydrodioxazolyl, tetrahydrooxathiazolyl, hexahydrotriazinyl, tetrahydrooxazinyl, morpholinyl, thiomorpholinyl, tetrahydropyrimidinyl, dioxolinyl, octahydrobenzofuranyl, octahydrobenzimidazolyl, and octahydrobenzothiazolyl. For heterocycles containing sulfur, the oxidized sulfur heterocycles containing SO or SO2groups are also included. Examples include the sulfoxide and sulfone forms of tetrahydrothienyl and thiomorpholinyl such as, but not limited to, tetrahydrothiene 1,1-dioxide and thiomorpholinyl 1,1-dioxide. A suitable value for a heterocyclyl group which bears 1 or 2 oxo (=O) or thioxo (=S) substituents is, for example, 2-oxopyrrolidinyl, 2-thioxopyrrolidinyl, 2-oxoimidazolidinyl, 2-thioxoimidazolidinyl, 2-oxopiperidinyl, 2,5-dioxopyrrolidinyl, 2,5-dioxoimidazolidinyl or 2,6- dioxopiperidinyl. Particular heterocyclyl groups are saturated monocyclic 3 to 7 membered heterocyclyls containing 1, 2 or 3 heteroatoms selected from nitrogen, oxygen or sulfur, for example azetidinyl, tetrahydrofuranyl, tetrahydropyranyl, pyrrolidinyl, morpholinyl, tetrahydrothienyl, tetrahydrothienyl 1,1-dioxide, thiomorpholinyl, thiomorpholinyl 1,1-dioxide, piperidinyl, homopiperidinyl, piperazinyl or homopiperazinyl. As the skilled person would appreciate, any heterocycle may be linked to another group via any suitable atom, such as via a carbon or nitrogen atom. However, reference herein to piperidino or morpholino refers to a piperidin-1-yl or morpholin-4-yl ring that is linked via the ring nitrogen.

[0044] By “bridged ring systems” is meant ring systems in which two rings share more than two atoms, see for example Advanced Organic Chemistry, by Jerry March, 4thEdition, Wiley Interscience, pages 131-133, 1992. Examples of bridged heterocyclyl ring systems include, aza-bicyclo[2.2.1]heptane, 2-oxa-5-azabicyclo[2.2.1]heptane, aza-bicyclo[2.2.2]octane, aza- bicyclo[3.2.1]octane and quinuclidine.

[0045] By “spiro bicyclic ring systems” we mean that the two ring systems share one common spiro carbon atom, i.e. the heterocyclic ring is linked to a further carbocyclic or heterocyclic ring through a single common spiro carbon atom. Examples of spiro ring systems include 6- azaspiro[3.4]octane, 2-oxa-6-azaspiro[3.4]octane, 2-azaspiro[3.3]heptanes, 2-oxa-6- azaspiro[3.3]heptanes, 7-oxa-2-azaspiro[3.5]nonane, 6-oxa-2-azaspiro[3.4]octane, 2-oxa-7- azaspiro[3.5]nonane and 2-oxa-6-azaspiro[3.5]nonane.

[0046] The term “heteroaryl” or “heteroaromatic” means an aromatic mono-, bi-, or polycyclic ring incorporating one or more (for example 14, particularly 1, 2 or 3) heteroatoms selected from nitrogen, oxygen or sulfur. The term heteroaryl includes both monovalent species and divalent species. Examples of heteroaryl groups are monocyclic and bicyclic groups containing from five to twelve ring members, and more usually from five to ten ring members. The heteroaryl group can be, for example, a 5- or 6-membered monocyclic ring or a 9- or 10-P383145WO June 2025 9 membered bicyclic ring, for example a bicyclic structure formed from fused five and six membered rings or two fused six membered rings. Each ring may contain up to about four heteroatoms typically selected from nitrogen, sulfur and oxygen. Typically, the heteroaryl ring will contain up to 3 heteroatoms, more usually up to 2, for example a single heteroatom. In one embodiment, the heteroaryl ring contains at least one ring nitrogen atom. The nitrogen atoms in the heteroaryl rings can be basic, as in the case of an imidazole or pyridine, or essentially non-basic as in the case of an indole or pyrrole nitrogen. In general, the number of basic nitrogen atoms present in the heteroaryl group, including any amino group substituents of the ring, will be less than five.

[0047] Examples of heteroaryl include furyl, pyrrolyl, thienyl, oxazolyl, isoxazolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, 1,3,5-triazenyl, benzofuranyl, indolyl, isoindolyl, benzothienyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, benzothiazolyl, indazolyl, purinyl, benzofurazanyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, cinnolinyl, pteridinyl, naphthyridinyl, carbazolyl, phenazinyl, benzisoquinolinyl, pyridopyrazinyl, thieno[2,3b]-furanyl-, 2H-furo[3,2b]-pyranyl-, 5H-pyrido[2,3-d]-ooxazinyl-, 1H-pyrazolo[4,3-d]-oxazolyl, 4H-imidazo[4,5d]thiazolyl, pyrazino[2,3d]pyridazinyl, -imidazo[2,1b]thiazolyl, -imidazo[1,2b][1,2,4]-triazinyl. “Heteroaryl” also covers partially aromatic bi- or polycyclic ring systems wherein at least one ring is an aromatic ring and one or more of the other ring(s) is a nonaromatic, saturated or partially saturated ring, provided at least one ring contains one or more heteroatoms selected from nitrogen, oxygen or -sulfur-. Examples of partially aromatic heteroaryl groups include for example, tetrahydroisoquinolinyl, tetrahydroquinolinyl, 2-oxo-1,2,3,4-tetrahydroquinolinyl, dihydrobenzthienyl, dihydrobenzfuranyl, 2,3-dihydro-benzo[1,4]dioxinyl, benzo[1,3]dioxolyl, 2,2-dioxo-1,3-dihydro-2-benzothienyl, 4,5,6,7-tetrahydrobenzofuranyl, indolinyl, 1,2,3,4-tetrahydro-1,8-naphthyridinyl, 1,2,3,4-tetrahydropyrido[2,3-b]pyrazinyl, 3,4-dihydro-2H-pyrido[3,2-b][1,4]oxazinyl and 6,8-dihydro-5H-[1,2,4]triazolo[4,3-a]pyrazinyl.

[0048] Examples of five membered heteroaryl groups include but are not limited to pyrrolyl, furanyl, thienyl, imidazolyl, furazanyl, oxazolyl, oxadiazolyl, oxatriazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, triazolyl and tetrazolyl groups.

[0049] Examples of six membered heteroaryl groups include but are not limited to pyridyl, pyrazinyl, pyridazinyl, pyrimidinyl and triazinyl.

[0050] A bicyclic heteroaryl group may be, for example, a group selected from: a benzene ring fused to a 5- or 6-membered ring containing 1, 2 or 3 ring heteroatoms;P383145WO June 2025 10 a pyridine ring fused to a 5- or 6-membered ring containing 1, 2 or 3 ring heteroatoms; a pyrimidine ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; a pyrrole ring fused to a 5- or 6-membered ring containing 1, 2 or 3 ring heteroatoms; a pyrazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; a pyrazine ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; an imidazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; an oxazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; an isoxazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; a thiazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; an isothiazole ring fused to a 5- or 6-membered ring containing 1 or 2 ring heteroatoms; a thiophene ring fused to a 5- or 6-membered ring containing 1, 2 or 3 ring heteroatoms; a furan ring fused to a 5- or 6-membered ring containing 1, 2 or 3 ring heteroatoms; a cyclohexyl ring fused to a 5- or 6-membered heteroaromatic ring containing 1, 2 or 3 ring heteroatoms; and a cyclopentyl ring fused to a 5- or 6-membered heteroaromatic ring containing 1, 2 or 3 ring heteroatoms.

[0051] Particular examples of bicyclic heteroaryl groups containing a six membered ring fused to a five membered ring include but are not limited to benzfuranyl, benzthiophenyl, benzimidazolyl, benzoxazolyl, benzisoxazolyl, benzthiazolyl, benzisothiazolyl, isobenzofuranyl, indolyl, isoindolyl, indolizinyl, indolinyl, isoindolinyl, purinyl (e.g., adeninyl, guaninyl), indazolyl, benzodioxolyl and pyrazolopyridinyl groups.

[0052] Particular examples of bicyclic heteroaryl groups containing two fused six membered rings include but are not limited to quinolinyl, isoquinolinyl, chromanyl, thiochromanyl, chromenyl, isochromenyl, chromanyl, isochromanyl, benzodioxanyl, quinolizinyl, benzoxazinyl, benzodiazinyl, pyridopyridinyl, quinoxalinyl, quinazolinyl, cinnolinyl, phthalazinyl, naphthyridinyl and pteridinyl groups.

[0053] The term “aryl” means a cyclic or polycyclic aromatic ring having from 5 to 12 carbon atoms. The term aryl includes both monovalent species and divalent species. Examples of aryl groups include, but are not limited to, phenyl, biphenyl, naphthyl and the like. In particular embodiment, an aryl is phenyl.P383145WO June 2025 11

[0054] This specification also makes use of several composite terms to describe groups comprising more than one functionality. Such terms will be understood by a person skilled in the art. For example heterocyclyl(m-nC)alkyl comprises (m-nC)alkyl substituted by heterocyclyl.

[0055] The term “aryl(1-2C)alkyl” means an aryl group covalently attached to a (1-2C)alkylene group, both of which are defined herein. Examples of aryl-(1-2C)alkyl groups include benzyl, phenylethyl, and the like.

[0056] “Heteroaryl(1-3C)alkyl” means a heteroaryl group covalently attached to a (1- 3C)alkylene group, both of which are defined herein. Examples of heteroaryl-alkyl groups include pyridin-3-ylmethyl, 2-(benzofuran-2-yl)ethyl, and the like.

[0057] “Heterocyclyl(1-2C)alkyl” means a heterocyclyl group covalently attached to a (1- 2C)alkylene group, both of which are defined herein.

[0058] “(3-6C)cycloalkyl-(1-2C)alkyl” means a (3-6C)cycloalkyl group covalently attached to a (1-2C)alkylene group, both of which are defined herein.

[0059] The term "optionally substituted" refers to either groups, structures, or molecules that are substituted and those that are not substituted. The term “wherein a / any CH, CH2, CH3group or heteroatom (i.e. NH) within a R1group is optionally substituted” suitably means that (any) one of the hydrogen radicals of the R1group is substituted by a relevant stipulated group.

[0060] Where optional substituents are chosen from “one or more” groups it is to be understood that this definition includes all substituents being chosen from one of the specified groups or the substituents being chosen from two or more of the specified groups.

[0061] A wavy bond (is used herein to show a point of attachment.

[0062] The phrase “compound of the invention” means those compounds which are disclosed herein, both generically and specifically.

[0063] As used herein by itself or in conjunction with another term or terms, “pharmaceutically acceptable” refers to materials that are generally chemically and / or physically compatible with other ingredients (such as, for example, with reference to a formulation), and / or are generally physiologically compatible with the recipient (such as, for example, a subject) thereof.

[0064] As used herein by themselves or in conjunction with another term or terms, “subject(s)” and “patient(s)”, suitably refer to mammals, in particular humans.P383145WO June 2025 12 Compounds of the invention

[0065] In a first aspect, the present invention relates to a compound, or pharmaceutically acceptable salt thereof, having the structural formula I shown below:wherein: RS is (1-3C)alkyl; R1 is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a (1-6C)alkyl, -[CH2]m-(3- 6C)cycloalkyl, -[CH2]m-heterocyclyl group, -[CH2]m-aryl group or -[CH2]m-heteroaryl group, wherein integer m is 0, 1, 2 or 3; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; X is selected from N or CRx; wherein: Rxis selected from hydrogen, halo, (1-2C)alkyl, (1-2C)alkoxy or NH2; R2is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-4C)alkylene, (2-4C)alkenylene or (2-4C)alkynylene;P383145WO June 2025 13 X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -N(R100b)-C(O)-NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where each R100aand R100bgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n-(3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-aryl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; R3is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-4C)alkylene, (2-4C)alkenylene or (2-4C)alkynylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, -NR100c-, -N(R100d)-C(O)-NR100c-, -SO2N(R100c)- or -N(R100c)SO2-, where each R100cand R100dgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-heterocyclyl, -[CH2]p-aryl, or -[CH2]p-heteroaryl group, wherein integer p is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein:P383145WO June 2025 14 L4is absent or (1-4C)alkylene, (2-4C)alkenylene or (2-4C)alkynylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100e)-, -N(R100e)-C(O)-, -NR100e-, -N(R100f)-C(O)-NR100e-, -SO2N(R100e)- or -N(R100e)SO2-, where each R100eor R100fgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-heterocyclyl, -[CH2]q-aryl, or -[CH2]q-heteroaryl group, wherein integer q is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy.

[0066] Particular compounds of the invention include, for example, compounds of the formula I, or pharmaceutically acceptable salts, hydrates and / or solvates thereof, wherein, unless otherwise stated, each of RS, R1, R2, R3, R4and X have any of the meanings defined hereinbefore, or are as defined in any one of paragraphs (1) to (XX) hereinafter: (1) RS is (1-2C)alkyl; (2) RS is methyl; (3) R1 is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a (1-6C)alkyl, -[CH2]m-(3- 6C)cycloalkyl, -[CH2]m-[4 to 8 membered heterocyclyl], -[CH2]m-phenyl, or a -[CH2]m-[5- or 6-membered heteroaryl] group, wherein integer m is 0, 1, 2 or 3; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (4) R1 is selected from hydrogen, or a group: -Q whereinP383145WO June 2025 15 Q is selected from the group consisting of a (1-4C)alkyl, -[CH2]m-(3- 6C)cycloalkyl, -[CH2]m-[4 to 6 membered heterocyclyl], -[CH2]m-phenyl, or a -[CH2]m-[5- or 6-membered heteroaryl] group, wherein integer m is 0, 1, 2 or 3; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (5) R1is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a -[CH2]m-(3-6C)cycloalkyl or -[CH2]m-phenyl group, wherein integer m is 0, 1 or 2; and any cycloalkyl or phenyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1-2C)alkoxy, (1-2C)haloalkyl or (1- 2C)haloalkoxy; (6) R1is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a -[CH2]m-(3-6C)cycloalkyl or -[CH2]m-phenyl group, wherein integer m is 0, 1 or 2; and any cycloalkyl or phenyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, (1-2C)alkyl or (1-2C)alkoxy; (7) R1 is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a -[CH2]m-(3-4C)cycloalkyl or -[CH2]m-phenyl group, wherein integer m is 0 or 1; and any cycloalkyl or phenyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, (1-2C)alkyl or (1-2C)alkoxy; (8) R1 is selected from hydrogen, or a group:P383145WO June 2025 16 -Q wherein Q is -[CH2]m-(3-4C)cycloalkyl, wherein integer m is 0 or 1; and the cycloalkyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, (1- 2C)alkyl or (1-2C)alkoxy; (9) R1is selected from hydrogen, cyclopropyl or cyclobutyl; (10) R1is selected from hydrogen or cyclopropyl; (11) R1is hydrogen; (12) R1is cyclopropyl; (13) R2is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene, (2-3C)alkenylene or (2-3C)alkynylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -N(R100b)-C(O)-NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where each R100aand R100bgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-aryl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1-3C)alkoxy, (1- 3C)haloalkyl or (1-3C)haloalkoxy; (14) R2 is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where R100ais independently selected from hydrogen or (1-2C)alkyl; andP383145WO June 2025 17 Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-phenyl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; (15) R2is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where R100ais independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-phenyl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; (16) R2 is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where R100ais independently selected from hydrogen or (1-2C)alkyl; andP383145WO June 2025 18 Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-[4- to 8-membered heterocyclyl], -[CH2]n-phenyl, or -[CH2]n-[5- or 6-membered heteroaryl] group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (17) R2is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where R100ais independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-[4- to 8-membered heterocyclyl], -[CH2]n-phenyl, or -[CH2]n-[5- or 6-membered heteroaryl] group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (18) R2 is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)- N(R100a)-, -N(R100a)-C(O)-, -NR100a-, where R100ais independently selected from hydrogen or methyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-[4- to 8-membered heterocyclyl], -[CH2]n-phenyl, or -[CH2]n-[5- or 6-membered heteroaryl] group,P383145WO June 2025 19 wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (19) R2is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O- or -NR100a-, where R100ais independently selected from hydrogen or methyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl or (3- 6C)cycloalkyl group, wherein integer n is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1-2C)alkoxy; (20) R2is selected from:,P383145WO June 2025 20P383145WO June 2025 21(23) R3 is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-3C)alkylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, -NR100c-, -N(R100d)-C(O)-NR100c-, -SO2N(R100c)- or -N(R100c)SO2-, where each R100cand R100dgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-heterocyclyl, -[CH2]p-phenyl, or -[CH2]p-heteroaryl group, wherein integer p is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; (24) R3 is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-3C)alkylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, -NR100c-,P383145WO June 2025 22 -SO2N(R100c)- or -N(R100c)SO2-, where R100cis selected from hydrogen or (1- 2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-heterocyclyl, -[CH2]p-phenyl, or -[CH2]p-heteroaryl group, wherein integer p is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (25) R3is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-3C)alkylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -S(O)0-2-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, or -NR100c-, where R100cis selected from hydrogen or (1-2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-[4- to 8-membered heterocyclyl], -[CH2]p- phenyl, or -[CH2]p-[5- or 6-membered heteroaryl] group, wherein integer p is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (26) R3 is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-2C)alkylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, or -NR100c-, where R100cis selected from hydrogen or (1-2C)alkyl; andP383145WO June 2025 23 Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-[4- to 8-membered]heterocyclyl, -[CH2]p- phenyl, or -[CH2]p-[5- or 6-membered heteroaryl] group, wherein integer p is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (27) R3is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-2C)alkylene; X3is absent or is selected from the group consisting of -O- or -NR100c-, where R100cis selected from hydrogen or (1-2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-[4- to 6-membered]heterocyclyl, -[CH2]p- phenyl, or -[CH2]p-[5- or 6-membered heteroaryl] group, wherein integer p is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (28) R3 is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent; X3is absent; and Q3is selected from the group consisting of a (1-6C)alkyl, - [CH2]p-(3-6C)cycloalkyl, -[CH2]p-[4- to 6-membered]heterocyclyl, -[CH2]p- phenyl, or -[CH2]p-[5- or 6-membered heteroaryl] group, wherein integer p is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or moreP383145WO June 2025 24 substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (29) R3 is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent; X3is absent; and Q3is selected from the group consisting of a -[CH2]p-phenyl, or -[CH2]p-[5- or 6- membered heteroaryl] group, wherein integer p is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (30) R3is selected from hydrogen or phenyl optionally substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (31) R3is selected from hydrogen or phenyl optionally substituted (1-2C)alkyl; (32) R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-3C)alkylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100e)-, -N(R100e)-C(O)-, -NR100e-, -N(R100f)-C(O)-NR100e-, -SO2N(R100e)- or -N(R100e)SO2-, where each R100eor R100fgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-heterocyclyl, -[CH2]q-phenyl, or -[CH2]q-heteroaryl group, wherein integer q is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or moreP383145WO June 2025 25 substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy. (33) R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-3C)alkylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100e)-, -N(R100e)-C(O)-, -NR100e-, -SO2N(R100e)- or -N(R100e)SO2-, where R100eis selected from hydrogen or (1- 2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-heterocyclyl group, -[CH2]q-phenyl group, or -[CH2]q-heteroaryl group, wherein integer q is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (34) R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-3C)alkylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -S(O)0-2-, -C(O)-N(R100e)-, -N(R100e)-C(O)- or -NR100e-, where R100eis selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-[4- to 8-membered heterocyclyl], -[CH2]q- phenyl, or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (35) R4 is selected from hydrogen, halo, cyano or a group:P383145WO June 2025 26 -L4-X4-Q4wherein: L4is absent or (1-2C)alkylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)- N(R100e)-, -N(R100e)-C(O)-, or -NR100e-, where R100eis selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-[4- to 8-membered heterocyclyl], -[CH2]q- phenyl, or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (36) R4is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-2C)alkylene; X4is absent or is selected from the group consisting of -O- or -NR100e-, where R100eis selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-[4- to 6-membered heterocyclyl], -[CH2]q- phenyl, or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (37) R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-2C)alkylene; X4is absent; andP383145WO June 2025 27 Q4is selected from the group consisting of a (1-6C)alkyl, -[CH2]q-(3- 6C)cycloalkyl, -[CH2]q-[4- to 6-membered heterocyclyl], -[CH2]q-phenyl or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (38) R4is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-2C)alkylene; X4is absent; and Q4is selected from the group consisting of a (1-6C)alkyl, -[CH2]q-(3- 6C)cycloalkyl, -[CH2]q-[4- to 6-membered heterocyclyl], -[CH2]q-phenyl, or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (39) R4 is selected from hydrogen or a group: -L4-X4-Q4wherein: L4is absent or (1C)alkylene; X4is absent; and Q4is selected from the group consisting of a (1-6C)alkyl, (3-6C)cycloalkyl, 4- to 6-membered heterocyclyl, phenyl, or 5- or 6-membered heteroaryl group, wherein any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1-2C)alkoxy; (40) R4 is selected from hydrogen or a group: -L4-X4-Q4P383145WO June 2025 28 wherein: L4is absent or (1C)alkylene; X4is absent; and Q4is selected from the group consisting of a (1-6C)alkyl, (3-6C)cycloalkyl, 4- to 6-membered heterocyclyl, or phenyl, wherein any alkyl, cycloalkyl, phenyl, or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (41) R4is hydrogen; (42) X is selected from N or CH; (43) X is N; or (44) X is CH.

[0067] Suitably, in the compounds of formula I, RSis as defined in either paragraph (1) or paragraph (2) above. More suitably, RSIS as defined in paragraph (2) above.

[0068] Suitably, in the compounds of formula I, R1is as defined in any one of paragraphs (3) to (12) above. More suitably, R1is as defined in paragraph (4) above. Most suitably, R1is as defined in paragraph (10) above.

[0069] Suitably, in the compounds of formula I, R2 is as defined in any one of paragraphs (13) to (22) above. More suitably, R2 is as defined in paragraph (18) above. Most suitably, R2 is as defined in paragraph (22) above.

[0070] Suitably, in the compounds of formula I, R3 is as defined in any one of paragraphs (23) to (31) above. More suitably, R3 is as defined in paragraph (27) above. Most suitably, R3 is as defined in paragraph (30) or (31) above.

[0071] Suitably, in the compounds of formula I, R4 is as defined in any one of paragraphs (32) to (41) above. More suitably, R4 is as defined in paragraph (38) above. Most suitably, R4 is as defined in paragraph (41) above.

[0072] Suitably, in the compounds of formula I, X is as defined in any one of paragraphs (42) to (44) above. More suitably, X is as defined in paragraph (42) above.

[0073] In a particular group of compounds of formula I, the compounds, or a pharmaceutically acceptable salt thereof, have one of the structural formulae Ia to Io shown below:P383145WO June 2025 30wherein: RS, R1, R2, R3, R4 and X each have any of the meanings defined hereinbefore.

[0074] In an embodiment, when R1 is a substituent other than hydrogen, the compound is the (R) enantiomer. In a further embodiment, when R1 is a substituent other than hydrogen, the compound is the (S) enantiomer.

[0075] Suitably, the alkene group attached to the -S(O)2RSmoiety is in a trans or E configuration.

[0076] Suitably, in compounds of formula Ia to Ij, RSis methyl.

[0077] Suitably, in compounds of formula Ia to Ij, R1is as defined in any one of paragraphs (3) to (12) above. More suitably, R1is as defined in paragraph (4) above. Most suitably, R1is as defined in paragraph (10) above.

[0078] Suitably, in the compounds of formula Ia to Io, R2is as defined in any one of paragraphs (13) to (22) above. More suitably, R2is as defined in paragraph (18) above. Most suitably, R2is as defined in paragraph (22) above.P383145WO June 2025 31

[0079] Suitably, in the compounds of formula Ia to Ih or Ik to Io, R3is as defined in any one of paragraphs (23) to (31) above. More suitably, R3is as defined in paragraph (27) above. Most suitably, R3 is as defined in paragraph (30) or (31) above.

