Super-absorption cyanine dye and application thereof in biomedicine

Abstract

The invention provides a superabsorbent cyanine dye and application thereof in biomedicine, the chemical structure of the superabsorbent cyanine dye is as shown in formula I, and R1-R7 and Y-are as defined in the specification. The invention provides a novel superabsorption cyanine dye, and the absorption and emission wavelength of the novel superabsorption cyanine dye is close to 800 nm and even larger than 800 nm. The dye is high in absorption strength and good in stability, and can be used as a contrast agent to realize clinical application. # imgabs0 #

Description

Technical Field

[0001] The invention belongs to the field of organic dyes, and in particular relates to a super-absorption cyanine dye and its application in biomedicine. Background Art

[0002] With the widespread popularity of laparoscopic surgery and the rapid development of surgical robots, more accurate intraoperative positioning and identification are needed. Therefore, fluorescence-guided surgery has gradually been applied in clinical practice. Using specific fluorescent contrast agents (dyes), imaging can be performed during surgery, and blood vessels, tumors, lymph nodes, nerves and other parts can be identified in real time, breaking through the accuracy limits of traditional surgical treatments. This technology provides new tools for precise intraoperative target positioning and finding the best surgical path, minimizing intraoperative bleeding and iatrogenic nerve damage, and ensuring the safety of surgery.

[0003] Traditional fluorescent dyes absorb and emit wavelengths in the visible light region, with relatively few commercially available dyes in the near-infrared region (above 700 nm). Visible-light fluorescence imaging is subject to interference from light scattering, tissue penetration depth, biological background signals, and is phototoxic, making it unsuitable for long-term imaging of living biological samples. Near-infrared super-absorption fluorescent dyes can overcome these limitations, providing higher imaging signal-to-noise ratios, reducing dye usage, and improving safety, making them highly sought after in the field of fluorescence imaging.

[0004] Heptacyanine (Cy7) dye has high brightness and good biocompatibility and is one of the commonly used dyes for fluorescence imaging. Fluorescence-guided surgery based on indocyanine green (ICG) has been widely used in various medical fields, including cardiovascular, bile duct, ureteral, and gastrointestinal angiography. However, ICG still has inherent defects, such as photoinstability and easy aggregation leading to fluorescence quenching. Therefore, the field still needs to develop cyanine dyes with wavelengths close to or greater than 800nm, strong absorption, and high stability to achieve clinical application as contrast agents. Summary of the Invention

[0005] The purpose of the present invention is to provide a super-absorption cyanine dye and its application in biomedicine.

[0006] The first aspect of the present invention provides a compound of formula I having the structure shown below:

[0007]

[0008] In Formula I,

[0009] R1 and R2 are each independently selected from the group consisting of substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl, substituted or unsubstituted C1-C10 alkoxy, substituted or unsubstituted C1-C10 alkylthiol, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted 3-12 membered heterocyclyl, substituted or unsubstituted C6-C14 aryl, substituted or unsubstituted 5-14 membered heteroaryl and halogen; the C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C1 -C10 alkoxy, C1-C10 alkylthiol, C3-C12 cycloalkyl, 3-12 membered heterocyclyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 alkylthiol, C3-C12 cycloalkyl, 3-12 membered heterocyclyl, C6-C14 aryl, 5-14 membered heteroaryl and halogen; said 3-12 membered heterocyclyl and 5-14 membered heteroaryl containing 1, 2 or 3 heteroatoms selected from N, O and S;

[0010] Or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl group;

[0011] R3, R4, R5 and R6 are each independently selected from the group consisting of hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, halogen, hydroxy, amino, nitro and carboxyl;

[0012] Alternatively, R4, the carbon to which R4 is attached, R5, and the carbon to which R5 is attached together form a C4-C12 cycloalkyl group, which is optionally substituted with 1, 2, 3, 4, 5, or 6 substituents selected from C1-C10 alkyl, C1-C10 alkoxy, and halogen;

[0013] R7 is selected from the group consisting of: C1-C10 alkyl, C2-C10 alkenyl, and C2-C10 alkynyl;

[0014] Y - Selected from: 1 / 2 sulfate, chloride, fluoride, bromide, nitrate, 1 / 2 carbonate, bicarbonate, acetate, 1 / 2 oxalate and trifluoroacetate.