[0080] Suitably, in the compounds of formula Ia to If, Ii or Ij, R4is as defined in any one of paragraphs (32) to (41) above. More suitably, R4is as defined in paragraph (38) above. Most suitably, R4is as defined in paragraph (41) above.

[0081] Suitably, in the compounds of formula Ia, Ib, or Ig to Io, X is as defined in any one of paragraphs (42) to (44) above. More suitably, X is as defined in paragraph (42) above.

[0082] In a particular group of compounds of the invention, the compounds have the structural formula Ia shown above.

[0083] In a particular group of compounds of the invention, the compounds have the structural formula Ib shown above.

[0084] In a particular group of compounds of the invention, the compounds have the structural formula Ic shown above.

[0085] In a particular group of compounds of the invention, the compounds have the structural formula Id shown above.

[0086] In a particular group of compounds of the invention, the compounds have the structural formula Ie shown above.

[0087] In a particular group of compounds of the invention, the compounds have the structural formula If shown above.

[0088] In a particular group of compounds of the invention, the compounds have the structural formula Ig shown above.

[0089] In a particular group of compounds of the invention, the compounds have the structural formula Ih shown above.

[0090] In a particular group of compounds of the invention, the compounds have the structural formula Ii shown above.

[0091] In a particular group of compounds of the invention, the compounds have the structural formula Ij shown above.

[0092] In a particular group of compounds of the invention, the compounds have the structural formula Ik shown above.P383145WO June 2025 32

[0093] In a particular group of compounds of the invention, the compounds have the structural formula Im shown above.

[0094] In a particular group of compounds of the invention, the compounds have the structural formula In shown above.

[0095] In a particular group of compounds of the invention, the compounds have the structural formula Io shown above.

[0096] A particular group of compounds of the invention have any one of the formulae Ia to Io above, wherein, and where present: Rs is methyl; R1is as defined in paragraph (3) above; R2is as defined in paragraph (13) above; R3is as defined in paragraph (23) above; R4is as defined in paragraph (32) above; X in N or CH.

[0097] A further group of compounds of the invention have any one of the formulae Ia to Io above, wherein, and where present: Rs is methyl; R1 is as defined in paragraph (4) above; R2 is as defined in paragraph (15) above; R3 is as defined in paragraph (25) above; R4 is as defined in paragraph (34) above; X in N or CH.

[0098] A further group of compounds of the invention have any one of the formulae Ia to Io above, wherein, and where present: Rs is methyl; R1 is as defined in paragraph (4) above; R2 is as defined in paragraph (17) above; R3 is as defined in paragraph (27) above;P383145WO June 2025 33 R4is as defined in paragraph (36) above; X in N or CH.

[0099] A further group of compounds of the invention have any one of the formulae Ia to Io above, wherein, and where present: Rs is methyl; R1is as defined in paragraph (4) above; R2is as defined in paragraph (18) above; R3is as defined in paragraph (27) above; R4is as defined in paragraph (38) above; X in N or CH.

[0100] A further group of compounds of the invention have any one of the formulae Ia to Io above, wherein, and where present: Rs is methyl; R1is as defined in paragraph (10) above; R2is as defined in paragraph (22) above; R3is as defined in paragraph (30) above; R4is as defined in paragraph (41) above; X in N or CH.

[0101] A further group of compounds of the invention have any one of the formulae Ia to Io above, wherein, and where present: Rs is methyl; R1 is as defined in paragraph (10) above; R2 is as defined in paragraph (22) above; R3 is as defined in paragraph (31) above; R4 is as defined in paragraph (41) above; X in N or CH.P383145WO June 2025 34

[0102] Particular compounds of the present invention include any of the compounds described in the example section of the present application, or a pharmaceutically acceptable salt thereof, and, in particular, any of the following: 6-(cyclopentoxy)-3-methyl-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one; 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-3-tetrahydropyran-4-yl-2,7-naphthyridin-1-one; 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one; 3-benzyl-6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one; 2-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl-allyl]-6-(cyclopentoxy)-2,7- naphthyridin-1-one; 2-[(E,1S)-1-[(3-chloro-4-hydroxy-phenyl)methyl]-3-methylsulfonyl-allyl]-6-(cyclopentoxy)-2,7- naphthyridin-1-one; 6-(cyclopentoxy)-2-[(E,1S)-1-[(4-hydroxy-3-methyl-phenyl)methyl]-3-methylsulfonyl-allyl]-2,7- naphthyridin-1-one; 2-tert-butyl-6-[(E)-3-methylsulfonylallyl]pyrido[4,3-d]pyrimidin-5-one; 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1S,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one; 2‐(1,1‐difluoroethyl)‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one; 6‐[(1R,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐difluoroethyl)‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one; 6‐[(1S,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐difluoroethyl)‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐methylphenyl)pyrido[4,3‐ d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐ methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐one;P383145WO June 2025 35 2‐tert‐butyl‐6‐[(1S,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐ methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐one; or a pharmaceutically acceptable salt thereof.

[0103] Though the present invention may relate to any compound or particular group of compounds defined herein by way of optional, preferred or suitable features, or otherwise in terms of particular embodiments, the present invention may also relate to any compound or particular group of compounds that specifically excludes said optional, preferred or suitable features or particular embodiments.

[0104] Suitably, the present invention excludes any individual compounds not possessing the biological activity defined herein. Salts and Solvates

[0105] The compounds (including final products and intermediates) described herein may be isolated and used per se or may be isolated in the form of a salt, suitably pharmaceutically acceptable salts. It should be understood that the terms “salt(s)” and “salt form(s)” used by themselves or in conjunction with another term or terms encompasses all inorganic and organic salts, including industrially acceptable salts, as defined herein, and pharmaceutically acceptable salts, as defined herein, unless otherwise specified. As used herein, industrially acceptable salts are salts that are generally suitable for manufacturing and / or processing (including purification) as well as for shipping and storage, but may not be salts that are typically administered for clinical or therapeutic use. Industrially acceptable salts may be prepared on a laboratory scale, i.e. multi-gram or smaller, or on a larger scale, i.e. up to and including a kilogram or more.

[0106] Pharmaceutically acceptable salts, as used herein, are salts that are generally chemically and / or physically compatible with the other ingredients comprising a formulation, and / or are generally physiologically compatible with the recipient thereof. Pharmaceutically acceptable salts may be prepared on a laboratory scale, i.e. multi-gram or smaller, or on a larger scale, i.e. up to and including a kilogram or more. It should be understood that pharmaceutically acceptable salts are not limited to salts that are typically administered or approved by the FDA or equivalent foreign regulatory body for clinical or therapeutic use in humans. A practitioner of ordinary skill will readily appreciate that some salts are both industrially acceptable as well as pharmaceutically acceptable salts. It should be understood that all such salts, including mixed salt forms, are within the scope of the application.P383145WO June 2025 36

[0107] In one embodiment, the compounds of Formula I and sub-formulae thereof are isolated as pharmaceutically acceptable salts.

[0108] A suitable pharmaceutically acceptable salt of a compound of the invention is, for example, an acid addition salt of a compound of the invention which is sufficiently basic, for example, an acid-addition salt with, for example, an inorganic or organic acid, for example hydrochloric, hydrobromic, sulfuric, phosphoric, trifluoroacetic, formic, citric or maleic acid. -In addition a suitable pharmaceutically acceptable salt of a compound of the invention which is sufficiently acidic is an alkali metal salt, for example a sodium or potassium salt, an alkaline earth metal salt, for example a calcium or magnesium salt, an ammonium salt or a salt with an organic base which affords a physiologically acceptable- cation, for example a salt with methylamine, dimethylamine, trimethylamine, piperidine, morpholine or tris-(2-hydroxyethyl)amine.

[0109] In general, salts of the present application can be prepared in situ during the isolation and / or purification of a compound (including intermediates), or by separately reacting the compound (or intermediate) with a suitable organic or inorganic acid or base (as appropriate) and isolating the salt thus formed. The degree of ionisation in the salt may vary from completely ionised to almost non-ionised. In practice, the various salts may be precipitated (with or without the addition of one or more co-solvents and / or anti-solvents) and collected by filtration or the salts may be recovered by evaporation of solvent(s). Salts of the present application may also be formed via a “salt switch” or ion exchange / double displacement reaction, i.e. reaction in which one ion is replaced (wholly or in part) with another ion having the same charge. One skilled in the art will appreciate that the salts may be prepared and / or isolated using a single method or a combination of methods.

[0110] Representative salts include, but are not limited to, acetate, aspartate, benzoate, besylate, bicarbonate / carbonate, bisulphate / sulphate, borate, camsylate, citrate, edisylate, esylate, formate, fumarate, gluceptate, gluconate, glucuronate, hexafluorophosphate, hibenzate, hydrochloride / chloride, hydrobromide / bromide, hydroiodide / iodide, isethionate, lactate, malate, maleate, malonate, mesylate, methylsulphate, naphthylate, 2-napsylate, nicotinate, nitrate, orotate, oxalate, palmitate, pamoate, phosphate / hydrogen phosphate / dihydrogen phosphate, saccharate, stearate, succinate, tartrate, tosylate, trifluoroacetate and the like. Other examples of representative salts include alkali or alkaline earth metal cations such as, but not limited to, sodium, lithium, potassium, calcium, magnesium, and the like, as well as non-toxic ammonium, quaternary ammonium and amine cations including, but not limited to, ammonium, tetramethylammonium, tetraethylammonium, lysine,P383145WO June 2025 37 arginine, benzathine, choline, tromethamine, diolamine, glycine, meglumine, olamine and the like.

[0111] Certain compounds of the Formula I and sub-formulae thereof may exist in solvated as well as unsolvated forms such as, for example, hydrated forms. It is to be understood that the invention encompasses all such solvated forms that possess the biological activity described herein. Polymorphs

[0112] It is also to be understood that certain compounds of the Formula I and sub-formulae thereof may exhibit polymorphism, and that the invention encompasses all such forms that possess the biological activity described herein. N-oxides

[0113] Compounds of the Formula I and sub-formulae thereof containing an amine function may also form N-oxides. A reference herein to a compound of the Formula I and sub-formulae thereof that contains an amine function also includes the N-oxide. Where a compound contains several amine functions, one or more than one nitrogen atom may be oxidised to form an N-oxide. Particular examples of N-oxides are the N-oxides of a tertiary amine or a nitrogen atom of a nitrogen-containing heterocycle. N-Oxides can be formed by treatment of the corresponding amine with an oxidizing agent such as, but not limited to, hydrogen peroxide or a per-acid (e.g. a peroxycarboxylic acid), see for example Advanced Organic Chemistry, by Jerry March, 4thEdition, Wiley Interscience, pages. More particularly, N-oxides can be made by the procedure of L. W. Deady (Syn. Comm. 1977, 7, 509-514) in which the amine compound is reacted with m-chloroperoxybenzoic acid (mCPBA), for example, in an inert solvent such as, but not limited to, dichloromethane. Tautomers

[0114] Compounds of the Formula I and sub-formulae thereof may exist in a number of different tautomeric forms and references to compounds of the Formula I and sub-formulae thereof include all such forms. For the avoidance of doubt, where a compound can exist in one of several tautomeric forms, and only one is specifically described or shown, all others are nevertheless embraced by Formula I and sub-formulae thereof. Examples of tautomericP383145WO June 2025 38 forms include keto-, enol-, and enolate-forms, as in, for example, the following tautomeric pairs: keto / enol (illustrated below), pyrimidone / hydroxypyrimidine, imine / enamine, amide / imino alcohol, amidine / amidine, nitroso / oxime, thioketone / enethiol, and nitro / aci-nitro.keto enol enolateIsomers

[0115] Compounds that have the same molecular formula but differ in the nature or sequence of bonding of their atoms or the arrangement of their atoms in space are termed “isomers”. Isomers that differ in the arrangement of their atoms in space are termed “stereoisomers”. Stereoisomers that are not mirror images of one another are termed “diastereomers” and those that are nonsuperimposable mirror images of each other are termed “enantiomers”. When a compound has an asymmetric center, for example, it is bonded to four different groups, a pair of enantiomers is possible. An enantiomer can be characterized by the absolute configuration of its asymmetric center and is described by the R and S sequencing rules of Cahn and Prelog, or by the manner in which the molecule rotates the plane of polarized light and designated as dextrorotatory or levorotatory (i.e., as (+) or (- )isomers respectively). A chiral compound can exist as either individual enantiomer or as a mixture thereof. A mixture containing equal proportions of the enantiomers is called a “racemic mixture”.

[0116] Certain compounds of Formula I and sub-formulae thereof may have one or more asymmetric centres and therefore can exist in a number of stereoisomeric configurations. Consequently, such compounds can be synthesized and / or isolated as mixtures of enantiomers and / or as individual (pure) enantiomers, and, in the case of two or more asymmetric centres, single diastereomers and / or mixtures of diastereomers. It should be understood that the present application includes all such enantiomers and diastereomers and mixtures thereof in all ratios. Isotopes

[0117] The compounds of the present invention are described herein using structural formulas that do not specifically recite the mass numbers or the isotope ratios of the constituent atoms. As such it is intended that the present application includes compounds inP383145WO June 2025 39 which the constituent atoms are present in any ratio of isotope forms. For example, carbon atoms may be present in any ratio of12C,13C, and14C; hydrogen atoms may be present in any ratio of1H,2H, and3H; etc. Preferably, the constituent atoms in the compounds of the present invention are present in their naturally occurring ratios of isotope forms. Prodrugs and Metabolites

[0118] The compounds of Formula I and sub-formulae thereof may be administered in the form of a pro-drug which is broken down in the human or animal body to release a compound of the invention. A pro-drug may be used to alter the physical properties and / or the pharmacokinetic properties of a compound of the invention. A pro-drug can be formed when the compound of the invention contains a suitable group or substituent to which a property- modifying group can be attached. Examples of pro-drugs include in vivo cleavable ester derivatives that may be formed at a carboxy group or a hydroxy group in a compound of the Formula I and in-vivo cleavable amide derivatives that may be formed at a carboxy group or an amino group in a compound of the Formula I and sub-formulae thereof.

[0119] Accordingly, the present invention includes those compounds of the Formula I and sub-formulae thereof as defined hereinbefore when made available by organic synthesis and when made available within the human or animal body by way of cleavage of a pro-drug thereof. Accordingly, the present invention includes those compounds of the Formula I that are produced by organic synthetic means and also such compounds that are produced in the human or animal body by way of metabolism of a precursor compound, that is a compound of the Formula I and sub-formulae thereof may be a synthetically-produced compound or a metabolically-produced compound.

[0120] A suitable pharmaceutically acceptable pro-drug of a compound of the Formula I and sub-formulae thereof is one that is based on reasonable medical judgement as being suitable for administration to the human or animal body without undesirable pharmacological activities and without undue toxicity.

[0121] Various forms of pro-drug have been described, for example in the following documents :- a) Methods in Enzymology, Vol.42, p.309-396, edited by K. Widder, et al. (Academic Press, 1985); b) Design of Pro-drugs, edited by H. Bundgaard, (Elsevier, 1985);P383145WO June 2025 40 c) A Textbook of Drug Design and Development, edited by Krogsgaard-Larsen and H. Bundgaard, Chapter 5 “Design and Application of Pro-drugs”, by H. Bundgaard p.113-191 (1991); d) H. Bundgaard, Advanced Drug Delivery Reviews, 8, 1-38 (1992); e) H. Bundgaard, et al., Journal of Pharmaceutical Sciences, 77, 285 (1988); f) N. Kakeya, et al., Chem. Pharm. Bull., 32, 692 (1984); g) T. Higuchi and V. Stella, “Pro-Drugs as Novel Delivery Systems”, A.C.S. Symposium Series, Volume 14; and h) E. Roche (editor), “Bioreversible Carriers in Drug Design”, Pergamon Press, 1987.

[0122] A suitable pharmaceutically acceptable pro-drug of a compound of the Formula I and sub-formulae thereof that possesses a carboxy group is, for example, an in vivo cleavable ester thereof. An in vivo cleavable ester of a compound of the Formula I containing a carboxy group is, for example, a pharmaceutically acceptable ester which is cleaved in the human or animal body to produce the parent acid. Suitable pharmaceutically acceptable esters for carboxy include C1-6alkyl esters such as, but not limited to, methyl, ethyl and tert- butyl, C1-6alkoxymethyl esters such as, but not limited to, methoxymethyl esters, C1-6alkanoyloxymethyl esters such as, but not limited to, pivaloyloxymethyl esters, 3-phthalidyl esters, C3-8cycloalkylcarbonyloxy- C1-6alkyl esters such as, but not limited to, cyclopentylcarbonyloxymethyl and 1-cyclohexylcarbonyloxyethyl esters, 2-oxo-1,3- dioxolenylmethyl esters such as, but not limited to, 5-methyl-2-oxo-1,3-dioxolen-4-ylmethyl esters and C1-6alkoxycarbonyloxy- C1-6alkyl esters such as, but not limited to, methoxycarbonyloxymethyl and 1-methoxycarbonyloxyethyl esters.

[0123] A suitable pharmaceutically acceptable pro-drug of a compound of the Formula I and sub-formulae thereof that possesses a hydroxy group is, for example, an in vivo cleavable ester or ether thereof. An in vivo cleavable ester or ether of a compound of the Formula I and sub-formulae thereof containing a hydroxy group is, for example, a pharmaceutically acceptable ester or ether which is cleaved in the human or animal body to produce the parent hydroxy compound. Suitable pharmaceutically acceptable ester forming groups for a hydroxy group include inorganic esters such as, but not limited to, phosphate esters (including phosphoramidic cyclic esters). Further suitable pharmaceutically acceptable ester forming groups for a hydroxy group include C1-10alkanoyl groups such as, but not limited to, acetyl, benzoyl, phenylacetyl and substituted benzoyl and phenylacetyl groups, C1- 10alkoxycarbonyl groups such as, but not limited to, ethoxycarbonyl, N,N –(C1-6)2carbamoyl, 2-P383145WO June 2025 41 dialkylaminoacetyl and 2-carboxyacetyl groups. Examples of ring substituents on the phenylacetyl and benzoyl groups include aminomethyl, N-alkylaminomethyl, N,N- dialkylaminomethyl, morpholinomethyl, piperazin-1-ylmethyl and 4-(C1-4alkyl)piperazin-1- ylmethyl. Suitable pharmaceutically acceptable ether forming groups for a hydroxy group include ^-acyloxyalkyl groups such as, but not limited to, acetoxymethyl and pivaloyloxymethyl groups.

[0124] A suitable pharmaceutically acceptable pro-drug of a compound of the Formula I and sub-formulae thereof that possesses a carboxy group is, for example, an in vivo cleavable amide thereof, for example an amide formed with an amine such as, but not limited to, ammonia, a C1-4alkylamine such as, but not limited to, methylamine, a (C1-4alkyl)2amine such as, but not limited to, dimethylamine, N-ethyl-N-methylamine or diethylamine, a C1-4alkoxy- C2-4alkylamine such as, but not limited to, 2-methoxyethylamine, a phenyl-C1-4alkylamine such as, but not limited to, benzylamine and amino acids such as, but not limited to, glycine or an ester thereof.

[0125] A suitable pharmaceutically acceptable pro-drug of a compound of the Formula I and sub-formulae thereof that possesses an amino group is, for example, an in vivo cleavable amide derivative thereof. Suitable pharmaceutically acceptable amides from an amino group include, for example an amide formed with C1-10alkanoyl groups such as, but not limited to, an acetyl, benzoyl, phenylacetyl and substituted benzoyl and phenylacetyl groups. Examples of ring substituents on the phenylacetyl and benzoyl groups include aminomethyl, N- alkylaminomethyl, N,N-dialkylaminomethyl, morpholinomethyl, piperazin-1-ylmethyl and 4- (C1-4alkyl)piperazin-1-ylmethyl.

[0126] The in vivo effects of a compound of the Formula I and sub-formulae thereof may be exerted in part by one or more metabolites that are formed within the human or animal body after administration of a compound of the Formula I and sub-formulae thereof. As stated hereinbefore, the in vivo effects of a compound of the Formula I and sub-formulae thereof may also be exerted by way of metabolism of a precursor compound (a pro-drug). Pharmaceutical Compositions

[0127] According to a further aspect of the invention there is provided a pharmaceutical composition which comprises a compound of the invention as defined hereinbefore, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in association with a pharmaceutically acceptable diluent or carrier.P383145WO June 2025 42

[0128] The compositions of the invention may be in a form suitable for oral use (for example as tablets, lozenges, hard or soft capsules, aqueous or oily suspensions, emulsions, dispersible powders or granules, syrups or elixirs), for topical use (for example as creams, ointments, gels, or aqueous or oily solutions or suspensions), for administration by inhalation (for example as a finely divided powder or a liquid aerosol), for administration by insufflation (for example as a finely divided powder) or for parenteral administration (for example as a sterile aqueous or oily solution for intravenous, subcutaneous, intramuscular, intraperitoneal or intramuscular dosing or as a suppository for rectal dosing).

[0129] The compositions of the invention may be obtained by conventional procedures using conventional pharmaceutical excipients, well known in the art. Thus, compositions intended for oral use may contain, for example, one or more colouring, sweetening, flavouring and / or preservative agents.

[0130] An effective amount of a compound of the present invention for use in therapy is an amount sufficient to treat or prevent a proliferative condition referred to herein, slow its progression and / or reduce the symptoms associated with the condition.

[0131] The amount of active ingredient that is combined with one or more excipients to produce a single dosage form will necessarily vary depending upon the individual treated and the particular route of administration. For example, a formulation intended for oral administration to humans will generally contain, for example, from 0.5 mg to 1.5 g of active agent (more suitably from 0.5 to 600 mg, for example from 1 to 200 mg) compounded with an appropriate and convenient amount of excipients which may vary from about 5 to about 98 percent by weight of the total composition.

[0132] The size of the dose for therapeutic or prophylactic purposes of a compound of the Formula I will naturally vary according to the nature and severity of the conditions, the age and sex of the animal or patient and the route of administration, according to well-known principles of medicine.

[0133] It is to be noted that dosages and dosing regimens may vary with the type and severity of the condition to be alleviated, and may include the administration of single or multiple doses, i.e. QD (once daily), BID (twice daily), etc., over a particular period of time (days or hours). It is to be further understood that for any particular subject or patient, specific dosage regimens may need to be adjusted over time according to the individual need and the professional judgment of the person administering or supervising the administration of the pharmaceutical compositions. For example, doses may be adjusted based on pharmacokinetic or pharmacodynamic parameters, which may include clinical effects such asP383145WO June 2025 43 toxic effects and / or laboratory values. Thus, the present application encompasses intra- patient dose-escalation as determined by the person skilled in the art. Procedures and processes for determining the appropriate dosage(s) and dosing regimen(s) are well-known in the relevant art and would readily be ascertained by the skilled artisan. As such, one of ordinary skill would readily appreciate and recognize that the dosage ranges set forth herein are exemplary only and are not intended to limit the scope or practice of the pharmaceutical compositions described herein.

[0134] In using a compound of the invention for therapeutic or prophylactic purposes it will generally be administered so that a daily dose in the range, for example, 0.1 mg / kg to 75 mg / kg body weight is received, given if required in divided doses. In general lower doses will be administered when a parenteral route is employed. Thus, for example, for intravenous or intraperitoneal administration, a dose in the range, for example, 0.1 mg / kg to 30 mg / kg body weight will generally be used. Similarly, for administration by inhalation, a dose in the range, for example, 0.05 mg / kg to 25 mg / kg body weight will be used.

[0135] For the compounds of the present invention, oral administration is particularly suitable. The compounds of the present invention may be formulated as a tablet, capsule or solution for oral administration. Suitably, the compound of the present invention is formulated in a unit dosage form (e.g. a tablet or capsule) for oral administration. Typically, unit dosage forms will contain about 0.5 mg to 1.5 g of a compound of this invention. Synthesis

[0136] The compounds of the present invention can be prepared by any suitable technique known in the art. Particular methods for forming compounds of formula I defined herein are shown in the accompanying example section.

[0137] In the description of the synthetic methods described herein and in any referenced synthetic methods that are used to prepare the starting materials, it is to be understood that all proposed reaction conditions, including choice of solvent, reaction atmosphere, reaction temperature, duration of the experiment and workup procedures, can be selected by a person skilled in the art.

[0138] It is understood by one skilled in the art of organic synthesis that the functionality present on various portions of the molecule must be compatible with the reagents and reaction conditions utilised.P383145WO June 2025 44

[0139] It will be appreciated that during the synthesis of the compounds of the invention in the processes defined herein, or during the synthesis of certain starting materials, it may be desirable to protect certain substituent groups to prevent their undesired reaction. The skilled chemist will appreciate when such protection is required, and how such protecting groups may be put in place, and later removed.

[0140] For Examples of protecting groups see one of the many general texts on the subject, for example, ‘Protective Groups in Organic Synthesis’ by Theodora Green (publisher: John Wiley & Sons). Protecting groups may be removed by any convenient method described in the literature or known to the skilled chemist as appropriate for the removal of the protecting group in question, such methods being chosen so as to effect removal of the protecting group with the minimum disturbance of groups elsewhere in the molecule.

[0141] Thus, if reactants include, for example, groups such as amino, carboxy or hydroxy it may be desirable to protect the group in some of the reactions mentioned herein.

[0142] By way of example, a suitable protecting group for an amino or alkylamino group is, for example, an acyl group, for example an alkanoyl group such as, but not limited to, acetyl, an alkoxycarbonyl group, for example a methoxycarbonyl, ethoxycarbonyl or tbutoxycarbonyl group, an arylmethoxycarbonyl group, for example benzyloxycarbonyl, or an aroyl group, for example benzoyl. The deprotection conditions for the above protecting groups necessarily vary with the choice of protecting group. Thus, for example, an acyl group such as an alkanoyl or alkoxycarbonyl group or an aroyl group may be removed by, for example, hydrolysis with a suitable base such as, but not limited to, an alkali metal hydroxide, for example lithium or sodium hydroxide. Alternatively an acyl group such as a tertbutoxycarbonyl group may be removed, for example, by treatment with a suitable acid as hydrochloric, sulfuric or phosphoric acid or trifluoroacetic acid and an arylmethoxycarbonyl group such as a benzyloxycarbonyl group may be removed, for example, by hydrogenation over a catalyst such as palladium on carbon, or by treatment with a Lewis acid for example boron tris(trifluoroacetate). A suitable alternative protecting group for a primary amino group is, for example, a phthaloyl group which may be removed by treatment with an alkylamine, for example dimethylaminopropylamine, or with hydrazine.

[0143] A suitable protecting group for a hydroxy group is, for example, an acyl group, for example an alkanoyl group such as acetyl, an aroyl group, for example benzoyl, or an arylmethyl group, for example benzyl. The deprotection conditions for the above protecting groups will necessarily vary with the choice of protecting group. Thus, for example, an acyl group such as an alkanoyl or an aroyl group may be removed, for example, by hydrolysis withP383145WO June 2025 45 a suitable base such as an alkali metal hydroxide, for example lithium, sodium hydroxide or ammonia. Alternatively, an arylmethyl group such as a benzyl group may be removed, for example, by hydrogenation over a catalyst such as palladium on carbon.

[0144] A suitable protecting group for a carboxy group is, for example, an esterifying group, for example a methyl or an ethyl group which may be removed, for example, by hydrolysis with a base such as sodium hydroxide, or for example a t-butyl group which may be removed, for example, by treatment with an acid, for example an organic acid such as trifluoroacetic acid, or for example a benzyl group which may be removed, for example, by hydrogenation over a catalyst such as palladium on carbon.

[0145] Resins may also be used as a protecting group.

[0146] The methodology employed to synthesise a compound of formula (I) will vary depending on the nature of ring A, R1, R100, R2, R3, integer a, integer b, X4, X5, X6, X7, Rx4, Rx5, Rx6, Rx7,X8, R100aand R100band any substituent groups associated therewith. Suitable processes for their preparation are described further in the accompanying example section.

[0147] Once a compound of formula (I) has been synthesised by any one of the processes defined herein, the processes may then further comprise one or more of the additional steps of: (i) removing any residual protecting groups present; (ii) converting the compound formula (I) into another compound of formula (I); (iii) forming a pharmaceutically acceptable salt, hydrate or solvate of the compound of formula I; and / or (iv) forming a prodrug of the compound of formula I.

[0148] An example of (ii) above is when a compound of formula (I) is synthesised and then one or more of the groups of ring A, R1, R100, R2, R3, integer a, integer b, X4, X5, X6, X7, Rx4, Rx5, Rx6, Rx7, X8, R100a and R100b may be further reacted to change the nature of the group and provide an alternative compound of formula (I).

[0149] The resultant compounds of formula (I) can be isolated and purified using techniques well known in the art.P383145WO June 2025 46 Therapeutic Uses and Applications

[0150] The compounds of the present invention are inhibitors of WRN activity. Data showing the WRN inhibition for the exemplified compounds is presented in the accompanying example section.

[0151] Accordingly, the compounds of formula I are useful for the treatment and / or prevention of diseases and conditions in which WRN activity is implicated, such as, for example, but not limited to, the treatment and / or prevention of cancer and / or benign neoplasms.

[0152] In one aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in therapy.

[0153] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of a disease or condition in which WRN activity is implicated.

[0154] In another aspect, the present invention provides the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of a disease or condition in which WRN activity is implicated.

[0155] In another aspect, the present invention provides a method of treating a disease or condition in which WRN activity is implicated, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.

[0156] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of a disease or condition associated with aberrant activity of WRN.

[0157] In another aspect, the present invention provides the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of a disease or condition associated with aberrant activity of WRN.P383145WO June 2025 47

[0158] In another aspect, the present invention provides a method of treating a disease or condition associated with aberrant activity of WRN, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.

[0159] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of cancer or benign neoplasms.

[0160] In another aspect, the present invention provides the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of cancer or benign neoplasms.

[0161] In another aspect, the present invention provides a method of treating a cancer or a benign neoplasm, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.

[0162] A benign neoplasm may be, for example, hemangiomas, hepatocellular adenoma, cavernous haemangioma, focal nodular hyperplasia, acoustic neuromas, neurofibroma, bile duct adenoma, bile duct cystanoma, fibroma, lipomas, leiomyomas, mesotheliomas, teratomas, myxomas, nodular regenerative hyperplasia, trachomas, pyogenic granulomas, moles, uterine fibroids, thyroid adenomas, adrenocortical adenomas or pituitary adenomas. The benign neoplasm may be endometrial implants or a keratocystic odontogenic tumor.

[0163] In another aspect, the present invention provides a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein, for use in the treatment of a cancer.

[0164] In another aspect, the present invention the use of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in the manufacture of a medicament for use in the treatment of a cancer.

[0165] In another aspect, the present invention provides a method of treating cancer, said method comprising administering to a subject in need thereof an effective amount of a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein.P383145WO June 2025 48

[0166] In another aspect, the present invention provides a method for treating a cancer having microsatellite instability (MSI), the method comprises administering a compound of Formula I as defined herein, or a pharmaceutically acceptable salt, hydrate or solvate thereof, or a pharmaceutical composition as defined herein. In some embodiments, the cancer cells are characterized as having MSI low (MSI-L). In some embodiments, cancer cells characterized as having high MSI (MSI-H), used interchangeably with MSI-high. Cells can be characterized as MSI, including MSI-L or MSI-H, or as MSS (MS-stable), according to methods known in the art (see, for example, Dudley, Jonathan C., et al., Clinical Cancer Research, 22(4): 813-820, 2016.). MSI-H is used to classify tumors as having a high frequency of MSI. A tumor can be classified as MSI, including MSI-low or MSI-high, using polymerase chain reaction (PCR) and / or immunohistochemistry (IHC) assays. As stated in Dudley et al., a tumor is classified as MSI-H by PCR if (i) there is a shift (usually downward) in the size of at least two microsatellite loci from a reference panel of five microsatellite loci in tumor relative to normal, where the reference panel can be the “Bethesda Panel,” also referred to herein as the “NCI-Reference Panel (Bethesda, 1998)”, which includes two mononucleotide loci (BAT-25 and BAT-26) and three dinucleotide loci (D2S123, D5S346, and D17S250), or alternatively, the reference panel can be Promega Corporation’s MSI Analysis System, which includes five mononucleotide loci (BAT-25, BAT-26, NR-21, NR-24, and MONO-27); or (ii) there is a shift in the size of 30% or more microsatellite loci from a reference panel of more than five microsatellite loci in tumor relative to normal. The MSI-H phenotype is associated with germline defects in the mismatch repair genes MLH1, MSH2, MSH6, and PMS2, and is the primary phenotype observed in tumors from patients with HNPCC / Lynch syndrome. A tumor is classified as MSI-H in IHC test if it shows a loss of protein expression for at least 1 of the above 4 mismatch repair genes. Cells can be similarly classified as MSI-H using the tests described herein for tumors.

[0167] In some embodiments, a tumor or cell is classified as MSI-H using PCR to amplify the five microsatellite loci of the “Bethesda Panel” (BAT-25, BAT-26, D2S123, D5S346, and D17S250) from both tumor tissue or cells and normal tissue or cells, wherein the tumor or cell is classified as MSI-H if there is a shift in the size of at least two of the microsatellite loci from the tumor tissue or cells relative to the normal tissue or cells. In some embodiments, the shift in size of the microsatellite loci is a downward shift.

[0168] In some embodiments, a tumor or cell is classified as MSI-H using PCR to amplify the five microsatellite loci of Promega Corporation’s MSI Analysis System (BAT-25, BAT-26, NR- 21, NR-24, and MONO-27) from both tumor tissue or cells and normal tissue or cells, wherein the tumor or cell is classified as MSI-H if there is a shift in the size of at leastP383145WO June 2025 49 two of the microsatellite loci from the tumor tissue or cells relative to the normal tissue or cells. In some embodiments, the shift in size of the microsatellite loci is a downward shift.

[0169] In some embodiments, a tumor is classified as MSI-H using IHC to determine the expression level of the MMR proteins MLH1, MSH2, MSH6, and / or PMS2 in both tumor tissue and normal tissue, wherein the tumor is classified as MSI-H if there is a loss of protein expression for at least one of the MMR proteins in the tumor tissue relative to the normal tissue. In some embodiments, the loss of protein expression is a decrease of at least 20% (such as a decrease of 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 99%, or more).

[0170] In contrast, a tumor is classified as MSI-L by PCR if (i) there is a shift in the size of one microsatellite locus from a reference panel of five microsatellite loci in tumor relative to normal, where the reference panel can be the “Bethesda Panel” or Promega Corporation’s MSI Analysis System; or (ii) there is a shift in the size of less than 30% microsatellite loci from a reference panel of more than five microsatellite loci in tumor relative to normal. MSI- L tumors are thought to represent a distinct mutator phenotype with potentially different molecular etiology than MSI-H tumors (Thibodeau, 1998; Wu et al., 1999, Am J Hum Genetics 65: 1291-1298). Cells can be similarly classified as MSI-L using the tests described herein for tumors.

[0171] Cancers classified as MSI-H include, but not limited to, uterine corpus endometrial carcinoma, colon adenocarcinoma, stomach adenocarcinoma, rectal adenocarcinoma, adenoid cystic carcinoma, uterine carcinosarcoma, cervical squamous cell carcinoma, and endocervical adenocarcinoma.

[0172] In one embodiment, wherein the cancer is treatable by inhibition of WRN. In one embodiment, the cancer is characterized by MSI-H and / or dMMR.

[0173] The cancer may be non-metastatic or metastatic and which may be a solid tumour or a haematological (“liquid”) cancer. The cancer may, for example, be selected from: (1) Carcinoma, including for example tumours derived from stratified squamous epithelia (squamous cell carcinomas) and tumours arising within organs or glands (adenocarcinomas). Examples include breast, colon, lung, prostate, ovary, esophageal carcinoma (including, but not limited to, esophageal adenocarcinoma and squamous cell carcinoma), basal-like breast carcinoma, basal cell carcinoma (a form of skin cancer), squamous cell carcinoma (various tissues), head and neck carcinoma (including, but not limited to, squamous cell carcinomas), stomach carcinoma (including, but not limited to, stomach adenocarcinoma, gastrointestinal stromal tumor), signet ring cell carcinoma, bladder carcinoma (including transitional cell carcinoma (a malignant neoplasm of the bladder)), bronchogenic carcinoma, colorectal carcinoma (including, but not limited to, colon carcinoma and rectal carcinoma), analP383145WO June 2025 50 carcinoma, gastric carcinoma, lung carcinoma (including but not limited to small cell carcinoma (SCLC) and non-small cell carcinoma of the lung (NSCLC), lung adenocarcinoma, squamous cell carcinoma, large cell carcinoma, bronchioloalveolar carcinoma, and mesothelioma), neuroendocrine tumors (including but not limited to carcinoids of the gastrointestinal tract, breast, and other organs), adrenocortical carcinoma, thyroid carcinoma, pancreatic carcinoma (including, but not limited to, pancreatic ductal adenocarcinoma, pancreatic adenocarcinoma, acinar cell carcinoma, intraductal papillary mucinous neoplasm with invasive carcinoma, mucinous cystic neoplasm with invasive carcinoma, islet cell carcinoma and neuroendocrine tumors), breast carcinoma (including, but not limited to, ductal carcinoma, lobular carcinoma, inflammatory breast cancer, clear cell carcinoma, mucinous carcinoma), ovarian carcinoma (including, but not limited to, ovarian epithelial carcinoma or surface epithelial-stromal tumor including serous tumor, endometrioid tumor and mucinous cystadenocarcinoma, sex-cord- stromal tumor), liver and bile duct carcinoma (including, but not limited to, hepatocellular carcinoma, cholangiocarcinoma and hemangioma), prostate carcinoma, adenocarcinoma, brain tumours (including, but not limited to glioma, glioblastoma and medulloblastoma), germ cell tumors, sweat gland carcinoma, sebaceous gland carcinoma, papillary carcinoma, papillary adenocarcinoma, cystadenocarcinoma, kidney carcinoma (including, but not limited to, renal cell carcinoma, clear cell carcinoma and Wilm's tumor), medullary carcinoma, ductal carcinoma in situ or bile duct carcinoma, choriocarcinoma, seminoma, embryonal carcinoma, cervical carcinoma, uterine carcinoma (including, but not limited to, endometrial adenocarcinoma, uterine papillary serous carcinoma, uterine clear-cell carcinoma, uterine sarcomas and leiomyosarcomas, mixed mullerian tumors), testicular carcinoma, osteogenic carcinoma, epithelial carcinoma, sarcomatoid carcinoma, nasopharyngeal carcinoma, laryngeal carcinoma; oral and oropharyngeal squamous carcinoma; (2) Sarcomas, including: osteosarcoma and osteogenic sarcoma (bone); chondrosarcoma (cartilage); leiomyosarcoma (smooth muscle); rhabdomyosarcoma (skeletal muscle); mesothelial sarcoma and mesothelioma (membranous lining of body cavities); fibrosarcoma (fibrous tissue); angiosarcoma and hemangioendothelioma (blood vessels); liposarcoma (adipose tissue); glioma and astrocytoma (neurogenic connective tissue found in the brain); myxosarcoma (primitive embryonic connective tissue); chordoma, endotheliosarcoma, lymphangiosarcoma, lymphangioendotheliosarcoma, synovioma, Ewing's sarcoma, mesenchymous and mixed mesodermal tumor (mixed connective tissue types) and other soft tissue sarcomas; (3) Myeloma and multiple myeloma;P383145WO June 2025 51 (4) Hematopoietic tumours, including: myelogenous and granulocytic leukemia (malignancy of the myeloid and granulocytic white blood cell series); lymphatic, lymphocytic, and lymphoblastic leukemia (malignancy of the lymphoid and lymphocytic blood cell series); polycythemia vera and erythremia (malignancy of various blood cell products, but with red cells predominating); myelofibrosis. (5) Lymphomas, including: Hodgkin and Non-Hodgkin lymphomas; (6) Solid tumors of the nervous system including medulloblastoma, craniopharyngioma, ependymoma, pinealoma, hemangioblastoma, acoustic neuroma, oligodendroglioma, meningioma, neuroblastoma and schwannoma; (7) Melanoma, uveal melanoma and retinoblastoma; and (8) Mixed Types, including, e.g., adenosquamous carcinoma, mixed mesodermal tumor, carcinosarcoma or teratocarcinoma.

[0174] Further examples of cancers (and their benign counterparts) which may be treated (or inhibited) include, but are not limited to tumours of epithelial origin (adenomas and carcinomas of various types including adenocarcinomas, squamous carcinomas, transitional cell carcinomas and other carcinomas) such as carcinomas of the bladder and urinary tract, breast, gastrointestinal tract (including the esophagus, stomach (gastric), small intestine, colon, rectum and anus), liver (hepatocellular carcinoma), gall bladder and biliary system, exocrine pancreas, kidney, lung (for example adenocarcinomas, small cell lung carcinomas, non-small cell lung carcinomas, bronchioalveolar carcinomas and mesotheliomas), head and neck (for example cancers of the tongue, buccal cavity, larynx, pharynx, nasopharynx, tonsil, salivary glands, nasal cavity and paranasal sinuses), ovary, fallopian tubes, peritoneum, vagina, vulva, penis, cervix, myometrium, endometrium, thyroid (for example thyroid follicular carcinoma), adrenal, prostate, skin and adnexae (for example melanoma, basal cell carcinoma, squamous cell carcinoma, keratoacanthoma, dysplastic naevus); haematological malignancies (i.e. leukemias, lymphomas) and premalignant haematological disorders and disorders of borderline malignancy including haematological malignancies and related conditions of lymphoid lineage (for example acute lymphocytic leukemia [ALL], chronic lymphocytic leukemia [CLL], B-cell lymphomas such as diffuse large B-cell lymphoma [DLBCL], follicular lymphoma, Burkitt’s lymphoma, mantle cell lymphoma, MALT lymphoma, T-cell lymphomas and leukaemias, natural killer [NK] cell lymphomas, Hodgkin’s lymphomas, hairy cell leukaemia, monoclonal gammopathy of uncertain significance, plasmacytoma, multiple myeloma, and post-transplant lymphoproliferative disorders), and haematological malignancies and related conditions of myeloid lineage (forP383145WO June 2025 52 example acute myelogenous leukemia [AML], chronic myelogenous leukemia [CML], chronic myelomonocytic leukemia [CMML], hypereosinophilic syndrome, myeloproliferative disorders such as polycythaemia vera, essential thrombocythaemia and primary myelofibrosis, myeloproliferative syndrome, myelodysplastic syndrome, and promyelocytic leukemia); tumours of mesenchymal origin, for example sarcomas of soft tissue, bone or cartilage such as osteosarcomas, fibrosarcomas, chondrosarcomas, rhabdomyosarcomas, leiomyosarcomas, liposarcomas, angiosarcomas, Kaposi’s sarcoma, Ewing’s sarcoma, synovial sarcomas, epithelioid sarcomas, gastrointestinal stromal tumours, benign and malignant histiocytomas, and dermatofibrosarcoma protuberans; tumours of the central or peripheral nervous system (for example astrocytomas, gliomas and glioblastomas, meningiomas, ependymomas, pineal tumours and schwannomas); endocrine tumours (for example pituitary tumours, adrenal tumours, islet cell tumours, parathyroid tumours, carcinoid tumours and medullary carcinoma of the thyroid); ocular and adnexal tumours (for example retinoblastoma); germ cell and trophoblastic tumours (for example teratomas, seminomas, dysgerminomas, hydatidiform moles and choriocarcinomas); and paediatric and embryonal tumours (for example medulloblastoma, neuroblastoma, Wilms tumour, and primitive neuroectodermal tumours); or syndromes, congenital or otherwise, which leave the patient susceptible to malignancy (for example Xeroderma Pigmentosum).

[0175] Particular examples of cancers that can be targeted with the compounds of the present invention include, but are not limited to lymphoma, rhabdoid tumor, multiple myeloma, uterine cancer, gastric cancer, peripheral nervous system cancer, rhabdomyosarcoma, bone cancer, colorectal cancer, prostate cancer, mesothelioma, breast cancer, ovarian cancer, lung cancer, fibroblast cancer, central nervous system cancer, urinary tract cancer, upper aerodigestive cancer, leukemia, kidney cancer, skin cancer, esophageal cancer, and pancreatic cancer. More particularly, the cancers may be one or more of the following breast cancer, ovary cancer, pancreatic cancer, prostate cancer, lung cancer and / or colorectal cancer.

[0176] Many diseases are characterized by persistent and unregulated angiogenesis. Chronic proliferative diseases are often accompanied by profound angiogenesis, which can contribute to or maintain an inflammatory and / or proliferative state, or which leads to tissue destruction through the invasive proliferation of blood vessels. Tumour growth and metastasis have been found to be angiogenesis-dependent. Compounds of the invention may therefore be useful in preventing and disrupting initiation of tumour angiogenesis. In particular, the compounds of the invention may be useful in the treatment of metastasis and metastatic cancers.P383145WO June 2025 53

[0177] Metastasis or metastatic disease is the spread of a disease from one organ or part to another non-adjacent organ or part. The cancers which can be treated by the compounds of the invention include primary tumours (i.e. cancer cells at the originating site), local invasion (cancer cells which penetrate and infiltrate surrounding normal tissues in the local area), and metastatic (or secondary) tumours ie. tumours that have formed from malignant cells which have circulated through the bloodstream (haematogenous spread) or via lymphatics or across body cavities (trans-coelomic) to other sites and tissues in the body.

[0178] Particular cancers include hepatocellular carcinoma, melanoma, oesophageal, renal, colon, colorectal, lung e.g. mesothelioma or lung adenocarcinoma, breast, bladder, gastrointestinal, ovarian and prostate cancers.

[0179] The compounds may also be useful in the treatment of tumour growth, pathogenesis, resistance to chemo- and radio-therapy by sensitising cells to chemotherapy and as an anti-metastatic agent. Routes of Administration

[0180] The compounds of the invention or pharmaceutical compositions comprising these compounds may be administered to a subject by any convenient route of administration, whether systemically / peripherally or topically (i.e., at the site of desired action).

[0181] Routes of administration include, but are not limited to, oral (e.g. by ingestion); buccal; sublingual; transdermal (e.g. by a patch, plaster, etc.); transmucosal (e.g. by a patch, plaster, etc.); intranasal (e.g. by nasal spray); ocular (e.g. by eye drops, eye ointment etc.); pulmonary (e.g. by inhalation or insufflation therapy, for example via an aerosol, for example by the nose or mouth); rectal (e.g. by suppository or enema); vaginal (e.g. by pessary); parental, for example by injection, including subcutaneous, intradermal, intramuscular, intravenous, intraarterial, intracardiac, intrathecal, intraspinal, intracapsular, subcapsular, intraorbital, intraperitoneal, intratracheal, subcuticular, intraarticular, subarachnoid, and intrasternal; by implant of a depot or reservoir dosage form, for example subcutaneously or intramuscularly.

[0182] The compounds of the present invention are particularly suitable for oral administration.P383145WO June 2025 54 Combination Therapies

[0183] The compounds of the invention and salts, solvates thereof defined hereinbefore may be applied as a sole therapy or may involve, in addition to the compound of the invention, one or more additional therapeutic agents, e.g. an anti-tumour agent.