[0015] The second aspect of the present invention provides a fluorescent dye or a dye composition or a kit, which contains the compound of formula I described in the first aspect of the present invention and an optional solvent.

[0016] In one or more embodiments, the solvent is a buffer, preferably a PBS buffer.

[0017] In one or more embodiments, the compound of formula I is entrapped by a phospholipid derivative, preferably DSPE-mPEG2000.

[0018] The third aspect of the present invention provides a use of the compound of formula I described in the first aspect of the present invention in the preparation of a reagent used in cell fluorescence imaging or animal fluorescence imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a universal synthetic route for the super-absorption cyanine dyes of the present invention.

[0020] Figure 2 These are the absorption and emission spectra of compounds 8, 9, 14-18 and the control molecule M780 in dichloromethane.

[0021] Figure 3 These are the absorption and emission spectra of BSW-X series compounds and the reference molecule M780 in dichloromethane.

[0022] Figure 4 This is the fluorescence imaging of compound 14 on HeLa living cells.

[0023] Figure 5 Fluorescence imaging of mice was performed using compound 14 encapsulated by DSPE-mPEG2000. DETAILED DESCRIPTION

[0024] To facilitate understanding of the features and effects of the present invention by those skilled in the art, the following provides a general description and definition of the terms and expressions used in the specification and claims. Unless otherwise indicated, all technical and scientific terms used herein have the ordinary meanings as understood by those skilled in the art regarding the present invention. In the event of conflict, the definitions in this specification shall prevail.

[0025] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0026] Herein, “comprising,” “including,” “containing” and similar terms encompass the meanings of “consisting essentially of” and “consisting of,” for example, when “A comprises B and C” is disclosed herein, “A consists essentially of B and C” and “A consists of B and C” should be deemed to have been disclosed herein.

[0027] Throughout this document, all features, such as values, amounts, amounts, and concentrations, that are defined in numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered to encompass and specifically disclose all possible subranges and individual values ​​within those ranges (including integers and fractions). For example, "containing 1 to 6 carbon atoms" would include containing 1 to 6 carbon atoms, containing 2 to 6 carbon atoms, containing 4 carbon atoms, and so on.

[0028] In this document, unless otherwise specified, percentage refers to mass percentage and ratio refers to mass ratio.

[0029] Herein, when describing embodiments or examples, it should be understood that they are not intended to limit the present invention to these embodiments or examples. On the contrary, all alternatives, modifications and equivalents of the methods and materials described herein are encompassed within the scope defined by the claims.

[0030] In this document, for the sake of brevity, not all possible combinations of the various technical features in each embodiment or example are described. Therefore, as long as there are no contradictions in the combination of these technical features, the various technical features in each embodiment or example can be combined in any way, and all possible combinations should be considered to be within the scope of this specification.

[0031] Certain chemical groups defined herein are preceded by a simplified notation to indicate the total number of carbon atoms present in the group. For example, a C1-C4 alkyl group refers to an alkyl group as defined below having a total of 1 to 4 carbon atoms. The total number of carbon atoms in the simplified notation does not include carbons that may be present in substituents of the group.

[0032] As used herein, "halo" or "halogen" refers to an element of Group 17 with an atomic number of 9 to 85. "Halogen" or "halogen atom" refers to F, Cl, Br, and I. "Halogenated" means substituted with an atom selected from F, Cl, Br, and I. "Halide anion" refers to an anion formed when a halogen atom gains an electron, including Cl — Br — , I — 、F — .

[0033] As used herein, "hydroxy" refers to -OH.

[0034] As used herein, "amino" refers to -NH2.

[0035] As used herein, "nitro" refers to -NO2.

[0036] As used herein, "carboxyl" refers to -COOH.

[0037] As used herein, "sulfate" refers to SO4 2- .

[0038] As used herein, "nitrate" refers to NO3 - .