[0184] In the context of cancer treatment, in addition to the compound of the invention, therapy may additionally involve conventional surgery, radiotherapy and / or chemotherapy. Such chemotherapy may include one or more of the following categories of anti-tumour agents:- - other antiproliferative / antineoplastic drugs and combinations thereof, as used in medical oncology, such as, but not limited to, alkylating agents (for example cisplatin, oxaliplatin, carboplatin, cyclophosphamide, nitrogen mustard, melphalan, chlorambucil, busulphan, temozolamide and nitrosoureas); antimetabolites (for example gemcitabine and antifolates such as, but not limited to, fluoropyrimidines like 5-fluorouracil and tegafur, raltitrexed, methotrexate, cytosine arabinoside, and hydroxyurea); antitumour antibiotics (for example anthracyclines like adriamycin, bleomycin, doxorubicin, daunomycin, epirubicin, idarubicin, mitomycin-C, dactinomycin and mithramycin); antimitotic agents (for example vinca alkaloids like vincristine, vinblastine, vindesine and vinorelbine and taxoids like taxol and taxotere and polokinase inhibitors); and topoisomerase inhibitors (for example epipodophyllotoxins like etoposide and teniposide, amsacrine, irinotecan, topotecan and camptothecin); - cytostatic agents such as, but not limited to, antioestrogens (for example tamoxifen, fulvestrant, toremifene, raloxifene, droloxifene and iodoxyfene), antiandrogens (for example bicalutamide, flutamide, nilutamide and cyproterone acetate), LHRH antagonists or LHRH agonists (for example goserelin, leuprorelin and buserelin), progestogens (for example megestrol acetate), aromatase inhibitors (for example as anastrozole, letrozole, vorazole and exemestane) and inhibitors of 5^-reductase such as, but not limited to, finasteride; - anti-invasion agents [for example c-Src kinase family inhibitors like 4-(6-chloro-2,3- methylenedioxyanilino)-7-[2-(4-methylpiperazin-1-yl)ethoxy]-5-tetrahydropyran-4- yloxyquinazoline (AZD0530; International Patent Application WO 01 / 94341), N-(2-chloro-6- methylphenyl)-2-{6-[4-(2-hydroxyethyl)piperazin-1-yl]-2-methylpyrimidin-4-ylamino}thiazole- 5-carboxamide (dasatinib, BMS-354825; J. Med. Chem., 2004, 47, 6658-6661) and bosutinib (SKI-606), and metalloproteinase inhibitors like marimastat, inhibitors of urokinase plasminogen activator receptor function or antibodies to Heparanase];P383145WO June 2025 55 - inhibitors of growth factor function: for example such inhibitors include growth factor antibodies and growth factor receptor antibodies (for example the anti-erbB2 antibody trastuzumab [Herceptin™], the anti-EGFR antibody panitumumab, the anti-erbB1 antibody cetuximab [Erbitux, C225] and any growth factor or growth factor receptor antibodies disclosed by Stern et al. (Critical reviews in oncology / haematology, 2005, Vol. 54, pp11-29); such inhibitors also include tyrosine kinase inhibitors, for example inhibitors of the epidermal growth factor family (for example EGFR family tyrosine kinase inhibitors such as, but not limited to, N-(3-chloro-4-fluorophenyl)-7-methoxy-6-(3-morpholinopropoxy)quinazolin-4-amine (gefitinib, ZD1839), N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine (erlotinib, OSI-774) and 6-acrylamido-N-(3-chloro-4-fluorophenyl)-7-(3-morpholinopropoxy)-quinazolin- 4-amine (CI 1033), erbB2 tyrosine kinase inhibitors such as, but not limited to, lapatinib); inhibitors of the hepatocyte growth factor family; inhibitors of the insulin growth factor family; inhibitors of the platelet-derived growth factor family such as, but not limited to, imatinib and / or nilotinib (AMN107); inhibitors of serine / threonine kinases (for example Ras / Raf signalling inhibitors such as, but not limited to, farnesyl transferase inhibitors, for example sorafenib (BAY 43-9006), tipifarnib (R115777) and lonafarnib (SCH66336)), inhibitors of cell signalling through MEK and / or AKT kinases, c-kit inhibitors, abl kinase inhibitors, PI3 kinase inhibitors, Plt3 kinase inhibitors, CSF-1R kinase inhibitors, IGF receptor (insulin-like growth factor) kinase inhibitors; aurora kinase inhibitors (for example AZD1152, PH739358, VX-680, MLN8054, R763, MP235, MP529, VX-528 AND AX39459) and cyclin dependent kinase inhibitors such as, but not limited to, CDK2 and / or CDK4 inhibitors; - antiangiogenic agents such as, but not limited to, those which inhibit the effects of vascular endothelial growth factor, [for example the anti-vascular endothelial cell growth factor antibody bevacizumab (Avastin™) and for example, a VEGF receptor tyrosine kinase inhibitor such as, but not limited to, vandetanib (ZD6474), vatalanib (PTK787), sunitinib (SU11248), axitinib (AG-013736), pazopanib (GW 786034) and 4-(4-fluoro-2-methylindol-5-yloxy)-6- methoxy-7-(3-pyrrolidin-1-ylpropoxy)quinazoline (AZD2171; Example 240 within WO 00 / 47212), compounds such as, but not limited to, those disclosed in International Patent Applications WO97 / 22596, WO 97 / 30035, WO 97 / 32856 and WO 98 / 13354 and compounds that work by other mechanisms (for example linomide, inhibitors of integrin ^v^3 function and angiostatin)]; - vascular damaging agents such as, but not limited to, Combretastatin A4 and compounds disclosed in International Patent Applications WO 99 / 02166, WO 00 / 40529, WO 00 / 41669, WO 01 / 92224, WO 02 / 04434 and WO 02 / 08213;P383145WO June 2025 56 - an endothelin receptor antagonist, for example zibotentan (ZD4054) or atrasentan; - antisense therapies, for example those which are directed to the targets listed above, such as, but not limited to, ISIS 2503, an anti-ras antisense; - gene therapy approaches, including for example approaches to replace aberrant genes such as, but not limited to, aberrant p53 or aberrant BRCA1 or BRCA2, GDEPT (gene-directed enzyme pro-drug therapy) approaches such as, but not limited to, those using cytosine deaminase, thymidine kinase or a bacterial nitroreductase enzyme and approaches to increase patient tolerance to chemotherapy or radiotherapy such as multi-drug resistance gene therapy; and - immunotherapy approaches, including for example ex-vivo and in-vivo approaches to increase the immunogenicity of patient tumour cells, such as, but not limited to, transfection with cytokines such as interleukin 2, interleukin 4 or granulocyte-macrophage colony stimulating factor, approaches to decrease T-cell anergy, approaches using transfected immune cells such as, but not limited to, cytokine-transfected dendritic cells, approaches using cytokine-transfected tumour cell lines and approaches using anti-idiotypic antibodies.

[0185] In a particular embodiment, the antiproliferative treatment defined hereinbefore may involve, in addition to the compound of the invention, conventional surgery or radiotherapy or chemotherapy.

[0186] In a further embodiment, the antiproliferative treatment defined hereinbefore may involve, in addition to the compound of the invention, standard chemotherapy for the cancer concerned and / or therapy with DNA damage repair inhibitors (e.g. PARP, ATM, ATR, WEE1, CHK1, POLQ, USP1 and DNAPK inhibitors).

[0187] In a further embodiment, the antiproliferative treatment defined hereinbefore may involve, in addition to the compound of the invention, therapy with a PARP inhibitor.

[0188] Such conjoint treatment may be achieved by way of the simultaneous, sequential or separate dosing of the individual components of the treatment. Such combination products employ the compounds of this invention within the dosage range described hereinbefore and the other pharmaceutically-active agent within its approved dosage range.

[0189] According to this aspect of the invention there is provided a combination for use in the treatment of a cancer (for example a cancer involving a solid tumour) comprising a compound of the invention as defined hereinbefore, or a pharmaceutically acceptable salt, hydrate or solvate thereof, and another anti-tumour agent.P383145WO June 2025 57

[0190] According to this aspect of the invention there is provided a combination for use in the treatment of a proliferative condition, such as, but not limited to, cancer (for example a cancer involving a solid tumour), comprising a compound of the invention as defined hereinbefore, or a pharmaceutically acceptable salt, hydrate or solvate thereof, and any one of the anti-tumour agents listed herein above.

[0191] In a further aspect of the invention there is provided a compound of the invention or a pharmaceutically acceptable salt, hydrate or solvate thereof, for use in the treatment of cancer in combination with another anti-tumour agent, optionally selected from one listed herein above.

[0192] Herein, where the term “combination” is used it is to be understood that this refers to simultaneous, separate or sequential administration. In one aspect of the invention “combination” refers to simultaneous administration. In another aspect of the invention “combination” refers to separate administration. In a further aspect of the invention “combination” refers to sequential administration. Where the administration is sequential or separate, the delay in administering the second component should not be such as to lose the beneficial effect of the combination. In one embodiment, a combination refers to a combination product.

[0193] According to a further aspect of the invention there is provided a pharmaceutical composition which comprises a compound of the invention, or a pharmaceutically acceptable salt, hydrate or solvate thereof, in combination with an anti-tumour agent (optionally selected from one listed herein above), in association with a pharmaceutically acceptable diluent or carrier. Combination therapy with immune checkpoint inhibitors

[0194] Immune checkpoint proteins present on immune cells and / or cancer cells [e.g. CTLA4 (also known as cytotoxic T-lymphocyte-associated protein 4 and CD152), LAG3 (also known as lymphocyte-activation gene 3 and CD223), PD1 (also known as programmed cell death protein 1 and CD279), PD-L1 (also known as programmed death-ligand 1 and CD274), TIM- 3 (also known as T-cell immunoglobulin mucin-3) and TIGIT (also known as T-cell Immunoreceptor with Ig and ITIM domains) are molecular targets that have been found to play an important role in regulating anti-tumour immune responses. Inhibitors of these immune checkpoint proteins (e.g. CTLA4, LAG3, PD1, PD-L1, TIM-3 and / or TIGIT inhibitors) promoteP383145WO June 2025 58 an anti-tumour immune response that can be utilised to effectively treat certain forms of cancer.

[0195] In one aspect, the present invention relates to a combination comprising a compound as defined herein, or a pharmaceutically acceptable salt thereof, and an immune checkpoint inhibitor as defined herein, or a pharmaceutically acceptable salt thereof, for use in the treatment of a proliferative disorder.

[0196] In another aspect, the present invention relates to a use of a combination comprising a compound as defined herein, or a pharmaceutically acceptable salt thereof, and an immune checkpoint inhibitor as defined herein, or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for treating of a proliferative disorder.

[0197] In another aspect, the present invention relates to a method of treating of a proliferative disorder in a subject in need thereof comprising administering to said subject a combination comprising a compound as defined herein, or a pharmaceutically acceptable salt thereof, and an immune checkpoint inhibitor as defined herein, or a pharmaceutically acceptable salt thereof.

[0198] Suitably, the compound as defined herein, or a pharmaceutically acceptable salt thereof, is administered simultaneous, separate or sequential administeration with an immune checkpoint inhibitor, or a pharmaceutically acceptable salt thereof.

[0199] Any immune checkpoint inhibitor or immune stimulator may be used in the combination therapy defined herein.

[0200] In one embodiment, the immune stimulator is selected from a 4-1BB stimulator, a OX40 stimulator, a CD27 stimulator, a CD40 stimulator, and a DR3 stimulator. In another embodiment the immune checkpoint inhibitor is selected from a PD1-inhibitor, a PD-L1 inhibitor, a LAG3 inhibitor, CTLA-4 inhibitor, a TIM-3 inhibitor and / or a TIGIT inhibitor. In a particular embodiment, the immune checkpoint inhibitor is a PD1 or PD-L1 inhibitor.

[0201] PD-1 is a cell surface receptor protein present on immune cells such as T cells. PD- 1 plays an important role in down-regulating the immune system and promoting self-tolerance by suppressing T cell activation. The PD-1 protein is an immune checkpoint that guards against autoimmunity through a dual mechanism of promoting apoptosis (programmed cell death) in antigen specific T cells in lymph nodes, while simultaneously reducing apoptosis in regulatory T cells (anti-inflammatory suppressive T cells).

[0202] PD-1 therefore inhibits the immune system. This prevents autoimmune diseases, but it can also prevent the immune system from killing cancer cells.P383145WO June 2025 59

[0203] PD1 binds two ligands, PD-L1 and PD-L2. PD-L1 is of particular interest as it is highly expressed in several cancers and hence the role of PD1 in cancer immune evasion is well established. Monoclonal antibodies targeting PD-1 that boost the immune system are approved or are being developed for the treatment of cancer. Many tumour cells express PD- L1, an immunosuppressive PD-1 ligand; inhibition of the interaction between PD-1 and PD-L1 can enhance T-cell responses in vitro and mediate preclinical antitumour activity. This is known as immune checkpoint blockade.

[0204] Examples of drugs that target PD-1 include pembrolizumab (Keytruda) and nivolumab (Opdivo). These drugs have been shown to be effective in treating several types of cancer, including melanoma of the skin, non-small cell lung cancer, kidney cancer, bladder cancer, head and neck cancers, and Hodgkin lymphoma. They are also being studied for use against many other types of cancer. Examples of drugs in development include BMS-936559 (Bristol Myers Squibb), MGA012 (MacroGenics) and MEDI-0680 (MedImmune).

[0205] Examples of drugs that inhibit PD-L1 include atezolizumab (Tecentriq), avelumab (Bavencio) and durvalumab (Imfinzi). These drugs have also been shown to be helpful in treating different types of cancer, including bladder cancer, non-small cell lung cancer, and Merkel cell skin cancer (Merkel cell carcinoma). They are also being studied for use against other types of cancer.

[0206] Examples of LAG3 inhibitors include BMS-986016 / Relatlimab, TSR-033, REGN3767, MGD013 (bispecific DART binding PD-1 and LAG-3), GSK2831781 and LAG525.

[0207] Examples of CTLA-4 inhibitors include MDX-010 / ipilimumab, AGEN1884, and CP- 675,206 / Tremelimumab. Biological Activity

[0208] The biological assays described in the example section (Biological Assay 1 and 2) may be used to measure the pharmacological effects of the compounds of the present invention.

[0209] Although the pharmacological properties of the compounds of formula I vary with structural change, as expected, the compounds of the invention were found to be active in the assays described in Biological Assay 1. In general, the compounds of the invention demonstrate an IC50 of 100 μM or less in the assay described in Biological Assay 1, with preferred compounds of the invention demonstrating an IC50 of 50 μM or less and the most preferred compounds of the invention demonstrating an IC50 of 10 μM or less.P383145WO June 2025 60 EXAMPLES

[0210] The invention will now be illustrated, but not limited, by reference to the specific embodiments described in the following examples. Compounds are named using conventional IUPAC nomenclature, or as named by the chemical supplier.

[0211] The following synthetic procedures are provided for illustration of the methods used; for a given preparation or step the precursor used may not necessarily derive from the individual batch synthesized according to the step in the description given. Experimental and instrumentation

[0212] All solvents, chemical reagents and starting materials were obtained from commercial sources and were used without further purification or drying. NMR spectra were recorded using either a Bruker Avance III HD 500 MHz NMR spectrometer or a Bruker Avance III HD 400 MHz NMR spectrometer as indicated. Chemical shifts are quoted in ppm using residual undeuterated solvent as the internal reference.

[0213] LCMS spectra were recorded on a Waters AQUITYTM UPLCTM using either METHOD A; Waters UPLCTMBEHTMC18 column (2.1 mm × 50 mm, 1.7 µm; temperature: 40 °C), with an injection volume of 1 µL at a flow rate of 0.9 mL / min and a gradient of 5 – 100% B over 1.10 min, then 100% B for 0.25 min, where A = 0.1% formic acid in water, and B = 0.1% formic acid in acetonitrile, METHOD B; Phenomenex Kinetex-XB C18 column (2.1 mm × 100 mm, 1.7 µm; temperature: 40 °C), with an injection volume of 1 µL at a flow rate of 0.6 mL / min and a gradient of 5 – 100% B over 5.30 min, then 100% B for 0.50 min, where A = 0.1% formic acid in water, and B = 0.1% formic acid in acetonitrile, METHOD C; Phenomenex Kinetex® Evo C18 column (2.1 mm × 50 mm, 1.7 µm; temperature 40 °C), with an injection volume of 1 µL at a flow rate of 1.0 mL / min and a gradient of 1 – 100% B over 1.10 min, then 100% B for 0.25 min, where A = 0.2% ammonium hydroxide in water, and B = acetonitrile, or METHOD D; Phenomenex Kinetex® Evo C18 column (2.1 mm × 100 mm, 1.7 µm; temperature: 40 °C), with an injection volume of 1 μL and at a flow rate of 0.6 mL / min and a gradient of 5 – 100% B over 5.30 min, then 100% B for 0.50 min, where A = 0.2% ammonium hydroxide in water and B = acetonitrile, METHOD E; ACQUITY™ UPLCTMCSHTMC18 Column (2.1 mm × 50 mm, 1.7 µm; temperature 40 °C), with an injection volume of 1 µL at a flow rate of 0.9 mL / min and a gradient of 5 – 100% B over 1.10 min, then 100% B for 0.30 min, where A = 0.1% formic acid in water, and B = 0.1% formic acid in acetonitrile. Mass spectra were obtained using a Waters SQD, SQD2 or a QDA detector using electrospray ionisation inP383145WO June 2025 61 positive or negative mode. UV purity was assigned using AUC monitoring at 215, 254 or 280 nm. Data were integrated and reported using Waters MassLynx and OpenLynx software.

[0214] Preparative HPLC was performed using either METHOD 1; Waters SunfireTM C18 column (30 mm × 100 mm, 5 μm; temperature: room temperature), with an injection volume of 1500 μL at a flow rate of 40 mL / min at 30% B for 1.90 min then a gradient of 30 – 95% B over 9.60 min and held for 1.97 min, where A = 0.1% formic acid in water and B = 0.1% formic acid in acetonitrile, METHOD 2; Waters XBridgeTM C18 column (30 mm × 100 mm, 5 μm; temperature: room temperature), with an injection volume of 1500 μL at a flow rate of 40 mL / min at 30% B for 2.00 min then a gradient of 30 – 95% B over 9.50 min and held for 1.97 min, where A = 0.2% ammonium hydroxide in water and B = acetonitrile, METHOD 3; Waters SunfireTM C18 column (30 mm × 100 mm, 5 μm; temperature: room temperature), with an injection volume of 1500 μL at a flow rate of 40 mL / min at 10% B for 1.90 min then a gradient of 10 – 95% B over 14.10 min and held for 2.0 min, where A = 0.1% formic acid in water and B = 0.1% formic acid in acetonitrile, or METHOD 4; Waters XBridgeTM C18 column (30 mm × 100 mm, 5 μm; temperature: room temperature), with an injection volume of 1500 μL at a flow rate of 40 mL / min at 10% B for 2.00 min then a gradient of 10 – 95% B over 14.00 min and held for 2.00 min, where A = 0.2% ammonium hydroxide in water and B = acetonitrile. UV spectra were recorded at 215 nm using a Gilson detector.

[0215] Automated column chromatography was typically undertaken with a Biotage® Selekt automated purification system, employing pre-packed Sfär Silica D Duo 60 µm or Sfär Silica 60 µm cartridges of an appropriate size. Specific solvent gradients used are specified.

[0216] Unless otherwise specified, all lyophilisation was from MeCN / water mixtures. For Examples 10 to 15:

[0217] NMR spectra were recorded at 400 MHz using a BRUKER AVANCE NEO 400 MHz spectrometer.

[0218] LC-MS (Agilent-Acid): Agilent Technologies 1260 series, Binary Pump, Diode Array Detector. Nanochrom ChromCore C18, 3 μm, 4.6*50 mm. Mobile phase: A: 0.0375% TFA in water (v / v), B: 0.0187% TFA in MeCN (v / v). Flow Rate: 2.0 mL / min at 40°C. Detector: 214 nm, 254 nm, timetable:P383145WO June 2025 62

[0219] LC-MS (Agilent -Base): LC: Agilent Technologies 1260 series, Binary Pump, Diode Array Detector. YMC-Triart C185 μm 4.6*50 mm. Mobile phase: A:10 mM NH4HCO3, B: MeCN. Flow Rate: 2.0 mL / min at 40°C. Detector: 214 nm, 254 nm, timetable:HPLC (Waters-Acid):

[0220] LC: Waters Acquity UPLC, Binary Pump, Diode Array Detector. YMC Triart C183.0 μm, 2.1*100 mm column, column temperature: 40°C.

[0221] Acquisition wavelength: 214 nm, 254 nm; A: 10 mmol NH4HCO3 in water, B: MeCN.; Run time: 7.5 min; Post time: 2.0 min; Flow rate: 0.6 mL / min, timetable:

[0222] HPLC (Waters-Base): LC: Waters Acquity UPLC, Binary Pump, Diode Array Detector. YMC Triart C183.0 μm, 2.1*100mm column, column temperature: 40℃; Acquisition wavelength: 214 nm, 254 nm; A:P383145WO June 2025 63 10 mmol NH4HCO3 in water, B: MeCN.; Run time: 7.5 min; Post time: 2.0 min; Flow rate: 0.6 mL / min, timetable:

[0223] UPCC: Waters UPLC, Binary Pump, Diode Array Detector. Daicel IG-3, 3 μm 3.0*100 mm column, column temperature: 35℃; Acquisition wavelength: 254 nm; Flow rate: 1.0 mL / min; back pressure 2000 psi.

[0224] SFC: Waters SFC-150 Mgm, Daicel IG, 10 μm 30*250 mm column, column temperature: 35℃; Acquisition wavelength: 214 / 254 nm;; Flow rate: 45 mL / min; back pressure 100 bar. List of Abbreviations RT Room Temperature THF Tetrahydrofuran DCM Dichloromethane DIPEA N,N-diisopropylethylamine DMF Dimethylformamide Sat. Saturated TBME tert-butyl methyl ether T3P tripropyl-1,3,5,2λ⁵,4λ⁵,6λ⁵-trioxatriphosphinane-2,4,6-trione HPLC High-performance liquid chromatography rt Retention time LCMS Liquid chromatography mass spectrometry DMSO Dimethyl sulfoxide MW Microwave DIAD Diisopropyl azodicarboxylate DIBAL Diisobutylaluminum hydride eq molar equivalent BOC tert-butyloxycarbonyl TFA Trifluoracetic acid UPLC Ultra-performance liquid chromatography UPCC Ultra-performance chiral chromatography MeCN Acetonitrile SFC Supercritical fluid chromatography CDI 1,1'-CarbonyldiimidazoleP383145WO June 2025 64 Example 1 – Synthesis of 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7- naphthyridin-1-one tert-butyl N-(2-oxoethyl)carbamate

[0225] tert-butyl N-(2,3-dihydroxypropyl)carbamate (8.00 g, 41.8 mmol) was dissolved in water (80 mL), then the reaction vessel covered in foil to protect from light. sodium periodate (10.8 g, 50.5 mmol) was added and the mixture allowed to stir for 15 min. The reaction mixture was then filtered and the filtrate was extracted using chloroform (4 x 50 mL). The combined organic layers were dried over MgSO4, filtered and concentrated under reduced pressure to afford tert-butyl N-(2-oxoethyl)carbamate (4.80 g, 61% yield) as a colourless oil that was used without any further purification in the next step.1H NMR (400 MHz, CDCl3) δ 9.65 (s, 1H), 5.19 (s, 1H), 4.07 (d, J = 4.9 Hz, 2H), 1.45 (s, 9H). tert-butyl N-[(E)-3-methylsulfonylallyl]carbamate

[0226] 1-[ethoxy(methylsulfonylmethyl)phosphoryl]oxyethane (2.75 g, 12.0 mmol) was dissolved in anhydrous THF (70 mL) at 0 °C.60% sodium hydride in mineral oil (502 mg, 12.5 mmol) was added, then the mixture stirred for 15 mins. tert-butyl N-(2- oxoethyl)carbamate (2.72 g, 11.96 mmol) was added as a solution in anhydrous THF (20 mL) and the reaction allowed to warm to rt over 1 h. The mixture was partitioned between EtOAc (25 mL) and 1 M HCl(aq)(to give aq pH ~7). The aqueous was extracted with EtOAc (25 mL x 2), then the combined organics dried over Na2SO4, filtered and the solvent removed under reduced pressure. The residue was purified using automated column chromatography (0-20% ethyl acetate in DCM) to afford tert-butyl N-[(E)-3-methylsulfonylallyl]carbamate (1.32 g, 45% Yield).1H NMR (400 MHz, CDCl3) δ 6.92 (dt, J = 15.1, 4.3 Hz, 1H), 6.50 (dt, J = 15.2, 2.0 Hz, 1H), 4.79 (s, 1H), 4.00 (s, 2H), 2.94 (s, 3H), 1.46 (s, 9H).P383145WO June 2025 65 [(E)-3-methylsulfonylallyl]ammonium chloride

[0227] tert-Butyl N-[(E)-3-methylsulfonylallyl]carbamate (1.32 g, 5.33 mmol) was dissolved in DCM (5 mL), then trifluoroacetic acid (5 mL, 65.3 mmol) added and the mixture stirred at room temperature. After 1 h toluene (1 mL) was added, and the solvent was removed under reduced pressure. The residue dissolved in methanol (3 mL and added to a stirring mixture of diethyl ether (75 mL) and 4 M hydrogen chloride in dioxane (12 mL, 48.0 mmol) at 0 °C. The solids were filtered and dried under vacuum to afford [(E)-3- methylsulfonylallyl]ammonium;chloride (779 mg, 85% Yield) as a pale brown solid.1H NMR (400 MHz, DMSO-d6) δ 8.36 (s, 3H), 7.01 (dt, J = 15.4, 1.7 Hz, 1H), 6.75 (dt, J = 15.4, 5.6 Hz, 1H), 3.72 (s, 2H), 3.05 (s, 3H). 6-(cyclopentoxy)-4-methyl-pyridine-3-carbonitrile

[0228] 60% sodium hydride in mineral oil (5.24 g, 0.131 mol) in 4 portions was added to a solution of cyclopentanol (11.9 mL, 0.131 mol) in anhydrous THF (100 mL) under a nitrogen atmosphere at 0 ºC. The reaction mixture was stirred for 15 min then 6-chloro-4- methylpyridine-3-carbonitrile (10.0 g, 65.5 mmol) was added. The mixture was stirred at 0 °C for 1 h, then at room temperature overnight. The mixture was quenched with 2 M HCl(aq) and extracted with ethyl acetate (2 x 50 mL). The organic extracts were combined, dried over sodium sulphate and concentrated under reduced pressure. The residue was purified by automated column chromatography (5-15% ethyl acetate in heptane) to afford 6- (cyclopentoxy)-4-methyl-pyridine-3-carbonitrile (12.5 g, 92% yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 8.57 (s, 1H), 6.85 (s, 1H), 5.45 – 5.35 (m, 1H), 2.42 – 2.37 (m, 3H), 2.00 – 1.87 (m, 2H), 1.78 – 1.64 (m, 4H), 1.64 – 1.53 (m, 2H). LCMS: Method A (ESI+), rt (min): 1.09, [M+H]+ m / z: 203.2, Purity: 96%P383145WO June 2025 66 6-(cyclopentoxy)-4-methyl-pyridine-3-carboxylic acid

[0229] 6-(cyclopentoxy)-4-methyl-pyridine-3-carbonitrile (12.5 g, 60.5 mmol) was dissolved in ethanol (60 mL) and 5 M NaOH(aq) (36 mL, 0.180 mol) was added. The suspension was stirred at 100 °C overnight. The reaction mixture was retreated with 5 M NaOH(aq)(6 mL, 30 mmol) and stirred at 100 °C for another 4 h. The mixture was concentrated under reduced pressure, then quenched with 2 M HCl(aq)to ~pH 2. The resulting suspension was filtered, washing with small amounts of water and ethyl acetate, before being dried in a vacuum oven to give 6-(cyclopentoxy)-4-methyl-pyridine-3-carboxylic acid (11.7 g, 83% yield) as an off- white powder.1H NMR (400 MHz, DMSO-d6) δ 12.80 (s, 1H), 8.62 (s, 1H), 6.68 (s, 1H), 5.47 – 5.35 (m, 1H), 2.48 (s, 3H), 2.02 – 1.83 (m, 2H), 1.75 – 1.63 (m, 4H), 1.63 – 1.51 (m, 2H). LCMS: Method B (ESI+), rt (min): 3.01, [M+H]+ m / z: 222.1, Purity: 91% 6-(cyclopentoxy)-4-(2-oxoethyl)pyridine-3-carboxylic acid

[0230] Diisopropylamine (0.697 mL, 4.97 mmol) was dissolved in THF (5 mL) and cooled to -20 °C.2.5 M n-butyllithium in hexanes (1.90 mL, 4.75 mmol) was added and the mixture stirred at -20 °C for 15 mins, then cooled to -78 °C. A solution of 6-(cyclopentoxy)-4- methyl-pyridine-3-carboxylic acid (0.500 g, 2.26 mmol) in THF (5 mL) was then added. The mixture was stirred at -78 °C for 30 mins, then at -20 °C for 15 mins. The mixture was cooled back to -78 °C, then N,N-dimethylformamide (0.53 mL, 6.78 mmol) was added. The mixture was stirred at -78 °C for 45 mins, then at room temperature for 1 h. The mixture was quenched with 1 M HCl(aq) (adjusted to ~pH 1) and extracted with ethyl acetate (1 x 10 mL). The aqueous was adjusted to ~pH 3 using sat. NaHCO3(aq) and extracted with ethyl acetate (2 x 10 mL). The organic extracts were combined, dried over anhydrous sodium sulphate and concentrated under reduced pressure. The residue was then purified by automated column chromatography (0-80% EtOAc in heptane) to afford 6-(cyclopentoxy)-4-(2-oxoethyl)pyridine-3-carboxylic acidP383145WO June 2025 67 (327 mg, 46% yield) as an off-white solid. LCMS: Method A (ESI+), rt (min): 0.80, [M+H]+ m / z: 250.1, Purity: 96% Example 1 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one

[0231] 50% T3P in ethyl acetate (367 µL, 0.623 mmol) was added to a mixture of 6- (cyclopentoxy)-4-(2-oxoethyl)pyridine-3-carboxylic acid (70 mg, 0.208 mmol), [(E)-3- methylsulfonylallyl]ammonium chloride (54 mg, 0.312 mmol), DIPEA (145 µL, 0.831 mmol) in DMF (1.5 mL) and the reaction was stirred for 40 mins at RT. The mixture was diluted with water (5 mL) and extracted with ethyl acetate (2 x 15 mL). The organics were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using prep HPLC (Method 3, 254 nm) followed by lyophilisation to afford 6- (cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one (22 mg, 29% Yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 9.06 – 9.02 (m, 1H), 7.54 – 7.47 (m, 1H), 6.91 – 6.82 (m, 2H), 6.65 – 6.57 (m, 1H), 6.56 – 6.52 (m, 1H), 5.48 – 5.41 (m, 1H), 4.82 – 4.74 (m, 2H), 2.98 (s, 3H), 2.04 – 1.91 (m, 2H), 1.79 – 1.67 (m, 4H), 1.67 – 1.56 (m, 2H). LCMS: Method B (ESI+), rt (min): 2.68, [M+H]+ m / z: 349.4, Purity: 100%. Example 2 – Synthesis of 2-tert-butyl-6-[(E)-3-methylsulfonylallyl]pyrido[4,3- d]pyrimidin-5-one methyl 2-(dimethylaminomethylene)-3-oxo-butanoate

[0232] methyl 3-oxobutanoate (0.93 mL, 8.62 mmol) was stirred at RT and N,N- dimethylformamide dimethyl acetal (1.45 mL, 10.9 mmol) was added dropwise and left to stir overnight. The reaction mixture was then concentrated under reduced pressure and azeotropically dried then placed under high vacuum to afford methyl 2- (dimethylaminomethylene)-3-oxo-butanoate (1.48 g, 98% yield) as a dark orange oil.1H NMR (400 MHz, DMSO-d6) δ 7.63 (s, 1H), 3.63 (s, 3H), 3.28 – 2.80 (m, 6H), 2.13 (s, 3H).P383145WO June 2025 68 2-tert-butyl-4-methyl-pyrimidine-5-carboxylic acid

[0233] To a stirred ice-cold solution of 2,2-dimethylpropanimidamide hydrochloride (1:1) (1.18 g, 8.64 mmol) in anhydrous methanol (10 mL) was added sodium methoxide (30 wt% in methanol) (4.92 mL, 25.8 mmol). A solution of methyl 2-(dimethylaminomethylene)-3- oxo-butanoate (1.48 g, 8.62 mmol) in anhydrous methanol (4.0 mL) was added over 5 mins and then mixture heated to 70 °C for 1.5 hrs. The reaction mixture was cooled and diluted with water (2 mL). The organics were removed under reduced pressure and the aqueous mixture was extracted with ethyl acetate (2 x 10 mL). The aqueous solution was then acidified to pH 1 with 1 M HCl(aq)and extracted with ethyl acetate (2 x 20 mL). The organic extracts were dried with brine and MgSO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (0-80% TBME in heptane) to afford 2-tert- butyl-4-methyl-pyrimidine-5-carboxylic acid (890 mg, 4.44 mmol, 52% yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 13.45 (s, 1H), 9.02 (s, 1H), 2.71 (s, 3H), 1.35 (s, 9H). LCMS: Method A (ESI+), rt (min): 0.83, [M+H]+ m / z: 195.1, Purity: 97%. 2-tert-butyl-4-(2-oxoethyl)pyrimidine-5-carboxylic acid

[0234] Diisopropylamine (0.30 mL, 2.14 mmol) was dissolved in THF (5 mL) and cooled to - 30 °C.2 M n-butyllithium in cyclohexane (1.10 mL, 2.20 mmol) was added and the mixture stirred at -30 °C for 15 mins, then cooled to -78 °C. A solution of 2-tert-butyl-4-methyl- pyrimidine-5-carboxylic acid (200 mg, 1.03 mmol) in THF (5 mL) was then added. The mixture was stirred at -78 °C for 30 mins, then at -20 °C for 15 mins. The mixture was cooled back to -78 °C, then DMF (0.24 mL, 3.10 mmol) was added. The mixture was stirred at -78 °C for 45 mins, then at room temperature for 1 h. The reaction mixture was quenched with 1 M HCl(aq)P383145WO June 2025 69 until pH ~1 and extracted with ethyl acetate (3 x 10 mL). The organics were combined, washed with brine (20 mL), dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified automated column chromatography (0-100% TBME in heptane) to afford 2-tert-butyl-4-(2-oxoethyl)pyrimidine-5-carboxylic acid (32.0 mg, 11% yield) as a yellow solid.1H NMR (400 MHz, DMSO-d6) δ 13.52 – 13.37 (m, 1H), 9.11 (s, 1H), 8.99 (s, 1H), 3.52 – 3.41 (m, 1H), 3.11 – 2.98 (m, 1H), 1.37 – 1.31 (m, 9H). LCMS: Method A (ESI+), rt (min): 0.75, [M+H]+ m / z: 223.1, Purity: 93%. Example 2 2-tert-butyl-6-[(E)-3-methylsulfonylallyl]pyrido[4,3-d]pyrimidin-5-one

[0235] tert-butyl N-[(E)-3-methylsulfonylallyl]carbamate (33 mg, 0.140 mmol) was dissolved in 4 M HCl in dioxane (0.40 mL, 1.60 mmol) and stirred at rt for 30 min before being concentrated under reduced pressure. To the residue was then added 2-tert-butyl-4-(2- oxoethyl)pyrimidine-5-carboxylic acid (30 mg, 0.135 mmol) and DMF (0.8 mL) and stirred for 1 min. DIPEA (0.09 mL, 0.517 mmol) was added and the mixture stirred for a further minute. Finally, 50% T3P in ethyl acetate (0.24 mL, 0.403 mmol) was added and the mixture allowed to stir for 5 min at rt. The reaction mixture was concentrated using high vacuum before being dissolved in water and extracted with ethyl acetate (3 x 10 mL). Organic extracts washed with brine, dried over MgSO4and concentrated under reduced pressure. The residue was purified using prep HPLC (Method 1, 215 nm) to afford 2-tert-butyl-6-[(E)-3- methylsulfonylallyl]pyrido[4,3-d]pyrimidin-5-one (7.2 mg, 17% yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 9.46 (s, 1H), 7.92 (d, J = 7.6 Hz, 1H), 6.89 (dt, J = 15.4, 4.2 Hz, 1H), 6.70 (d, J = 7.6 Hz, 1H), 6.68 – 6.62 (m, 1H), 4.88 – 4.83 (m, 2H), 2.97 (s, 3H), 1.42 (s, 9H). LCMS: Method B (ESI+), rt (min): 2.50, [M+H]+ m / z: 322.2, Purity: 100%.P383145WO June 2025 70 Example 3 - Synthesis of 6-(cyclopentoxy)-2-[(E,1S)-1-cyclopropyl-3-methylsulfonyl- allyl]-2,7-naphthyridin-1-one tert-butyl N-[(1S)-1-cyclopropyl-2-[methoxy(methyl)amino]-2-oxo-ethyl]carbamate

[0236] DIPEA (2.50 mL, 14.3 mmol) and N-methoxymethanamine hydrochloride (687 mg, 7.04 mmol) were suspended in DCM (10 mL). After being put under nitrogen, DIPEA (2.50 mL, 14.3 mmol) and 50 % T3P in ethyl acetate (3.00 mL, 5.04 mmol) were added and the reaction mixture was left to stir at room temperature for 2 h 10 min. Sat. NaHCO3 (aq)(20 mL) was added and the layers separated and further extracted with DCM (2 x 20 mL). The combined organics were dried over Na2SO4, filtered and concentrated under reduced pressure to afford tert-butyl N-[(1S)-1-cyclopropyl-2-[methoxy(methyl)amino]-2-oxo-ethyl]carbamate (1.16 g, 89% yield) as a colourless oil that solidified into an off white solid when left overnight.1H NMR (400 MHz, DMSO-d6) δ 7.08 (d, J = 8.0 Hz, 1H), 4.08 – 3.95 (m, 1H), 3.72 – 3.68 (m, 3H), 3.11 (s, 3H), 1.36 (s, 9H), 1.10 – 0.95 (m, 1H), 0.47 – 0.34 (m, 2H), 0.33 – 0.23 (m, 2H). LCMS: Method A (ESI+), rt (min): 0.79, [M+H]+ m / z: 259.2, Purity: 100%. tert-butyl N-[(E,1S)-1-cyclopropyl-3-methylsulfonyl-allyl]carbamate

[0237] tert-butyl N-[(1S)-1-cyclopropyl-2-[methoxy(methyl)amino]-2-oxo- ethyl]carbamate (1.13 g, 4.37 mmol) was dissolved in anhydrous THF (12 mL), put under a nitrogen atmosphere, and cooled to 0 °C.2.4 M Lithium aluminiuim hydride in THF (3.60 mL, 8.64 mmol) was added slowly, and the mixture was stirred at 0 °C for 45 mins. Solid sodium sulfate decahydrate was added in small increments, this caused vigorous bubbling and small additions were continued until bubbling stopped. The mixture was diluted with ethyl acetate (20 mL) and vacuum filtered, rinsing the filter cake with ethyl acetate (20 mL). The filtrate was washed with saturated NaHCO3 (aq)(20 mL) and brine (20 mL), dried over Na2SO4, filtered and concentrated under reduced pressure to afford the desired aldehyde diethylP383145WO June 2025 71 [(methylsulfonyl)methyl]phosphonate (1.31 g, 5.68 mmol) was dissolved in anhydrous THF (12 mL) and cooled to 0 °C under a nitrogen atmosphere. 3 M Methyl magnesium bromidediethyl ether (1.90 mL, 5.70 mmol) was added, and the mixture was stirred at 0 °C for 20 min. Next, a solution of the previously isolated aldehyde in anhydrous THF (10 mL) was slowly added, and the mixture allowed to warm to RT over 2 h. The reaction mixture was quenched with 1 M HCl(aq)and then brought to ~ pH 8 with sat. NaHCO3(aq)solution. The mixture extracted with ethyl acetate (3 x 30 mL). The organic extracts were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (0-100 % TBME in heptane increasing to 25 % methanol in ethyl acetate) to afford tert-butyl N-[(E,1S)-1-cyclopropyl-3-methylsulfonyl- allyl]carbamate (412 mg, 34% yield) as a colourless oil that solidified after standing at RT.1H NMR (400 MHz, DMSO-d6) δ 7.26 (d, J = 8.7 Hz, 1H), 6.73 – 6.68 (m, 2H), 3.69 – 3.60 (m, 1H), 3.01 (s, 3H), 1.39 (s, 9H), 1.00 – 0.87 (m, 1H), 0.55 – 0.39 (m, 2H), 0.36 – 0.24 (m, 2H). LCMS: Method A (ESI-), rt (min): 0.76, [M-H]- m / z: 274.2, Purity: 100%. Example 3 6-(cyclopentoxy)-2-[(E,1S)-1-cyclopropyl-3-methylsulfonyl-allyl]-2,7- naphthyridin-1-one

[0238] (E,1S)-1-cyclopropyl-3-methylsulfonyl-prop-2-en-1-amine hydrochloride (70 mg, 0.331 mmol), DIPEA (0.150 mL, 0.859 mmol) and 6-(cyclopentoxy)-4-(2- oxoethyl)pyridine-3-carboxylic acid (55.0 mg, 0.221 mmol) were dissolved in anhydrous DMF (1.0 mL) and then 50 % T3P in ethyl acetate (0.410 mL, 0.696 mmol) was added and reaction was allowed to stir at RT for 20 min. The reaction mixture was purified directly using prep HPLC (Method 2, 215 nm) to afford 6-(cyclopentoxy)-2-[(E,1S)-1-cyclopropyl-3- methylsulfonyl-allyl]-2,7-naphthyridin-1-one (33 mg, 38% yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 9.03 (s, 1H), 7.70 (d, J = 7.6 Hz, 1H), 6.93 (dd, J = 15.3, 4.7 Hz, 1H), 6.90 – 6.88 (m, 1H), 6.82 (dd, J = 15.4, 1.5 Hz, 1H), 6.59 (d, J = 7.5 Hz, 1H), 5.49 – 5.37 (m, 1H), 4.82 – 4.72 (m, 1H), 3.03 (s, 3H), 2.05 – 1.90 (m, 2H), 1.79 – 1.67 (m, 4H), 1.67 – 1.51 (m, 3H), 0.84 – 0.72 (m, 1H), 0.69 – 0.59 (m, 1H), 0.58 – 0.47 (m, 1H), 0.35 – 0.25 (m, 1H). LCMS: Method A (ESI+), rt (min): 3.44, [M+H]+ m / z: 389.2, Purity: 100%.P383145WO June 2025 72 Example 4 – Synthesis of 2-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl-allyl]- 6-(cyclopentoxy)-2,7-naphthyridin-1-one tert-butyl N-[(1S)-1-[(3-chlorophenyl)methyl]-2-[methoxy(methyl)amino]-2-oxo- ethyl]carbamate

[0239] N-(tert-butoxycarbonyl)-3-chloro-L-phenylalanine (2.00 g, 6.67 mmol), N- methoxymethanamine hydrochloride (0.710 g, 7.28 mmol) and 50% T3P in ethyl acetate (4.00 mL, 6.72 mmol) were suspended in DCM (18 mL). DIPEA (2.90 mL, 16.6 mmol) was added and the reaction mixture was stirred for 1 h. The reaction mixture was diluted with saturated NaHCO3(aq) (20 mL) and the mixture was extracted with DCM (3 x 20 mL), combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (0-60% Ethyl acetate in heptane) to afford tert-butyl N-[(1S)-1-[(3-chlorophenyl)methyl]-2-[methoxy(methyl)amino]-2-oxo-ethyl]carbamate (2.06 g, 81% yield) as a yellow oil.1H NMR (400 MHz, CDCl3) δ 7.25 – 7.17 (m, 3H), 7.10 – 7.04 (m, 1H), 5.20 (d, J = 9.0 Hz, 1H), 5.00 – 4.88 (m, 1H), 3.72 (s, 3H), 3.20 (s, 3H), 3.05 (dd, J = 13.5, 6.0 Hz, 1H), 2.86 (dd, J = 13.5, 7.3 Hz, 1H), 1.42 (s, 9H). LCMS: Method A (ESI+), rt (min): 0.96, [M+H]+ m / z: 343.2, Purity: 98%. tert-butyl N-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl-allyl]carbamate

[0240] tert-butyl N-[(1S)-1-[(3-chlorophenyl)methyl]-2-[methoxy(methyl)amino]-2-oxo- ethyl]carbamate (2.07 g, 6.04 mmol) was dissolved in anhydrous THF (40 mL) under aP383145WO June 2025 73 nitrogen atmosphere, and cooled to 0 °C.2.4 M Lithium aluminium hydride in THF (5.30 mL, 12.7 mmol) was added slowly, and the mixture was stirred at 0 °C for 1 h. The reaction mixture was added dropwise to a mixture of ice (10 g), 1 M HCl(aq) (5 mL) and an aqueous solution of Rochelle's salt (5 mL). The aqueous phase was extracted with ethyl acetate (3 x 20 mL). Combined extracts were washed with brine, dried over Na2SO4and concentrated under reduced pressure to afford crude aldehyde. Diethyl [(methylsulfonyl)methyl]phosphonate (1.66 g, 7.21 mmol) was dissolved in THF (8 mL) and cooled to 0 °C under a nitrogen atmosphere. 3 M Methyl magnesium bromide in Et2O (2.30 mL, 6.90 mmol) was added dropwise, and the mixture stirred at 0 °C for 30 min. The freshly obtained aldehyde in THF (8 mL) was added dropwise, and the mixture was allowed to warm to RT over 2 h. Ethyl acetate (100 mL) was added, and the mixture was washed with 1 M HCl(aq)(2 × 20 mL) and brine, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using column chromtography (0-100% ethyl acetate in heptane increasing to 0-20% methanol in ethyl acetate). The isolated product was triturated with 20% ethyl acetate in heptane (20 mL) to afford tert-butyl N-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl-allyl]carbamate (0.510 g, 14% yield) as a white solid containing approximately 40% of the phosphonate as an impurity.1H NMR (400 MHz, DMSO-d6) δ 7.37 – 7.16 (m, 5H), 6.76 (dd, J = 15.2, 5.0 Hz, 1H), 6.67 (d, J = 15.4 Hz, 1H), 4.48 – 4.37 (m, 1H), 3.00 (s, 3H), 2.98 – 2.92 (m, 1H), 2.69 (dd, J = 13.5, 9.9 Hz, 1H), 1.29 (d, J = 9.5 Hz, 9H). LCMS: Method A (ESI+), rt (min): 0.91, [M+MeCN+Na]+ m / z: 423.3, 425.3, Purity: 96%. Example 4 2-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl-allyl]-6- (cyclopentoxy)-2,7-naphthyridin-1-one

[0241] tert-butyl N-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl- allyl]carbamate (126 mg, 0.210 mmol) was dissolved in 4 M hydrogen chloride in dioxane (0.53 mL, 2.11 mmol) and the reaction mixture was stirred at RT for 30 min. The mixture was then concentrated in vacuo. The obtained amine hydrochloride salt and 6-(cyclopentoxy)-4-(2- oxoethyl)pyridine-3-carboxylic acid (35.0 mg, 0.140 mmol) were dissolved in anhydrous DMF (1.0 mL) and then 50 % T3P in ethyl acetate (0.26 mL, 0.435 mmol) and DIPEA (0.10 mL,P383145WO June 2025 74 0.562 mmol) were added and reaction allowed to stir at RT for 20 min. The reaction mixture was purified directly using prep HPLC (Method 2, 215 nm) to afford 2-[(E,1S)-1-[(3- chlorophenyl)methyl]-3-methylsulfonyl-allyl]-6-(cyclopentoxy)-2,7-naphthyridin-1-one (38.7 mg, 58% yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 8.94 (d, J = 0.7 Hz, 1H), 7.62 (d, J = 7.6 Hz, 1H), 7.31 – 7.28 (m, 1H), 7.26 – 7.16 (m, 2H), 7.15 – 7.09 (m, 1H), 6.97 (dd, J = 15.4, 4.8 Hz, 1H), 6.83 (d, J = 0.7 Hz, 1H), 6.76 (dd, J = 15.4, 1.7 Hz, 1H), 6.53 (d, J = 7.5 Hz, 1H), 6.00 – 5.88 (m, 1H), 5.45 – 5.36 (m, 1H), 3.46 – 3.34 (m, 2H), 3.01 (s, 3H), 2.03 – 1.88 (m, 2H), 1.77 – 1.51 (m, 6H). LCMS: Method B (ESI+), rt (min): 4.00, [M+H]+ m / z: 473.2, 475.2, Purity: 100%. Example 5 – Synthesis of 2-[(E,1S)-1-[(3-chloro-4-hydroxy-phenyl)methyl]-3- methylsulfonyl-allyl]-6-(cyclopentoxy)-2,7-naphthyridin-1-one (2S)-2-(tert-butoxycarbonylamino)-3-[4-[tert-butyl(dimethyl)silyl]oxy-3-chloro- phenyl]propanoic acid