[0039] As used herein, "carbonate" refers to CO3 - .

[0040] As used herein, "bicarbonate" refers to HCO3 - .

[0041] As used herein, "acetate" refers to CH3COO - .

[0042] As used herein, "oxalate" refers to C2O4 2- .

[0043] As used herein, "trifluoroacetate" refers to CF3COO - .

[0044] As used herein, "alkyl" refers to a straight or branched monovalent saturated hydrocarbon radical having a specified number of carbon atoms. Specific alkyl groups are those having 1 to 10 carbon atoms ("C1-C10 alkyl"), typically containing 1 to 8 carbon atoms (C1-C8 alkyl), preferably containing 1 to 6 carbon atoms (C1-C6 alkyl), and more preferably containing 1 to 4 carbon atoms (C1-C4 alkyl). Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, and the like.

[0045] As used herein, as a group or part of other groups, the term "alkenyl" refers to a straight or branched hydrocarbon chain group consisting only of carbon atoms and hydrogen atoms, containing at least one double bond, connected to the rest of the molecule by a single bond. In some embodiments, the alkenyl group contains 2 to 10 carbon atoms ("C2-C10 alkenyl"), preferably contains 2 to 8 carbon atoms ("C2-C8 alkenyl"), and more preferably contains 2 to 6 carbon atoms ("C2-C6 alkenyl"). Non-limiting examples of alkenyl groups include, but are not limited to, vinyl, propenyl, allyl, butenyl, but-1-enyl, but-2-enyl, pentenyl, pent-1-enyl, pentadienyl, penta-1,4-dienyl, etc. Unless otherwise specifically provided in this specification, alkenyl groups may be optionally substituted.

[0046] As used herein, the term "alkynyl" as a group or part of another group refers to a straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms with one or more carbon-carbon triple bonds (-C≡C-) connected to the rest of the molecule by a single bond. In some embodiments, the alkynyl group contains 2-10 carbon atoms ("C2-C10 alkynyl"), preferably contains 2 to 8 carbon atoms ("C2-C8 alkynyl"), and more preferably contains 2 to 6 carbon atoms ("C2-C6 alkynyl"). Non-limiting examples of alkynyl groups include ethynyl, 1-propynyl, 1-methyl-2-propynyl, 2-propynyl, 1-butynyl, and 2-butynyl, etc. Unless otherwise specifically provided in this specification, the alkynyl group may be optionally substituted.

[0047] As used herein, "aryl" refers to an unsaturated aromatic carbocyclic group having a single ring (e.g., phenyl) or multiple fused rings (e.g., naphthyl or anthracenyl), wherein the fused rings may or may not be aromatic. In one variation, the aryl group comprises 6 to 14 ring carbon atoms, preferably a C6-C10 aryl group. The aryl group having more than one ring and at least one of which is a non-aromatic ring can be attached to the parent structure at the aromatic ring position or at the non-aromatic ring position. In one variation, the aryl group having more than one ring and at least one of which is a non-aromatic ring is attached to the parent structure at the aromatic ring position. The example of an aryl group includes phenyl, naphthyl, phenanthrenyl, anthracenyl, indenyl, azulenyl, biphenyl, biphenylene and fluorenyl.

[0048] As used herein, "alkoxy" refers to alkyl-O-, and preferred alkoxy is C1-C10 alkoxy, such as C1-C8 alkoxy, C1-C6 alkoxy, C1-C4 alkoxy, which includes, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexyloxy, 1,2-dimethylbutoxy and the like.

[0049] As used herein, "alkylmercapto" refers to a group in which the hydrogen of the mercapto group is replaced by an alkyl group as described above, i.e., R'S-, wherein R' is an alkyl group. In some embodiments, the alkylmercapto group may be a mercapto group substituted by a C1-C10 alkyl group (C1-C10 alkylmercapto group), a mercapto group substituted by a C1-C8 alkyl group (C1-C8 alkylmercapto group), a mercapto group substituted by a C1-C6 alkyl group (C1-C6 alkylmercapto group), and a mercapto group substituted by a C1-C4 alkyl group (C1-C4 alkylmercapto group).