[0242] (2S)-2-(tert-butoxycarbonylamino)-3-(3-chloro-4-hydroxy-phenyl)propanoic acid (1.00 g, 3.17 mmol) and 1H-imidazole (0.431 g, 6.33 mmol) were dissolved in DCM (15 mL). tert-butyl(chloro)dimethylsilane (0.668 g, 4.43 mmol) was added and the reaction mixture was stirred at 40 °C for 5 h. DMF (1 mL) was added and the suspension stirred at 40 °C for 6 h. The suspension was retreated with 1H-imidazole (0.220 g, 3.23 mmol) and tert- butyl(chloro)dimethylsilane (0.350 g, 2.32 mmol), then stirred at RT overnight. The reaction mixture was diluted with water (10 mL) and the organic layer separated. The aqueous was extracted with DCM (1 x 15 mL), then the organic layers combined, dried over Na2SO4and concentrated under reduced pressure to afford crude (2S)-2-(tert-butoxycarbonylamino)-3-[4- [tert-butyl(dimethyl)silyl]oxy-3-chloro-phenyl]propanoic acid (2.13 g, 2.97 mmol, 94% yield) as a colourless oil that was used in the next step without any further purification. LCMS: Method A (ESI+), rt (min): 1.26, [M+H]+ m / z: 374.2, 376.2, Purity: 76%.P383145WO June 2025 75 tert-butyl N-[(1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy-3-chloro-phenyl]methyl]-2- [methoxy(methyl)amino]-2-oxo-ethyl]carbamate

[0243] (2S)-2-(tert-butoxycarbonylamino)-3-[4-[tert-butyl(dimethyl)silyl]oxy-3-chloro- phenyl]propanoic acid (3.12 g, 4.35 mmol), N-methoxymethanamine hydrochloride (637 mg, 6.53 mmol) and DIPEA (2.3 mL, 13.1 mmol) were stirred in DCM (15 mL), then 50% T3P in ethyl acetate (3.18 mL, 5.22 mmol) was added. The reaction mixture was stirred at room temperature overnight. The mixture was diluted with water (10 mL), then the aqueous mix extracted with DCM (2 x 10 mL). The organic extracts were combined, dried over Na2SO4and concentrated under reduced pressure. The residue was purified using automated column chromatography (5-100 % ethyl acetate in heptane) to afford tert-butyl N-[(1S)-1-[[4-[tert- butyl(dimethyl)silyl]oxy-3-chloro-phenyl]methyl]-2-[methoxy(methyl)amino]-2-oxo-ethyl] (1.70 g, 78% yield) as a colourless gum.1H NMR (400 MHz, DMSO-d6) δ 7.34 – 7.24 (m, 1H), 7.16 (d, J = 8.7 Hz, 1H), 7.08 (dd, J = 8.3, 2.2 Hz, 1H), 6.92 (d, J = 8.3 Hz, 1H), 4.61 – 4.41 (m, 1H), 3.71 (s, 3H), 3.16 – 3.01 (m, 3H), 2.78 (dd, J = 13.7, 4.3 Hz, 1H), 2.71 – 2.58 (m, 1H), 1.30 (s, 9H), 0.98 (s, 9H), 0.23 – 0.17 (m, 6H). LCMS: Method A (ESI+), rt (min): 1.33, [M+H]+ m / z: 473.3, 475.3, Purity: 100%. tert-butyl N-[(E,1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy-3-chloro-phenyl]methyl]-3- methylsulfonyl-allyl]carbamateP383145WO June 2025 76

[0244] tert-butyl N-[(1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy-3-chloro-phenyl]methyl]-2- [methoxy(methyl)amino]-2-oxo-ethyl]carbamate (1.70 g, 3.41 mmol) was dissolved in THF (15 mL) and cooled to 0 °C.2.4 M Lithium aluminium hydride in THF (2.8 mL, 6.83 mmol) was added and the mixture stirred for 45 mins. The mixture was added to 1 M HCl(aq), then filtered. The filtrate was extracted with ethyl acetate (3 x 15 mL). The organic fractions were combined, dried over Na2SO4and concentrated under reduced pressure to give the crude aldehyde. Diethyl [(methylsulfonyl)methyl]phosphonate (1.10 g, 4.78 mmol) was dissolved in THF (10 mL) and cooled to 0 °C.3 M Methyl magnesium bromide in diethyl ether (1.5 mL, 4.44 mmol) was added and the mixture stirred for 45 mins. A solution of the previously obtained aldehyde in THF (10 mL) was then added and mixture was stirred at 0 °C for 2 h. The reaction was quenched with 1M HCl(aq)to ~pH 5 and extracted with ethyl acetate (2 x 25 mL). The organic extracts were combined, dried over Na2SO4and concentrated under reduced pressure. The residue was purified using automated column chromatography (20 - 55 % ethyl acetate in heptane) to afford tert-butyl N-[(E,1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy- 3-chloro-phenyl]methyl]-3-methylsulfonyl-allyl]carbamate (894 mg, 43% yield) as a colourless oil.1H NMR (400 MHz, DMSO-d6) δ 7.36 – 7.26 (m, 1H), 7.17 (d, J = 8.9 Hz, 1H), 7.08 (dd, J = 8.3, 2.2 Hz, 1H), 6.91 (d, J = 8.3 Hz, 1H), 6.75 (dd, J = 15.2, 4.9 Hz, 1H), 6.66 (dd, J = 15.3, 1.3 Hz, 1H), 4.46 – 4.31 (m, 1H), 3.00 (s, 3H), 2.86 (dd, J = 13.6, 4.8 Hz, 1H), 2.59 (dd, J = 13.6, 10.0 Hz, 1H), 1.29 (s, 9H), 0.98 (s, 9H), 0.19 (s, 6H). LCMS: Method A (ESI+), rt (min): 1.27, [M+H]+ m / z: 434.2, 436.2, Purity: 100%. Example 5 2-[(E,1S)-1-[(3-chloro-4-hydroxy-phenyl)methyl]-3-methylsulfonyl-allyl]- 6-(cyclopentoxy)-2,7-naphthyridin-1-one

[0245] tert-butyl N-[(E,1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy-3-chloro-phenyl]methyl]- 3-methylsulfonyl-allyl]carbamate (250 mg, 0.408 mmol) was dissolved in a mixture of 4 M hydrogen chloride in dioxane (1.0 mL, 4.08 mmol) and methanol (1 mL) and stirred at room temperature for 4 h. The mixture was concentrated under reduced pressure, then re-dissolvedP383145WO June 2025 77 in anhydrous DMF (3 mL).6-(cyclopentoxy)-4-(2-oxoethyl)pyridine-3-carboxylic acid (110 mg, 0.353 mmol) was added, followed by DIPEA (0.28 mL, 1.63 mmol) and 50% T3P in ethyl acetate (0.75 mL, 1.26 mmol). The mixture was stirred at room temperature for 1 h, then diluted with water (10 mL) and extracted with ethyl acetate (2 x 10 mL). The organic extracts were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (55 - 80 % ethyl acetate in heptane). The residue was purified using prep HPLC (Method 1, 250 nm) followed by lyophilisation to afford 2-[(E,1S)-1-[(3-chloro-4-hydroxy-phenyl)methyl]-3-methylsulfonyl-allyl]- 6-(cyclopentoxy)-2,7-naphthyridin-1-one (49 mg, 23% yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 9.97 (s, 1H), 8.95 (s, 1H), 7.59 (d, J = 7.6 Hz, 1H), 7.17 (d, J = 2.1 Hz, 1H), 6.95 (dd, J = 15.4, 4.8 Hz, 1H), 6.91 (dd, J = 8.3, 2.1 Hz, 1H), 6.83 (s, 1H), 6.78 – 6.68 (m, 2H), 6.52 (d, J = 7.5 Hz, 1H), 5.91 – 5.80 (m, 1H), 5.46 – 5.36 (m, 1H), 3.27 (dd, J = 14.3, 5.9 Hz, 1H), 3.17 (dd, J = 14.2, 10.6 Hz, 1H), 3.00 (s, 3H), 2.02 – 1.88 (m, 2H), 1.77 – 1.65 (m, 4H), 1.65 – 1.52 (m, 2H). LCMS: Method B (ESI+), rt (min): 3.41, [M+H]+ m / z: 489.3, 491.3, Purity: 95%. Example 6 - Synthesis of 6-(cyclopentoxy)-2-[(E,1S)-1-[(4-hydroxy-3-methyl- phenyl)methyl]-3-methylsulfonyl-allyl]-2,7-naphthyridin-1-one methyl (2S)-3-(3-bromo-4-hydroxy-phenyl)-2-(tert-butoxycarbonylamino)propanoate

[0246] methyl N-(tert-butoxycarbonyl)-L-tyrosinate (4.00 g, 13.5 mmol) and 4- methylbenzenesulfonic acid monohydrate (258 mg, 1.36 mmol) were dissolved in anhydrous methanol (13.5 mL) and the reaction mixture was stirred for 10 min. A solution of N- bromosuccinimide (2.41 g, 13.5 mmol) in anhydrous Methanol (122 mL) was added dropwise from a foiled addition funnel over 20 minutes. The mixture was stirred for 5 min and then quenched with sat. sodium thiosulfate(aq) (5 mL) and then organics removed under reduce pressure. The aqueous solution was acidified to pH 4 with 2 M HCl(aq) and then extracted with DCM (3 x 40 mL). The extracts were combined, dried with brine and MgSO4, filtered and concentrated under reduced pressure. The residue was purified using automated columnP383145WO June 2025 78 chromatography (0-50% TBME in heptane) then again using automated column chromatography (isocratic 25% TBME in heptane) to afford methyl (2S)-3-(3-bromo-4- hydroxy-phenyl)-2-(tert-butoxycarbonylamino)propanoate (5.59 g, 83% yield) as a sticky colourless film that was used in the next reaction without any further purification.1H NMR (400 MHz, DMSO-d6) δ 10.05 (s, 1H), 7.36 – 7.33 (m, 1H), 7.27 (d, J = 8.1 Hz, 1H), 7.05 – 7.02 (m, 1H), 7.02 – 6.99 (m, 1H), 4.13 – 4.08 (m, 1H), 3.61 (s, 3H), 2.91 – 2.86 (m, 1H), 2.76 – 2.71 (m, 1H), 1.34 (s, 9H). LCMS: Method A (ESI+), rt (min): 0.88, [M-tBu+2H]+ m / z: 318.1, 320.1, Purity: 73%. methyl (2S)-3-[3-bromo-4-[tert-butyl(dimethyl)silyl]oxy-phenyl]-2-(tert- butoxycarbonylamino)propanoate

[0247] methyl (2S)-3-(3-bromo-4-hydroxy-phenyl)-2-(tert- butoxycarbonylamino)propanoate (5.58 g, 14.9 mmol) and 1H-imidazole (2.03 g, 29.8 mmol) were dissolved in DCM (100 mL) and then tert-butyl(chloro)dimethylsilane (4.51 g, 29.9 mmol) was added and the reaction mixture stirred at RT for 1 h. Further 1H-imidazole (2.03 g, 29.8 mmol) was added as well as DCM (30 mL) to improve solubilisation. The reaction was then allowed to stir for a further 14 h. The reaction mixture was diluted with water and the pH adjusted to ~2 with 2 M HCl(aq). The mixture was extracted with DCM (2 x 25 mL) and the combined extracts washed with 5% LiCl(aq)(10 mL), then dried with brine and MgSO4, filtered and concentrated to afford methyl (2S)-3-[3-bromo-4-[tert-butyl(dimethyl)silyl]oxy-phenyl]-2- (tert-butoxycarbonylamino)propanoate (7.15 g, 74% yield) as a yellow solid that was used in the next reaction without any further purification.1H NMR (400 MHz, DMSO-d6) δ 7.47 – 7.42 (m, 1H), 7.31 – 7.24 (m, 1H), 7.14 – 7.07 (m, 2H), 4.18 – 4.12 (m, 1H), 3.61 (s, 3H), 2.96 – 2.91 (m, 1H), 2.80 – 2.74 (m, 1H), 1.32 – 1.31 (m, 9H), 0.99 (s, 9H), 0.21 (s, 6H). LCMS: Method A (ESI+), rt (min): 1.37, [M-tBu+2H]+ m / z: 432.2434.2, Purity: 75%.P383145WO June 2025 79 tert-butyl N-[(E,1S)-1-[[3-bromo-4-[tert-butyl(dimethyl)silyl]oxy-phenyl]methyl]-3- methylsulfonyl-allyl]carbamate

[0248] Under a nitrogen atmosphere, methyl (2S)-3-[3-bromo-4-[tert- butyl(dimethyl)silyl]oxy-phenyl]-2-(tert-butoxycarbonylamino)propanoate (500 mg, 1.02 mmol) was dissolved in DCM (7 mL) and cooled to -78 °C.1 M DIBAL in toluene (2.0 mL, 2.00 mmol) was then added dropwise over 10 mins and stirred for 1 h 30 min. The reaction mixture was quenched with methanol (2 mL) and warmed to room temperature. Rochelle's salt(aq)(20 mL) and 2 M HCl(aq)(3 mL) were added the mixture filtered. The filtrate was transferred to a separating funnel and the organics separated. The aqueous was extracted with DCM (2 x 15 mL) and the organic extracts combined, dried over Na2SO4and concentrated to give crude aldehyde. Diethyl [(methylsulfonyl)methyl]phosphonate (260 mg, 1.13 mmol) was dissolved in THF (4 mL) and cooled to 0 °C under a nitrogen atmosphere.3 M Methyl magnesium bromide dropwise, and the mixture was stirred at 0 °C for 30 min. Crude aldehyde in THF (3 mL) was added dropwise, and the mixture was stirred for 20 min while slowly warming to RT. After this time, saturated NH4Cl(aq)(4 mL) and ethyl acetate (50 mL) were added, and the mixture was washed with 1 M HCl(aq)(2 × 15 mL) and brine (20 mL), dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (0-50% TBME in heptane) to afford tert-butyl N-[(E,1S)-1-[[3-bromo-4-[tert- butyl(dimethyl)silyl]oxy-phenyl]methyl]-3-methylsulfonyl-allyl]carbamate (360 mg, 43% yield) as a colourless film.1H NMR (400 MHz, DMSO-d6) δ 7.24 – 7.21 (m, 1H), 6.97 – 6.94 (m, 1H), 6.92 – 6.90 (m, 1H), 6.89 – 6.86 (m, 1H), 6.50 – 6.46 (m, 1H), 6.44 – 6.40 (m, 1H), 4.20 – 4.15 (m, 1H), 2.79 (s, 3H), 2.67 – 2.61 (m, 1H), 2.47 – 2.39 (m, 1H), 1.09 – 1.07 (m, 9H), 0.78 (s, 9H), 0.00 (s, 6H). LCMS: Method A (ESI+), rt (min): 1.29, [M-tBu+2H]+ m / z: 478.3, Purity: 75%.P383145WO June 2025 80 tert-butyl N-[(E,1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy-3-methyl-phenyl]methyl]-3- methylsulfonyl-allyl]carbamate

[0249] To a solution of 50% trimethylboroxin in THF (0.140 mL, 0.501 mmol) and caesium carbonate (165 mg, 0.506 mmol) was added a solution of tert-butyl N-[(E,1S)-1-[[3- bromo-4-[tert-butyl(dimethyl)silyl]oxy-phenyl]methyl]-3-methylsulfonyl-allyl]carbamate (120 mg, 0.168 mmol) in anhydrous 1,4-Dioxane (4.0 mL). Water (1.0 mL) was added and the reaction mixture was sparged with N2for 5 minutes before adding Pd(dppf)Cl2•CH2Cl2(14.0 mg, 0.0169 mmol). The reaction mixture was sparged again for 5 minutes and heated to 95 °C overnight. The reaction mixture was filtered through celite and extracted with ethyl acetate (10 mL). The reaction mixture was diluted with water (5 mL) and the aqueous was extracted with further ethyl acetate (2 x 10 mL). The organics extracts were dried with brine and MgSO4, filtered and concentrated under a reduced pressure. The residue was purified using automated column chromatography (0-100% TBME in heptane) to afford tert-butyl N-[(E,1S)-1-[[4-[tert- butyl(dimethyl)silyl]oxy-3-methyl-phenyl]methyl]-3-methylsulfonyl-allyl]carbamate (50.0 mg, 37% yield) as a colourless oil.1H NMR (400 MHz, DMSO-d6) δ 7.31 (d, J = 4.9 Hz, 1H), 7.16 (s, 1H), 6.99 (s, 1H), 6.91 (d, J = 8.0 Hz, 1H), 6.70 – 6.68 (m, 1H), 6.63 (s, 1H), 4.37 (s, 1H), 2.97 (s, 3H), 2.79 (d, J = 5.6 Hz, 1H), 2.62 (s, 1H), 2.11 (s, 3H), 1.31 (d, J = 2.9 Hz, 9H), 0.97 (s, 9H), 0.17 (s, 6H). LCMS: Method E (ESI+), rt (min): 1.20, [M+Na]+ m / z: 492.2, Purity: 54%.P383145WO June 2025 81 Example 6 6-(cyclopentoxy)-2-[(E,1S)-1-[(4-hydroxy-3-methyl-phenyl)methyl]-3- methylsulfonyl-allyl]-2,7-naphthyridin-1-one

[0250] tert-butyl N-[(E,1S)-1-[[4-[tert-butyl(dimethyl)silyl]oxy-3-methyl-phenyl]methyl]- 3-methylsulfonyl-allyl]carbamate (50 mg, 0.0671 mmol) was dissolved in 4 M hydrogen chloride in dioxane (0.19 mL, 0.760 mmol) and Methanol (0.10 mL) and stirred at 45 °C for 2 hours before being concentrated under reduced pressure. To the residue was then added 6- (cyclopentoxy)-4-(2-oxoethyl)pyridine-3-carboxylic acid (22 mg, 0.0618 mmol) and DMF (0.40 mL) and stirred for 1 min. DIPEA (0.05 mL, 0.287 mmol) was added and the mixture stirred for a further minute. 50% T3P in ethyl acetate (0.11 mL, 0.185 mmol) was added and the mixture allowed to stir for 5 min at RT. The reaction mixture was concentrated under reduced pressure and the residue suspended in water, then extracted with ethyl acetate (3 x 10 mL). Organic extracts were washed with brine, dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified using prep HPLC (Method 1, 215 nm) and lyophilised to afford 6-(cyclopentoxy)-2-[(E,1S)-1-[(4-hydroxy-3-methyl-phenyl)methyl]-3- methylsulfonyl-allyl]-2,7-naphthyridin-1-one (5.1 mg, 18% yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 9.09 (s, 1H), 8.95 (s, 1H), 7.58 (d, J = 7.6 Hz, 1H), 6.97 – 6.90 (m, 1H), 6.88 – 6.85 (m, 1H), 6.83 (s, 1H), 6.78 – 6.74 (m, 1H), 6.72 – 6.65 (m, 1H), 6.56 (d, J = 8.1 Hz, 1H), 6.50 (d, J = 7.6 Hz, 1H), 5.84 – 5.77 (m, 1H), 5.44 – 5.38 (m, 1H), 3.24 – 3.18 (m, 1H), 3.14 – 3.05 (m, 1H), 2.98 (s, 3H), 1.98 (s, 3H), 1.96 – 1.89 (m, 2H), 1.74 – 1.65 (m, 4H), 1.63 – 1.55 (m, 2H). LCMS: Method B (ESI+), rt (min): 3.37, [M+H]+ m / z: 469.3, Purity: 100%.P383145WO June 2025 82 Example 7 - Synthesis of 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-3- tetrahydropyran-4-yl-2,7-naphthyridin-1-one 6-(cyclopentoxy)-4-(2-oxo-2-tetrahydropyran-4-yl-ethyl)pyridine-3-carboxylic acid

[0251] 2 M n-butyllithium in hexanes (1.1 mL, 2.25 mmol) was added to a -20 °C solution of diisopropylamine (0.33 mL, 2.36 mmol) in THF (1.5 mL). The mixture was stirred for 15 mins, then cooled to -78 °C. A solution of 6-(cyclopentoxy)-4-methyl-pyridine-3- carboxylic acid (250 mg, 1.07 mmol) in anhydrous THF (2 mL) was added dropwise, and the mixture stirred for 30 mins at -78 °C and -20 °C for 15 mins. The solution was re-cooled to - 78 °C and a solution of N-methoxy-N-methyl-tetrahydropyran-4-carboxamide (186 mg, 1.07 mmol) in THF (0.5 mL) was added. The mixture was stirred at -78 °C for 40 mins, then warmed to RT and stirred for 2 h.1 M HCl(aq)was added until ~pH 4 was achieved and the resulting mixture was extracted with ethyl acetate (2 x 10 mL). The organic extracts were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (0-60% ethyl acetate in heptane) to afford 6-(cyclopentoxy)-4-(2-oxo-2-tetrahydropyran-4-yl-ethyl)pyridine-3-carboxylic acid (179 mg, 46% Yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 12.83 (s, 1H), 8.67 (s, 1H), 6.67 (s, 1H), 5.43 (tt, J = 6.0, 2.8 Hz, 1H), 4.17 (s, 2H), 3.87 (ddd, J = 11.4, 4.4, 2.3 Hz, 2H), 3.37 (dd, J = 11.6, 2.2 Hz, 2H), 1.95 (tt, J = 10.1, 4.6 Hz, 2H), 1.86 – 1.40 (m, 10H). LCMS: Method C (ESI+), rt (min): 0.86, [M+H]+ m / z: 334.2, Purity: 100%.P383145WO June 2025 83 Example 7 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-3-tetrahydropyran-4-yl-2,7- naphthyridin-1-one

[0252] 50% T3P in ethyl acetate (240 µL, 0.407 mmol) was added to a mixture of 6- (cyclopentoxy)-4-(2-oxo-2-tetrahydropyran-4-yl-ethyl)pyridine-3-carboxylic acid (45 mg, 0.135 mmol), [(E)-3-methylsulfonylallyl]ammonium chloride (35 mg, 0.202 mmol) and DIPEA (94 uL, 0.540 mmol) in anhydrous DMF (1.0 mL) and the reaction was stirred for 2 hours at RT. The mixture was retreated with [(E)-3-methylsulfonylallyl]ammonium chloride (17 mg, 0.101 mmol), 50% T3P in ethyl acetate (80 µL, 0.136 mmol) and DIPEA (50 µL, 0.286 mmol) then stirred at 50 °C for 7 h. The reaction was retreated with 50% T3P in ethyl acetate (80 µL, 0.14 mmol) and stirred at 50 °C for 3 hours. The reaction was retreated a final time with 50% T3P in ethyl acetate (80 µL, 0.135 mmol) and stirred 10 hours at 65 °C. The reaction mixture was diluted with 5% w / w LiCl(aq) (3 mL) and the aqueous mix extracted with DCM (2 x 3 mL). The organic extracts were combined and concentrated under reduced pressure. The residue was purified using prep HPLC (Method 3, 254 nm) followed by lyophilisation to afford 6- (cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-3-tetrahydropyran-4-yl-2,7-naphthyridin-1-one (18.0 mg, 31% yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 9.00 (s, 1H), 6.94 (dt, J = 15.4, 3.9 Hz, 1H), 6.84 (s, 1H), 6.59 (s, 1H), 6.52 (dt, J = 15.2, 1.8 Hz, 1H), 5.47 – 5.39 (m, 1H), 5.00 (dd, J = 4.1, 2.0 Hz, 2H), 3.92 (dd, J = 11.4, 3.8 Hz, 2H), 3.52 – 3.42 (m, 2H), 2.97 (s, 3H), 2.81 – 2.70 (m, 1H), 2.05 – 1.91 (m, 2H), 1.83 – 1.56 (m, 10H). LCMS: Method B (ESI+), rt (min): 3.13, [M+H]+ m / z: 433.4, Purity: 100%.P383145WO June 2025 84 Example 8 – Synthesis of 3-benzyl-6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7- naphthyridin-1-one 6-(cyclopentoxy)-4-(2-oxo-3-phenyl-propyl)pyridine-3-carboxylic acid

[0253] 2 M n-butyllithium in hexanes (1.6 mL, 3.20 mmol) was added to a -20 °C solution of diisopropylamine (0.45 mL, 3.21 mmol) in THF (1.5 mL). The mixture was stirred for 15 mins, then cooled to -78 °C. A solution of 6-(cyclopentoxy)-4-methyl-pyridine-3- carboxylic acid (250 mg, 1.07 mmol) in THF (2 mL) and added dropwise to the mixture and stirred for 30 mins at -78 °C then -20 °C for 15 mins. The solution was re-cooled to -78 °C and a solution of N-methoxy-N-methyl-2-phenyl-acetamide (190 mg, 1.06 mmol) in THF (0.5 mL) was added. The mixture was stirred at for 20 mins, then warmed to RT and stirred for 1.5 h.1 M HCl(aq)was added until ~pH 4 was achieved and the mixture extracted with ethyl acetate (2 x 10 mL). The organic extracts were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by automated column chromatography (0- 100% ethyl acetate in heptane) to afford 6-(cyclopentoxy)-4-(2-oxo-3-phenyl-propyl)pyridine- 3-carboxylic acid (EV-YYR001-036-001) (197 mg, 0.580 mmol, 54% Yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 12.92 (s, 1H), 8.68 (s, 1H), 7.35 – 7.29 (m, 2H), 7.27 – 7.18 (m, 3H), 6.67 (s, 1H), 5.42 (tt, J = 6.0, 2.8 Hz, 1H), 4.15 (s, 2H), 3.89 (s, 2H), 2.04 – 1.84 (m, 2H), 1.82 – 1.52 (m, 6H). LCMS: Method D (ESI+), rt (min): 3.78, [M+H]+ m / z: 340.2, Purity: 98%. Example 8 3-benzyl-6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin- 1-oneP383145WO June 2025 85

[0254] 50% T3P in ethyl acetate (210 uL, 0.356 mmol) was added to a mixture of 6- (cyclopentoxy)-4-(2-oxo-3-phenyl-propyl)pyridine-3-carboxylic acid (40 mg, 0.118 mmol), [(E)- 3-methylsulfonylallyl]ammonium chloride (30.3 mg, 0.177 mmol) and DIPEA (80 µL, 0.459 mmol) in anhydrous DMF (0.90 mL) and the reaction was stirred for 2 h at RT. The mixture was retreated with [(E)-3-methylsulfonylallyl]ammonium chloride (15 mg, 0.0874 mmol), DIPEA (0.040 mL, 0.229 mmol) and 50% T3P in ethyl acetate (100 µL, 0.170 mmol) then stirred at 65 °C overnight. The reaction mixture was re-treated with 50% T3P in ethyl acetate (150 µL, 0.255 mmol) and stirred at 65 °C for 2 h. The reaction was re-treated with 50% T3P in ethyl acetate (150 µL, 0.255 mmol) and stirred at 65 °C for 2 h. The reaction mixture was washed with water (3 mL) and the aqueous back extracted with DCM (2 x 3 mL). The organic extracts were combined and concentrated under reduced pressure. The residue was purified using prep HPLC (Method 3, 254 nm) followed by lyophilisation to afford 3-benzyl- 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one (11 mg, 19% Yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 9.01 (s, 1H), 7.40 – 7.34 (m, 2H), 7.32 – 7.25 (m, 3H), 6.80 (d, J = 0.8 Hz, 1H), 6.75 (dt, J = 15.4, 4.1 Hz, 1H), 6.47 (dt, J = 15.4, 1.9 Hz, 1H), 6.37 (s, 1H), 5.47 – 5.40 (m, 1H), 4.80 (s, 2H), 4.02 (t, J = 1.6 Hz, 2H), 2.92 (s, 3H), 2.00 – 1.94 (m, 2H), 1.80 – 1.52 (m, 6H). LCMS: Method B (ESI+), rt (min): 3.86, [M+H]+ m / z: 439.3, Purity: 100%. Example 9 – synthesis of 6-(cyclopentoxy)-3-methyl-2-[(E)-3-methylsulfonylallyl]-2,7- naphthyridin-1-one 4-acetonyl-6-(cyclopentoxy)pyridine-3-carboxylic acid

[0255] 2.5 M n-butyllithium in hexanes (1.1 mL, 2.71 mmol) was added to a -20 °C solution of diisopropylamine (0.40 mL, 2.83 mmol) in THF (2 mL). The mixture was stirred for 15 mins, then cooled to -78 °C. A solution of 6-(cyclopentoxy)-4-methyl-pyridine-3-carboxylic acid (300 mg, 1.29 mmol) in THF (3 mL) and added to the mixture and stirred for 30 mins at - 78 °C and -20 °C for 15 min. The solution was re-cooled to -78 °C and N-methoxy-N- methylacetamide (0.137 mL, 1.29 mmol) was added. The mixture was stirred at -78 °C for 20 min, then at RT for 1 h. The mixture was quenched with 1 M HCl(aq)(adjusted to ~pH 4) andP383145WO June 2025 86 extracted with ethyl acetate (3 x 10 mL). The organic extracts were combined, dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified using automated column chromatography (25-60% ethyl acetate in heptane with 1% acetic acid), then again using reverse phase automated column chromatography (35-55% acetonitrile in water with 0.1% formic acid) to afford 4-acetonyl-6-(cyclopentoxy)pyridine-3-carboxylic acid (176 mg, 42% Yield) as a white powder.1H NMR (400 MHz, DMSO-d6) δ 12.85 (s, 1H), 8.67 (s, 1H), 6.66 (s, 1H), 5.52 – 5.33 (m, 1H), 4.17 – 4.00 (m, 2H), 2.17 (s, 3H), 2.02 – 1.86 (m, 2H), 1.76 – 1.64 (m, 4H), 1.64 – 1.54 (m, 2H). LCMS: Method B (ESI+), rt (min): 2.69, [M+H]+ m / z: 264.0, Purity: 80%. Example 9 6-(cyclopentoxy)-3-methyl-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin- 1-one

[0256] 50% T3P in ethyl acetate (235 µL, 0.4 mmol) was added to a mixture of 4- acetonyl-6-(cyclopentoxy)pyridine-3-carboxylic acid (35 mg, 0.13 mmol) , [(E)-3- methylsulfonylallyl]ammonium chloride (34 mg, 0.199 mmol) and DIPEA (93 µL, 0.532 mmol) in anhydrous DMF (1 mL) and the reaction was stirred for 2 hours at RT. The reaction mixture was retreated with [(E)-3-methylsulfonylallyl]ammonium chloride (11 mg, 0.07 mmol), 50% T3P in ethyl acetate (117 uL, 0.199 mmol) and DIPEA (46 uL, 0.266 mmol) then stirred at 50 °C for 7 hours. The reaction mixture was washed with water (3 mL) and the aqueous back extracted with DCM (2 x 3 mL). The organic extracts were combined and concentrated under reduced pressure. The residue was purified using Prep HPLC (Method 3) followed by lyophilisation to afford 6-(cyclopentoxy)-3-methyl-2-[(E)-3-methylsulfonylallyl]-2,7- naphthyridin-1-one (17 mg, 35% Yield) as a white powder.1H NMR (500 MHz, DMSO-d6) δ 8.98 (s, 1H), 6.89 (dt, J = 15.4, 4.1 Hz, 1H), 6.75 (s, 1H), 6.58 – 6.51 (m, 1H), 6.43 (s, 1H), 5.47 – 5.40 (m, 1H), 4.93 – 4.86 (m, 2H), 2.98 (s, 3H), 2.33 (s, 3H), 2.02 – 1.90 (m, 2H), 1.77 – 1.66 (m, 4H), 1.65 – 1.56 (m, 2H). LCMS: Method B (ESI+), rt (min): 3.04, [M+H]+ m / z: 363.2, Purity: 100%.P383145WO June 2025 87 EXAMPLES 10 to 15 General Scheme 1

[0257] Step 1: Optionally 1-substituted tert‐butyl N‐[(2E)‐3‐methanesulfonyl‐prop‐2‐ en‐1‐yl]carbamates. Addition of a solution of N-BOC aminoacetaldehyde to 1 equivalent of diethyl methanesulfonylmethylphosphonate and 1 eq of sodium hydride with stirring in anhydrous THF at 0 °C, followed by warming to room temperature and stirring for 1 hour, affords the desired N-protected vinyl sulfone after flash column chromatography.

[0258] Step 2: Optionally 1-substituted (2E)‐3‐methanesulfonylprop‐2‐en‐1‐amines. Deprotection is achieved by treatment with TFA in dichloromethane at 0 °C for 1 hour. General Scheme 2Step 1: Treatment of beta-keto ester with triethyl orthoformate (3 eq) and acetic anhydride (1.6 eq) at 100 °C for 18 hours affords the optionally substituted ethyl 2‐ (ethoxymethylidene)‐3‐oxo butanoate. Step 2: Reaction of step 1 product with substituted amidine in the presence of excess sodium carbonate in ethanol heated to reflux for 2 hours affords the desired substituted pyrimidine ester. Step 3: Treatment of step 2 product with N,N-dimethylformamide dimethyl acetal (3 eq) in DMF at 130 °C for 2 hours affords the desired substituted ethyl 4‐[2‐(dimethylamino)‐ ethenyl]‐pyrimidine‐5‐carboxylate.P383145WO June 2025 88 Step 4: Treatment of step 3 product with the desired optionally 1-substituted (2E)‐3‐ methanesulfonylprop‐2‐en‐1‐amines in acetic acid heated to reflux for 2 hours affords the desired 6‐[(2E)‐3‐methanesulfonyl‐1‐substituted prop‐2‐en‐1‐yl]‐2,8‐disubstituted pyrido[4,3‐ d]pyrimidin‐5‐one after purification by flash column chromatography. Racemic samples can be subjected to preparative chiral supercritical fluid chromatography under standard conditions to provide separated R and S isomers. Example 10 - Synthesis of 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one (E)-3-(methylsulfonyl)prop-2-en-1-amineTo a solution of tert-Butyl N-[(E)-3-methylsulfonylallyl]carbamate (1.21 g, 5.14mmol) in DCM (15 mL) was cooled to 0°C for 10 mins. TFA (15 mL) was added dropwise slowly, the mixture was stirred at 0°C for 1.5 h. TLC showed the reaction was completed. The mixture was concentrated in vacuo to obtain the crude of desired product as the TFA salt (2.1 g) as brown oil.1H NMR (400 MHz, DMSO-d6) δ 6.99 (dt, J = 15.2, 1.6 Hz, 1H), 6.75 (dt, J = 15.6, 5.6 Hz, 1H), 3.76 (d, J = 5.6 Hz, 2H), 3.04 (s, 3H). Ethyl (E)-2-(ethoxymethylene)-3-oxo-4-phenylbutanoateA solution of ethyl 3-oxo-4-phenylbutanoate (2.0 g, 9.70 mmol), triethoxymethane (4.31 g, 29.1 mmol) and Ac2O (1.58 g, 15.5 mmol). The mixture was stirred at 100°C overnight. Water (30 mL) was added into the reaction solution, and extracted with ethyl acetate (30 mL x 3). The combined organic layers were washed with brine (100 mL), dried over Na2SO4, filtered and the filtrate was concentrated in vacuo, the residue was purified by column chromatography (petroleum ether / ethyl acetate 92 / 8, v / v) to obtain the desired product (1.0 g, 50 % yield) as yellow oil.P383145WO June 2025 89 Ethyl 4-benzyl-2-(tert-butyl)pyrimidine-5-carboxylateTo a solution of ethyl 2-(ethoxymethylene)-3-oxo-4-phenylbutanoate (700 mg, 2.67 mmol), pivalimidamide hydrochloride (365 mg, 2.67 mmol), Na2CO3 (707.6 mg, 6.67 mmol) in EtOH (10 mL), the mixture was stirred at 90°C for 2h. TLC and LCMS showed the reaction was completed. The reaction mixture was concentrated in vacuo, the residue was purified by column chromatography (petroleum ether / ethyl acetate 85 / 15, v / v) to obtain the desired product (450 mg, 56.7% yield) as yellow oil. LC-MS (Agilent-Acid): Rt:2.47 min; m / z: [M+H]+ 299.3. Ethyl (E)-2-(tert-butyl)-4-(2-(dimethylamino)-1-phenylvinyl)pyrimidine-5-carboxylateTo a solution of ethyl 4-benzyl-2-(tert-butyl)pyrimidine-5-carboxylate (200 mg, 0.7 mmol), DMF-DMA (240 mg, 2.0 mmol) in DMF (6 mL), the mixture was stirred at 130°C for 2h. TLC and LCMS showed the reaction was completed. H2O (20 mL) was added to the reaction solution, extracted with ethyl acetate (20 mL x 3). The combined organic layers were washed with brine (30 mL), dried over Na2SO4, filtered and the filtrate was concentrated in vacuo to obtain the crude of desired product (150 mg, 63.7%) as yellow oil. LC-MS (Waters-Base): Rt:1.75 min; m / z: [M+H]+ 354.4.P383145WO June 2025 90 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐oneTo a solution of ethyl (E)-2-(tert-butyl)-4-(2-(dimethylamino)-1-phenylvinyl)pyrimidine-5- carboxylate (150 mg, 0.42 mmol), (E)-3-(methylsulfonyl)prop-2-en-1-amine TFA salt (45.6 mg, 0.50 mmol) in AcOH (3 mL), the mixture was stirred at 110°C for 2h. TLC and LCMS showed the reaction was completed. The solution pH was adjusted to ~9 by saturated NaHCO3 (100 mL), and was extracted with ethyl acetate (30 mL x3), the combined organic layer was concentrated in vacuo, the residue was purified by column chromatography (petroleum ether / ethyl acetate 50 / 50, v / v) to obtain the desired product (26 mg, 0.68 mmol, 15.5% yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 9.54 (s, 1H), 8.15 (s, 1H), 7.79 – 7.70 (m, 2H), 7.48 (dd, J = 8.4, 6.8 Hz, 2H), 7.45 – 7.32 (m, 1H), 6.94 (dt, J = 15.5, 4.3 Hz, 1H), 6.76 (dt, J = 15.4, 1.8 Hz, 1H), 4.94 (dd, J = 4.4, 1.8 Hz, 2H), 2.98 (s, 3H), 1.38 (s, 9H). UPLC (Waters-Acid): Rt:4.77 min; 254 nm: 100 % purity; 214 nm: 100 % purity. LC- MS (Agilent-Acid): Rt:2.14 min; m / z: [M+H]+ 398.1. Example 11 and 11b - Synthesis of 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐ methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one and 2‐tert‐butyl‐ 6‐[(1S,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one 2‐tert‐butyl‐6‐[(2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐oneTo a solution of ethyl (E)-2-(tert-butyl)-4-(2-(dimethylamino)-1-phenylvinyl)pyrimidine-5- carboxylate (400 mg, 1.13 mmol), (E)-1-cyclopropyl-3-(methylsulfonyl)prop-2-en-1-amineP383145WO June 2025 91 (198.2 mg, 1.13 mmol) in AcOH (3 mL), the mixture was stirred at 110°C for 2h. TLC and LCMS showed the reaction was completed. The solution was adjusted to pH~9 by saturated NaHCO3 (100 mL), and was extracted with ethyl acetate (30 mL x3), the combined organic layer was concentrated in vacuo, the residue was purified by column chromatography (petroleum ether / ethyl acetate =50 / 50, v / v) to obtain the desired product (300 mg, 0.68 mmol, 60.7 % yield) as a white solid. Example 11 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one2‐tert‐butyl‐6‐[(2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one was purified by chiral SFC (Mobile phase CO2 / methanol(10% MeCN) (45 / 55)) to give 120 mg Example 11 and 130 mg Example 11b. Example 11 was confirmed as the R enantiomer by comparing with material analogously synthesised from chirally pure (R,E)-1-cyclopropyl-3-(methylsulfonyl)prop-2-en-1-amine as starting material.1H NMR (400 MHz, DMSO-d6) δ 9.53 (s, 1H), 8.21 (s, 1H), 7.78 – 7.69 (m, 2H), 7.50 – 7.43 (m, 2H), 7.42 – 7.34 (m, 1H), 7.05 (dd, J = 15.2, 4.8 Hz, 1H), 6.93 (dd, J = 15.2, 1.6 Hz, 1H), 4.82-4.78 (m, 1H), 3.03 (s, 3H), 1.87 – 1.75 (m, 1H), 1.37 (s, 9H), 0.79 (td, J = 8.8, 4.0 Hz, 1H), 0.68 (dt, J = 9.6, 4.8 Hz, 1H), 0.58 (td, J = 8.8, 4.0 Hz, 1H), 0.38 (dt, J = 10.4, 5.2 Hz, 1H). UPLC (Waters- Acid): Rt:4.77 min; 254 nm:99.4% purity; 214 nm: 99.4% purity. LC-MS (Agilent- Acid): Rt:2.27 min; m / z: [M+H]+ =438.1. UPCC Rt:1.25 min (Mobile phase CO2 / methanol(45 / 55).P383145WO June 2025 92 Example 11b 2‐tert‐butyl‐6‐[(1S,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one1H NMR (400 MHz, DMSO-d6) δ 9.53 (s, 1H), 8.21 (s, 1H), 7.78 – 7.69 (m, 2H), 7.50 – 7.43 (m, 2H), 7.42 – 7.34 (m, 1H), 7.05 (dd, J = 15.2, 4.8 Hz, 1H), 6.93 (dd, J = 15.2, 1.6 Hz, 1H), 4.82-4.78 (m, 1H), 3.03 (s, 3H), 1.87 – 1.75 (m, 1H), 1.37 (s, 9H), 0.79 (td, J = 8.8, 4.0 Hz, 1H), 0.68 (dt, J = 9.6, 4.8 Hz, 1H), 0.58 (td, J = 8.8, 4.0 Hz, 1H), 0.38 (dt, J = 10.4, 5.2 Hz, 1H). UPLC (Waters-Acid): Rt:4.77 min; 254 nm:99.1% purity; 214 nm: 98.7% purity. LC-MS (Agilent-Acid): Rt:2.27 min; m / z: [M+H]+ =438.1. UPCC Rt:2.02 min (Mobile phase CO2 / methanol(45 / 55). Example 12 - Synthesis of 2‐(1,1‐difluoroethyl)‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐ yl]‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one 2,2-difluoropropanimidamideTo a solution of NH4Cl (5.81 g, 108.65 mmol) in Toluene (60 mL) cooled to 0°C for 30 mins, was slowly added dropwise Al(Et)3 (2M in Hexane, 60 mL). After addition, the mixture was stirred at room temperature for 30 mins, until no further evolution of gas. Ethyl 2,2- difluoropropanoate (3 g, 21.73 mmol) was added and the mixture was stirred at 80°C overnight under argon atmosphere. TLC showed the reaction was complete. The reaction mixture was cooled to 0°C, and MeOH (120 mL) was added slowly, and stirred at 0°C for 1h. The mixture was filtered and the filter cake was washed by MeOH (1000 mL). The filtrate was concentrated in vacuum to obtain the crude desired product (750 mg, 1.67 mmol, 32.1% yield) as a yellow solid.1H NMR (400 MHz, Methanol-d4) δ 1.99 – 1.83 (m, 3H).P383145WO June 2025 93 Ethyl 4-benzyl-2-(1,1-difluoroethyl)pyrimidine-5-carboxylate2,2-Difluoropropanimidamide (750 mg, 6.94 mmol) and Na2CO3 (1.83 g, 17.4 mmol) in EtOH (20 mL) was stirred at room temperature for 30 mins before ethyl (E)-2- (ethoxymethylene)-3-oxo-4-phenylbutanoate (1.81 g, 6.94 mmol) was added. The mixture was stirred at 90°C overnight. TLC and LCMS showed the reaction was completed. The mixture was concentrated in vacuo, and the residue was purified by column chromatography (petroleum ether / ethyl acetate 85 / 15, v / v / ) to obtain the desired product (170 mg, 0.55 mmol, 10.1% yield) as a white solid.1H NMR (400 MHz, Chloroform-d) δ 9.20 (s, 1H), 7.33 – 7.26 (m, 4H), 7.23 – 7.17 (m, 1H), 4.60 (s, 2H), 4.39 (d, J = 7.2 Hz, 2H), 2.13 – 2.01 (m, 4H), 1.36 (t, J = 7.2 Hz, 3H). Ethyl (E)-2-(1,1-difluoroethyl)-4-(2-(dimethylamino)-1-phenylvinyl)pyrimidine-5-carboxylateTo a solution of ethyl 4-benzyl-2-(1,1-difluoroethyl)pyrimidine-5-carboxylate (170 mg, 0.55 mmol) in DMF (3 mL) was added DMF-DMA (198.5 mg, 1.66 mmol). The mixture was stirred at 130°C for 2h. TLC and LCMS showed the reaction was completed. The mixture was cooled to 0°C, water H2O (10 mL) was added and extracted with ethyl acetate (10 mL x 3). The combined organic layers were washed with brine (30 mL), dried over Na2SO4, filtered and the filtrate was concentrated in vacuo to obtained the crude desired product (210 mg, 0.58 mmol, 105 % yield) as a yellow oil. LC-MS (Waters-Base): Rt:1.31 min; m / z: [M+H]+ 362.2.P383145WO June 2025 94 2‐(1,1‐difluoroethyl)‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐oneA solution of ethyl (E)-2-(1,1-difluoroethyl)-4-(2-(dimethylamino)-1-phenylvinyl)pyrimidine-5- carboxylate (100 mg, 0.27 mmol), (E)-3-(methylsulfonyl)prop-2-en-1-amine (37.4 mg, 0.27 mmol) in AcOH (2 mL) was heated with stirring at 110°C for 3 h. TLC and LCMS showed the reaction was completed. The mixture was cooled to 0°C, before adding saturated sodium bicarbonate solution to pH 8, extracted with ethyl acetate (10 mL x 3). The combined organic layers were washed by brine (30 mL), dried over Na2SO4, filtered, the filtrate was concentrated in vacuo, the residue was purified by Prep-TLC to obtained the crude of desired product (45 mg, 0.11 mmol, 41.4 % yield) as a white solid.1H NMR (400 MHz, DMSO-d6) δ 9.70 (s, 1H), 8.27 (s, 1H), 7.73 – 7.64 (m, 2H), 7.50 (t, J = 7.6 Hz, 2H), 7.45 – 7.37 (m, 1H), 6.95 (dt, J = 15.2, 4.4 Hz, 1H), 6.84 – 6.74 (m, 1H), 4.97 (dd, J = 4.4, 2.0 Hz, 2H), 2.98 (s, 3H), 2.05 (t, J = 19.2 Hz, 3H). UPLC (Waters-Base): Rt:3.608min; 254 nm:96.57 % of purity; 214 nm: 96.82 % of purity. LC-MS (Agilent-Acid): Rt:1.981 min; m / z: calculated for [M+H] + =406.1, found 406.1. Example 13 and 13b Synthesis of 6‐[(1R,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐ en‐1‐yl]‐2‐(1,1‐difluoroethyl)‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one and 6‐[(1S,2E)‐1‐ cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐difluoroethyl)‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one To a solution of ethyl (E)-2-(1,1-difluoroethyl)-4-(2-(dimethylamino)-1-phenylvinyl)pyrimidine- 5-carboxylate (70 mg, 0.194 mmol) and (E)-1-cyclopropyl-3-(methylsulfonyl)prop-2-en-1- amine (34 mg, 0.194 mmol) in DMF (2 mL) was added AcOH (35 mg, 0.58 mmol). The mixture was stirred at 110°C for 2 h. TLC and LCMS showed the reaction was completed. The mixture was cooled to rt and diluted with water (10 mL), extracted with EtOAc (5 mL x 3). The combined organic layers were washed by brine (10 mL), dried over Na2SO4, filtered, the filtrate was concentrated under vacuum. The residue was purified by Prep-TLC andP383145WO June 2025 95 Prep-SFC (mobile phase CO2 / methanol(10% MeCN) (65 / 35) to obtain the desired products Example 13 (13 mg, 15% yield) and Example 13b (13 mg, 15% yield) as white solids. Assignment of chirality as R and S, respectively, is made arbitrarily based on order of elution in UPCC. Example 13 6‐[(1R,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐ difluoroethyl)‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one1H NMR (400 MHz, DMSO-d6) δ 9.68 (s, 1H), 8.33 (s, 1H), 7.71-7.68 (m, 2H), 7.52-7.40 (m, 3H), 7.08-6.94 (m, 2H), 4.83-4.79 (m, 1H), 3.03 (s, 3H), 2.03 (t, J = 19.2 Hz, 3H), 1.85-1.82 (m, 1H), 0.82-0.80 (m, 1H), 0.72-0.68 (m, 1H), 0.60-0.58 (m, 1H), 0.41-0.37 (m, 1H). UPLC (Waters-Base): Rt: 4.08 min; 100% purity. LC-MS (Agilent-Acid): Rt: 2.10 min; m / z: [M+H]+ 446.1. UPCC Rt: 1.652 min (Mobile phase CO2 / methanol (65 / 35) Example 13b 6‐[(1S,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐ difluoroethyl)‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one1H NMR (400 MHz, DMSO-d6) δ 9.68 (s, 1H), 8.33 (s, 1H), 7.71-7.68 (m, 2H), 7.52-7.40 (m, 3H), 7.08-6.94 (m, 2H), 4.83-4.79 (m, 1H), 3.03 (s, 3H), 2.03 (t, J = 19.2 Hz, 3H), 1.85-1.82 (m, 1H), 0.82-0.80 (m, 1H), 0.72-0.68 (m, 1H), 0.60-0.58 (m, 1H), 0.41-0.37 (m, 1H). UPLC (Waters-Base): Rt: 4.08 min; 99.4% purity. LC-MS (Agilent-Acid): Rt: 2.10 min; m / z: [M+H]+ 446.1. UPCC Rt: 2.175 min (Mobile phase CO2 / methanol (65 / 35).P383145WO June 2025 96 Example 14 - Synthesis of 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐ methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐one Ethyl 3-oxo-4-(o-tolyl)butanoateA solution of 2-(o-tolyl)-acetic acid (2.0 g, 13.3 mmol) and CDI (2.8 g, 17.3 mmol) in THF (30 mL) was stirred at room temperature for 40 minutes. Malonic acid monoethyl ester potassium salt (2.7 g, 16.0 mmol) and MgCl2 (1.5 g, 16.0 mmol) was added to the reaction and the mixture was stirred at 60°C for 6h.1N HCl (30 mL) was added and the solution was extracted with ethyl acetate (50 mL x 3). The combined organic layers were washed with brine (100 mL), dried over Na2SO4, filtered and the filtrate was concentrated in vacuo. The residue was purified by column chromatography (petroleum ether / ethyl acetate 90 / 10, v / v) to obtain the desired product (1.3 g, 44.3 % yield) as a colourless oil.1H NMR (400 MHz, CDCl3) δ 7.17 – 7.01 (m, 4H), 4.10 (q, J = 7.2 Hz, 2H), 3.77 (s, 2H), 3.36 (s, 2H), 2.18 (s, 3H), 1.19 (t, J = 7.1 Hz, 4H). Ethyl 2-(ethoxymethylene)-3-oxo-4-(o-tolyl)butanoateA mixture of ethyl 3-oxo-4-(o-tolyl)butanoate (2.5 g, 11.36 mmol) and triethoxymethane (5 g, 34.1 mmol) and Ac2O (1.85 g, 18.18 mmol) was stirred at 100°C for 4 hours. The mixture was cooled to rt and diluted with water (10 mL) and extracted with EtOAc (30 mL x 3). The combined organic layers were washed with brine (20 mL), dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by column chromatography on silica gel eluted with petroleum ether / ethyl acetate (90 / 10, v / v) to give the desired product (600 mg, 19% yield) as a colourless oil.P383145WO June 2025 97 Ethyl 2-(tert-butyl)-4-(2-methylbenzyl)pyrimidine-5-carboxylateTo a mixture of ethyl 2-(ethoxymethylene)-3-oxo-4-(o-tolyl)butanoate (300 mg, 1.1 mmol) and pivalimidamide (110 mg, 1.1 mmol) in EtOH (4 mL) was added Na2CO3 (300 mg, 2.72 mmol) at rt. The mixture was stirred at 90°C for 2 hours then cooled to rt and concentrated under vacuum. The residue was purified by column chromatography on silica gel eluted with petroleum ether / ethyl acetate (85 / 15, v / v) to give the desired product (300 mg, 88% yield) as a colourless oil. LCMS (Agilent-Acid): Rt: 2.51 min; m / z [M+1]+ 313.2 Ethyl (E)-2-(tert-butyl)-4-(2-(dimethylamino)-1-(o-tolyl)vinyl)pyrimidine-5-carboxylateTo a mixture of ethyl 2-(tert-butyl)-4-(2-methylbenzyl)pyrimidine-5-carboxylate (200 mg, 0.64 mmol) in DMF (4 mL) was added DMF-DMA (229 mg, 1.92 mmol) at rt. The mixture was stirred at 110°C for 2 hours then cooled to rt and diluted with water (20 mL) and extracted with EtOAc (10 mL x 3). The combined organic layers were washed with brine (20 mL), dried over Na2SO4, filtered and concentrated to give the crude product (160 mg crude). The crude product was used in the next step without further purification. LCMS (Agilent-Acid): Rt: 1.94 min; m / z [M+1]+ 368.2 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐methylphenyl)pyrido[4,3‐ d]pyrimidin‐5‐oneP383145WO June 2025 98 A mixture of ethyl (E)-2-(tert-butyl)-4-(2-(dimethylamino)-1-(o-tolyl)vinyl)pyrimidine-5- carboxylate (160 mg crude, 0.44 mmol) and (E)-3-(methylsulfonyl)prop-2-en-1-amine TFA salt (45.6 mg, 0.50 mmol) in AcOH (3mL) was stirred at 110°C for 2h. TLC and LCMS showed the reaction was completed. The solution pH was adjusted to ~9 by saturated NaHCO3 (100 mL), and was extracted with EtOAc (30 mL x3) .The combined organic layer was concentrated in vacuo and the residue purified by column chromatography (petroleum ether / ethyl acetate 50 / 50, v / v) to obtain the desired product (12 mg, 6.7% yield) as a white solid.1H NMR (400 MHz, DMSO) δ 9.52 (s, 1H), 7.92 (s, 1H), 7.40 – 7.19 (m, 4H), 7.03 – 6.88 (m, 1H), 6.76 (d, J = 15.4 Hz, 1H), 4.97 – 4.80 (m, 2H), 2.98 (s, 3H), 2.15 (s, 3H), 1.28 (s, 9H). UPLC (Waters-Acid): Rt:4.34 min; 254 nm: 97.3 % of purity; 214 nm: 97.2 % purity. LC-MS (Agilent-Acid): Rt:2.17 min; m / z: [M+H] + 412.2. Example 15 – Synthesis of 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐ methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐oneTo a mixture of ethyl (E)-2-(tert-butyl)-4-(2-(dimethylamino)-1-(o-tolyl)vinyl)pyrimidine-5- carboxylate (240 mg crude, 0.64 mmol) and (R,E)-1-cyclopropyl-3-(methylsulfonyl)prop-2- en-1-amine (112 mg, 0.64 mmol) in DMF (3 mL) was added AcOH (115 mg, 1.92 mmol) at rt. The mixture was stirred at 110°C for 1 hour. The mixture was cooled to rt and diluted with water (15 mL) and extracted with EtOAc (10 mL x 3). The combined organic layers were washed with brine (20 mL), dried over Na2SO4, filtered and concentrated. The residue was purified by Prep-TLC eluted with petroleum ether / ethyl acetate (1 / 1) to give the desired product (40 mg, 13.5% yield) as a white solid.1HNMR (400 MHz, DMSO-d6) δ 9.52 (s, 1H), 8.05 (s, 1H), 7.33-7.25 (m, 4H), 7.04-6.99 (m, 1H), 6.93-6.89 (m, 1H), 4.82-4.78 (m, 1H), 3.02 (s, 3H), 2.17 (s, 3H), 1.78-1.71 (m, 1H), 1.27 (s, 9H), 0.79-0.76 (m, 1H), 0.69-0.66 (m, 1H), 0.59-0.53 (m, 1H), 0.38-0.34 (m, 1H). LCMS (Agilent-Acid): Rt: 2.28 min; m / z [M+1]+ = 452.1P383145WO June 2025 99 Example 15b - Synthesis of 2‐tert‐butyl‐6‐[(1S,2E)‐1‐cyclopropyl‐3‐ methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐oneBiological Assay 1 A functional WRN DNA strand displacement assay was used to evaluate inhibitors of WRN helicase activity.^Experiments were performed using a truncated WRN protein containing the helicase activity (aa 500-946), ATP and a DNA duplex substrate (E1: 5’- TTTTTTTTTTTTTTTTTTTTTTTTTTTTTTCGTACCCGATGTGTTCGTAC-3’, SEQ ID NO: 1; E2: 5’- GCACGAACACATCGGGTACGTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT-3’, SEQ ID NO: 2) in the assay buffer (25 mM Tris-HCl (pH 7.8), 0.01% BSA, 0.01% Tween 20, 2 mM MgCl2, 50 mM NaCl, 1 mM DTT). E1 and E2 are respectively tagged with a BHQ2 fluorescence quencher (3’ end) and a cy3 fluorochrome (5’ end) (custom synthesis ATDBio Ltd, UK).5 µL of assay buffer containing WRN protein (0.8 nM, 2-fold working concentration) was transferred into assay ready plates, containing 0.1 µL of compounds dissolved in DMSO and left to incubate for 30 min at 23°C. Reaction was then triggered by addition of 5 µL of WRN buffer containing DNA substrate (10 nM, 2-fold working concentration) and ATP (4 mM, 2-fold working concentration) and plates were incubated at 23°C for 25 min. Reaction was stopped using 5 µL of STOP buffer (40 mM Tris-HCl (pH 8.8), 20 mM EDTA, 6 nM Proteinase K) and fluorescence was measured after 20 min, using Tecan F200 infinite plate reader (excitation / emission – 535 / 590nM). The reported IC50 values shown in Table A below are the geometric means of at least 2 independent replicates. Biological Assay 2 In an adaptation to Biological Assay 1 the incubation time is increased to 270 min at 23°C prior to initiating the reaction by addition of WRN buffer containing DNA substrate and ATP. All other assay details are as described for Biological Assay 1.P383145WO June 2025 100 Table A - WRN*** denotes an IC50 of less than 10^M ** denotes an IC50 of 10^M to 50^M * denotes an IC50 of greater than 50^M Biological Assay 3 WRN protein (hWRN(517-1238) was diluted in Assay buffer (25 mM Tris-HCl, 5 mM NaCl, 2 mM MgCl2, 0.01% Tween-20 ,1 mM TCEP, 2.5 μg / mL Calf thymus DNA, pH 8.0) with 0.2 mM ATP and plated in assay plate, 5 μL / well. These solutions of WRN (at final concentration of 5 nM) and ATP were preincubated with serial dilutions of test compounds dissolved in DMSO (final DMSO concentration is 1%). for 4 hours at room temperature. The mixture was briefly centrifuged at 1000 rpm for 1 minute. Following preincubation, enzymatic reactionP383145WO June 2025 101 was initiated by addition of a 5 μL / well ATP (final concentration is 4 mM), 5 μL / well the capturing strand (5’-GAACGAACACATCGGGTACG-3’, SEQ ID NO: 3, final concentration is 1 μM) and the ds DNA (5’- Cy5 / GAACGAACACATCGGGTACGTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT-3’, SEQ ID NO: 4; 5’-TTTTTTTTTTTTTTTTTTTTTTTTTTTTTTCGTACCCGATGTGTTCGTTC / BHQ2- 3’, SEQ ID NO: 5; final concentration is 100 nM). The mixture was centrifuged at 1000 rpm for 1 minute. The reaction was allowed to continue for 30 minutes at room temperature followed by endpoint measurement of fluorescence (Ex.620 nm, Em 685 nm) on a BMG. WRN activity was normalized to signal from wells without WRN protein (Low control, 100% inhibition) and wells with protein treated only with DMSO (High control, 0% inhibition). For each compound the potency of inhibition (IC50) was determined using Graphpad Prism or XLfit. Biological Assay 4 In an adaptation to Biological Assay 3 the preincubation conditions excluded the presence of ATP in the assay buffer. All other assay details are as described for Biological Assay 3. Table B - WRNP383145WO June 2025 102*** denotes an IC50 of less than 1 ^M ** denotes an IC50 of 1 ^M to 30 ^M * denotes an IC50 of greater than 30 ^M