[0050] As used herein, "cycloalkyl" or "carbocyclyl" refers to a saturated cyclic hydrocarbon with 3 to 12 ring carbon atoms, comprising one ring such as cyclohexyl or multiple rings such as adamantyl. The cycloalkyl comprising more than one ring can be fused, spirocyclic or bridged or a combination thereof. Preferred cycloalkyls are saturated cyclic hydrocarbons with 3 to 8 ring carbon atoms ("C3-C8 cycloalkyl"). In some embodiments, the cycloalkyl group has 5 to 10 ring carbon atoms ("C5-C10 cycloalkyl"). In some embodiments, the cycloalkyl group has 7 to 12 ring carbon atoms ("C7-C12 cycloalkyl"). Examples of cycloalkyls include adamantyl, decahydronaphthyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cycloheptyl etc.

[0051] As used herein, as a group or part of other groups, the term "spirocyclyl" or "spiro ring" refers to a ring system consisting of multiple (e.g., two, three or more) rings, wherein at least two rings are cycloalkyl rings that are combined with each other to share a common carbon atom. In some embodiments, the spirocyclyl contains 6 to 12 ring carbon atoms, 6 to 11 ring carbon atoms, 6 to 10 ring carbon atoms, 6 to 9 ring carbon atoms, 6 to 8 ring carbon atoms, 6 to 7 ring carbon atoms. Non-limiting examples of spirocyclyl include, but are not limited to, spiro [5.5] undecyl, spiro-pentadienyl, spiro [3.6] decyl, etc. Unless otherwise specifically provided in this specification, spirocyclyl may be optionally substituted.

[0052] As used herein, the term "paracyclyl" or "paracyclyl (also known as "fused ring"), as a group or as part of another group, refers to a cycloalkyl ring system consisting of multiple (e.g., two, three, or more) rings, at least two of which are cycloalkyl rings joined to each other by sharing two adjacent carbon atoms (i.e., the at least two rings share a covalent bond such that the bridgehead atoms are directly connected). In some embodiments, the paracyclyl group contains 5 to 12 ring carbon atoms, 5 to 11 ring carbon atoms, 5 to 10 ring carbon atoms, 5 to 9 ring carbon atoms, 5 to 8 ring carbon atoms, 5 to 7 ring carbon atoms, or 5 to 6 ring carbon atoms. Non-limiting examples of cyclyl groups include, but are not limited to, 2,3-dihydroindanyl, 1,2,3,4-tetrahydro-naphthyl, 5,6,7,8-tetrahydro-naphthyl, 8,9-dihydro-7H-benzocyclohepten-6-yl, 6,7,8,9-tetrahydro-5H-benzocycloheptenyl, 5,6,7,8,9,10-hexahydro-benzocyclooctenyl, etc. Unless stated otherwise specifically in the specification, cyclyl groups may be optionally substituted.

[0053] As used herein, the term "bridged ring group" or "bridged ring" as a group or part of another group refers to a ring system consisting of multiple (e.g., two, three, or more) rings, wherein at least two of the rings are cycloalkyl groups that are connected to each other by sharing three or more carbon atoms (the at least two rings are separated by a bridge containing at least one atom between the two bridgehead atoms). In some embodiments, the bridged ring group contains 8 to 12 ring carbon atoms, 8 to 11 ring carbon atoms, 8 to 10 ring carbon atoms, or 8 to 9 ring carbon atoms. Non-limiting examples of bridged ring groups include, but are not limited to, bicyclo[1.1.1]pentenyl, bicyclo[2.2.1]heptenyl, bicyclo[2.2.1]heptyl, bicyclo[3.1.1]heptyl, bicyclo[2.2.2]octyl, bicyclo[3.2.1]octyl, bicyclo[3.2.1]octenyl, bicyclo[3.3.1]nonyl, bicyclo[3.3.3]undecyl, adamantyl, and the like. Unless stated otherwise specifically in the specification, a bridged ring group may be optionally substituted.