Claims

P383145WO June 2025 103 CLAIMS 1. A compound, or pharmaceutically acceptable salt thereof, having the structural formula I shown below:wherein: RS is (1-3C)alkyl; R1 is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a (1-6C)alkyl, -[CH2]m-(3- 6C)cycloalkyl, -[CH2]m-heterocyclyl group, -[CH2]m-aryl group or -[CH2]m-heteroaryl group, wherein integer m is 0, 1, 2 or 3; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; X is selected from N or CRx; wherein: Rxis selected from hydrogen, halo, (1-2C)alkyl, (1-2C)alkoxy or NH2; R2is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-4C)alkylene, (2-4C)alkenylene or (2-4C)alkynylene;P383145WO June 2025 104 X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -N(R100b)-C(O)-NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where each R100aand R100bgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n-(3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-aryl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; R3is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-4C)alkylene, (2-4C)alkenylene or (2-4C)alkynylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, -NR100c-, -N(R100d)-C(O)-NR100c-, -SO2N(R100c)- or -N(R100c)SO2-, where each R100cand R100dgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-heterocyclyl, -[CH2]p-aryl, or -[CH2]p-heteroaryl group, wherein integer p is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein:P383145WO June 2025 105 L4is absent or (1-4C)alkylene, (2-4C)alkenylene or (2-4C)alkynylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100e)-, -N(R100e)-C(O)-, -NR100e-, -N(R100f)-C(O)-NR100e-, -SO2N(R100e)- or -N(R100e)SO2-, where each R100eor R100fgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-heterocyclyl, -[CH2]q-aryl, or -[CH2]q-heteroaryl group, wherein integer q is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy.

2. A compound according to claim 1, wherein RSis methyl.

3. A compound according to claim 1 or claim 2, wherein R1is selected from hydrogen, or a group: -Q wherein Q is selected from the group consisting of a (1-6C)alkyl, -[CH2]m-(3-6C)cycloalkyl, - [CH2]m-[4 to 8 membered heterocyclyl], -[CH2]m-phenyl, or a -[CH2]m-[5- or 6-membered heteroaryl] group, wherein integer m is 0, 1, 2 or 3; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1-2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy.

4. A compound according to any one of claims 1 to 3, wherein R1 is selected from hydrogen, or a group: -Q whereinP383145WO June 2025 106 Q is selected from the group consisting of a (1-6C)alkyl, -[CH2]m-(3-6C)cycloalkyl or -[CH2]m-phenyl group, wherein integer m is 0, 1 or 2; and any cycloalkyl or phenyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1- 2C)alkyl, (1-2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy.

5. A compound according to any one of claims 1 to 4, wherein R1is selected from hydrogen, or a group: -Q wherein Q is -[CH2]m-(3-4C)cycloalkyl, wherein integer m is 0 or 1; and the cycloalkyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, (1-2C)alkyl or (1-2C)alkoxy; 6. A compound according to any one of claims 1 to 5, wherein R1is selected from hydrogen or cyclopropyl.

7. A compound according to any one of claims 1 to 6, wherein R2 is selected from one of the following options: (i) R2 is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene, (2-3C)alkenylene or (2-3C)alkynylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -N(R100b)-C(O)-NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where each R100aand R100bgroup present is independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-aryl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, aryl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituentsP383145WO June 2025 107 selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1-3C)alkoxy, (1- 3C)haloalkyl or (1-3C)haloalkoxy; (ii) R2 is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100a)-, -N(R100a)-C(O)-, -NR100a-, -SO2N(R100a)- or -N(R100a)SO2-, where R100ais independently selected from hydrogen or (1-2C)alkyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]n- (3-6C)cycloalkyl, -[CH2]n-heterocyclyl, -[CH2]n-phenyl, or -[CH2]n-heteroaryl group, wherein integer n is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-3C)alkyl, (1- 3C)alkoxy, (1-3C)haloalkyl or (1-3C)haloalkoxy; or (iii) R2 is selected from halo, cyano or a group: -L2-X2-Q2wherein: L2is absent or (1-3C)alkylene; X2is absent or is selected from the group consisting of -O- or -NR100a-, where R100ais independently selected from hydrogen or methyl; and Q2is selected from the group consisting of hydrogen, or a (1-6C)alkyl or (3- 6C)cycloalkyl group, wherein integer n is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1-2C)alkoxy. 8.. A compound according to any one of claims 1 to 7, wherein R2 is selected from one of the following options:P383145WO June 2025 1089. A compound according to any one of claims 1 to 8, wherein R3 is selected from one of the following options: (i) R3 is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent or (1-3C)alkylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, -NR100c-, -SO2N(R100c)- or -N(R100c)SO2-, where R100cis selected from hydrogen or (1- 2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-heterocyclyl, -[CH2]p-phenyl, or -[CH2]p-heteroaryl group, wherein integer p is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (ii) R3is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3P383145WO June 2025 109 wherein: L3is absent or (1-2C)alkylene; X3is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-N(R100c)-, -N(R100c)-C(O)-, or -NR100c-, where R100cis selected from hydrogen or (1-2C)alkyl; and Q3is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]p-(3-6C)cycloalkyl, -[CH2]p-[4- to 8-membered]heterocyclyl, -[CH2]p- phenyl, or -[CH2]p-[5- or 6-membered heteroaryl] group, wherein integer p is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (iii) R3is selected from hydrogen, halo, cyano or a group: -L3-X3-Q3wherein: L3is absent; X3is absent; and Q3is selected from the group consisting of a -[CH2]p-phenyl, or -[CH2]p-[5- or 6- membered heteroaryl] group, wherein integer p is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (iv) R3 is selected from hydrogen or phenyl optionally substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1-2C)alkoxy; or (v) R3 is selected from hydrogen or phenyl optionally substituted (1-2C)alkyl.

10. A compound according to any one of claims 1 to 9, wherein R4 is selected from one of the following options: (i) R4 is selected from hydrogen, halo, cyano or a group:P383145WO June 2025 110 -L4-X4-Q4wherein: L4is absent or (1-3C)alkylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)-O-, -O-C(O)-, -S(O)0-2-, -C(O)-N(R100e)-, -N(R100e)-C(O)-, -NR100e-, -SO2N(R100e)- or -N(R100e)SO2-, where R100eis selected from hydrogen or (1- 2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-heterocyclyl group, -[CH2]q-phenyl group, or -[CH2]q-heteroaryl group, wherein integer q is 0, 1, 2, 3 or 4; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl, (1- 2C)alkoxy, (1-2C)haloalkyl or (1-2C)haloalkoxy; (ii) R4is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein: L4is absent or (1-2C)alkylene; X4is absent or is selected from the group consisting of -O-, -C(O)-, -C(O)- N(R100e)-, -N(R100e)-C(O)-, or -NR100e-, where R100eis selected from hydrogen or (1-2C)alkyl; and Q4is selected from the group consisting of hydrogen, or a (1-6C)alkyl, -[CH2]q-(3-6C)cycloalkyl, -[CH2]q-[4- to 8-membered heterocyclyl], -[CH2]q- phenyl, or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (iii) R4 is selected from hydrogen, halo, cyano or a group: -L4-X4-Q4wherein:P383145WO June 2025 111 L4is absent or (1-2C)alkylene; X4is absent; and Q4is selected from the group consisting of a (1-6C)alkyl, -[CH2]q-(3- 6C)cycloalkyl, -[CH2]q-[4- to 6-membered heterocyclyl], -[CH2]q-phenyl or -[CH2]q-[5- or 6-membered heteroaryl] group, wherein integer q is 0, 1 or 2; and any alkyl, cycloalkyl, phenyl, heteroaryl or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; (iv) R4is selected from hydrogen or a group: -L4-X4-Q4wherein: L4is absent or (1C)alkylene; X4is absent; and Q4is selected from the group consisting of a (1-6C)alkyl, (3-6C)cycloalkyl, 4- to 6-membered heterocyclyl, or phenyl, wherein any alkyl, cycloalkyl, phenyl, or heterocyclyl group is optionally further substituted with one or more substituents selected from: halo, hydroxy, cyano, amino, (1-2C)alkyl or (1- 2C)alkoxy; or (v) R4 is hydrogen.

11. A compound according to any one of claims 1 to 10, wherein X is selected from N or CH.

12. A compound according to claim 1, or a pharmaceutically acceptable salt thereof, wherein the compound has one of the structural formulae Ia to Io shown below:P383145WO June 2025 113wherein: RS is methyl; R1 is as defined in any one of claims 3 to 5; R2 is as defined in claim 6 or claim 7; R3is as defined in claim 8; R4is as defined in claim 9; and X is N or CH.

13. A compound selected from any one of the following: 6-(cyclopentoxy)-3-methyl-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one; 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-3-tetrahydropyran-4-yl-2,7-naphthyridin-1-one; 6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one; 3-benzyl-6-(cyclopentoxy)-2-[(E)-3-methylsulfonylallyl]-2,7-naphthyridin-1-one; 2-[(E,1S)-1-[(3-chlorophenyl)methyl]-3-methylsulfonyl-allyl]-6-(cyclopentoxy)-2,7- naphthyridin-1-one;P383145WO June 2025 114 2-[(E,1S)-1-[(3-chloro-4-hydroxy-phenyl)methyl]-3-methylsulfonyl-allyl]-6-(cyclopentoxy)-2,7- naphthyridin-1-one; 6-(cyclopentoxy)-2-[(E,1S)-1-[(4-hydroxy-3-methyl-phenyl)methyl]-3-methylsulfonyl-allyl]-2,7- naphthyridin-1-one; 2-tert-butyl-6-[(E)-3-methylsulfonylallyl]pyrido[4,3-d]pyrimidin-5-one; 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1S,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one; 2‐(1,1‐difluoroethyl)‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐phenylpyrido[4,3‐ d]pyrimidin‐5‐one; 6‐[(1R,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐difluoroethyl)‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one; 6‐[(1S,2E)‐1‐cyclopropyl‐3-methanesulfonylprop‐2‐en‐1‐yl]‐2‐(1,1‐difluoroethyl)‐8‐ phenylpyrido[4,3‐d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(2E)‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐methylphenyl)pyrido[4,3‐ d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1R,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐ methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐one; 2‐tert‐butyl‐6‐[(1S,2E)‐1‐cyclopropyl‐3‐methanesulfonylprop‐2‐en‐1‐yl]‐8‐(2‐ methylphenyl)pyrido[4,3‐d]pyrimidin‐5‐one; or a pharmaceutically acceptable salt thereof.

14. A pharmaceutical composition comprising a compound according to any one of claims 1 to 13, or a pharmaceutically acceptable salt thereof, and at least one pharmaceutically acceptable excipient.

15. A compound according to any one of claims 1 to 13, or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition according to claim 14, for use in:P383145WO June 2025 115 (i) therapy; (ii) the treatment of a disease characterized by overexpression of WRN; (iii) the treatment of cancer (iv) the treatment of a cancer having microsatellite instability (MSI); and / or (v) the treatment of lymphoma, rhabdoid tumor, multiple myeloma, uterine cancer, gastric cancer, peripheral nervous system cancer, rhabdomyosarcoma, bone cancer, colorectal cancer, mesothelioma, breast cancer, ovarian cancer, lung cancer, fibroblast cancer, central nervous system cancer, urinary tract cancer, upper aerodigestive cancer, leukemia, kidney cancer, skin cancer, esophageal cancer, and pancreatic cancer.

16. A method of: (i) treating a disease characterized by overexpression of WRN; (ii) treating cancer (iii) the treatment of a cancer having microsatellite instability (MSI); and / or (iv) treating lymphoma, rhabdoid tumor, multiple myeloma, uterine cancer, gastric cancer, peripheral nervous system cancer, rhabdomyosarcoma, bone cancer, colorectal cancer, mesothelioma, breast cancer, ovarian cancer, lung cancer, fibroblast cancer, central nervous system cancer, urinary tract cancer, upper aerodigestive cancer, leukemia, kidney cancer, skin cancer, esophageal cancer, and pancreatic cancer; the method comprising administered to patient in need of such treatment a therapeutically effective amount of a compound according to any one of claims 1 to 13, or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition according to claim 14.

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