[0054] As used herein, the term "heterocyclyl" or "heterocycle" as a group or part of another group refers to a stable saturated or partially unsaturated 3- to 12-membered non-aromatic cyclic group or moiety consisting of 2 to 11 carbon atoms (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 carbon atoms) and 1 to 5 heteroatoms (e.g., 1, 2, 3, 4, or 5 heteroatoms) selected from nitrogen, phosphorus, oxygen, and sulfur. Unless otherwise specified in the specification, the heterocyclyl group can be a monocyclic, bicyclic, tricyclic, or multicyclic ring system, which may include a fused / paracyclic system (i.e., paracyclic heterocyclyl, such as a 4-9-membered paracyclic heterocyclyl), a bridged ring system (i.e., a bridged heterocyclyl, such as a 6-12-membered bridged heterocyclyl), or a spirocyclic system (i.e., a spiroheterocyclyl, such as a 6-12-membered spiroheterocyclyl). A cyclic heterocyclic group refers to a ring system of a heterocyclic group consisting of multiple (e.g., two, three, or more) rings, wherein at least two of the rings are bound to each other by sharing two adjacent atoms (i.e., the at least two rings share a covalent bond, such that the bridgehead atoms are directly connected). In some embodiments, the heterocyclic group is a bicyclic cyclic heterocyclic group. A bridged heterocyclic group refers to a ring system of a heterocyclic group consisting of multiple (e.g., two, three, or more) rings, wherein at least two of the rings are bound to each other by sharing three or more atoms (the at least two rings are separated by a bridge containing at least one atom between the two bridgehead atoms). A spiroheterocyclic group refers to a ring system of a heterocyclic group consisting of multiple (e.g., two, three, or more) rings, wherein at least two of the rings are bound to each other by sharing one carbon atom. The nitrogen, carbon, or sulfur atoms in the heterocyclic group may be optionally oxidized; the nitrogen atom may be optionally quaternized; and the heterocyclic group may be partially or fully saturated. The heterocyclic group may be connected to the rest of the molecule via a carbon atom or a heteroatom and by a single bond. In some cases, the heterocyclic group can be carbon-linked, oxygen-linked, nitrogen-linked or sulfur-linked. Unless otherwise specifically provided in this specification, the heterocyclic group can be optionally substituted. Unless otherwise specifically provided in this specification, the heterocyclic group can be optionally substituted.

[0055] In some embodiments, the heterocyclyl group is a stable 3- to 12-membered, 4- to 11-membered, 5- to 12-membered, 6- to 10-membered, 4- to 10-membered, 4- to 9-membered, or 3- to 8-membered non-aromatic monocyclic, bicyclic, bridged, or spirocyclic group containing 1 to 3 heteroatoms selected from nitrogen, oxygen, and sulfur. In some embodiments, the heterocyclyl group is a stable 3- to 10-membered (e.g., 3- to 8-membered, 5- to 10-membered, or 4- to 9-membered) non-aromatic monocyclic, bicyclic, tricyclic, or higher ring group (including fused, bridged, or spirocyclic groups) containing 1 to 3 heteroatoms selected from nitrogen, oxygen, and sulfur. Non-limiting examples of heterocyclyl groups include, but are not limited to, pyrrolidinyl, morpholinyl, piperazinyl, homopiperazinyl, piperidinyl, thiomorpholinyl, 2,7-diaza-spiro[3.5]nonan-7-yl, 2-oxa-6-aza-spiro[3.3]heptane-6-yl, 2-oxa-6-aza-spiro[3.4]octan-7-yl, 8-oxa-2-aza-spiro[4.5]decane-6-yl, 2,5-diaza-bicyclo[2.2.1]heptane-2-yl, azetidinyl, oxetanyl, thietanyl, thio heterocyclopentyl, pyranyl, tetrahydropyranyl, thiopyranyl, tetrahydrofuranyl, oxazinyl, dioxolane, tetrahydroisoquinolinyl, decahydroisoquinolinyl, imidazolinyl, imidazolidinyl, quinolizinyl, thiazolidinyl, isothiazolidinyl, isoxazolidinyl, dihydroindole, octahydroindole, octahydroisoindole, pyrrolidinyl, pyrazolidinyl, phthalimido, dioxothiomorpholinyl, dioxothiolane, dioxothietane, thiohexyl, dioxothiocyclohexyl, thiomorpholinyl, 1,4-oxathiohexyl, and the like.

[0056] As used herein, as a group or part of another group, the term "heteroaryl" or "heteroaromatic ring" refers to a conjugated ring system group or part having carbon atoms (e.g., 1 to 11 carbon atoms, 1 to 10 carbon atoms, such as 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 carbon atoms) and heteroatoms (e.g., 1 to 6 heteroatoms, such as 1, 2, 3, 4 or 5 heteroatoms) selected from nitrogen, oxygen and sulfur in the ring. In some embodiments, the heteroaryl group may contain 5 to 12 ring atoms, 5 to 10 ring carbon atoms, 5 to 8 ring atoms, 5 to 7 ring atoms, or 5 to 6 ring atoms. Unless otherwise specified in this specification, the heteroaryl group may be a monocyclic, bicyclic, tricyclic or more ring system, and may also be fused to an aryl or heterocyclic group as defined above. Examples of heteroaryl fused to aryl include, but are not limited to, benzopyridyl, benzopyrazolyl, benzimidazolyl, benzopyrrolyl, etc. The nitrogen, carbon or sulfur atom in the heteroaryl group may be optionally oxidized; the nitrogen atom may be optionally quaternized. For the purposes of this disclosure, in some embodiments, the heteroaryl group is a stable 5- to 12-membered aromatic group comprising 1 to 5 (e.g., 1, 2, 3, 4, or 5) heteroatoms selected from nitrogen, oxygen, and sulfur. In some embodiments, the heteroaryl group is a stable 5- to 10-membered aromatic group comprising 1 to 4 (e.g., 1, 2, 3, or 4) heteroatoms selected from nitrogen, oxygen, and sulfur, or a 5- to 6-membered aromatic group comprising 1, 2, or 3 heteroatoms selected from nitrogen, oxygen, and sulfur. Unless otherwise specifically provided in this specification, the heteroaryl group may be optionally substituted.

[0057] Non-limiting examples of heteroaryl groups include, but are not limited to, thienyl, imidazolyl, pyrazolyl, thiazolyl, oxazolyl, oxadiazolyl, isoxazolyl, pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, benzimidazolyl, benzopyrazolyl, indolyl, furanyl, pyrrolyl, triazolyl, tetrazolyl, triazinyl, indolizinyl, isoindolyl, indazolyl, isoindazolyl, purinyl, quinolyl, isoquinolyl, naphthazinyl, naphthyridinyl, quinoxalinyl, pteridinyl, carbazolyl, carbolinyl, phenanthridinyl, phenanthrolinyl, acridinyl, phenazinyl, isothiazolyl, benzothiazolyl, benzothiophenyl, oxatriol, oxazolyl, cinnolinyl, quinazolinyl, indolizinyl, o-phenanthroline, isoxazolyl, phenoxazinyl, phenothiazinyl, 4,5,6,7-tetrahydrobenzo[b]thienyl, naphthopyridinyl, [1,2,4]triazolo[4,3-b]pyridazinyl, [1,2,4]triazolo[4,3-a]pyrazinyl, [1,2,4]triazolo[4,3-c]pyrimidinyl, [1,2,4]triazolo[4,3-a]pyridinyl, imidazo[1,2-a]pyridinyl, imidazo[1,2-b]pyridazinyl, imidazo[1,2-a]pyrazinyl, etc.

[0058] As used herein, "optionally" or "optionally" means that the subsequently described event or circumstance may or may not occur, and the description includes both instances where the event or circumstance occurs and instances where it does not occur. For example, "optionally substituted aryl" means that the aryl group is substituted or unsubstituted, and the description includes both substituted aryl groups and unsubstituted aryl groups. The "optionally" substituents described in the claims and description of the present invention are selected from alkyl, alkenyl, alkynyl, alkoxy, alkylthiol, halogen, haloalkyl, haloalkenyl, haloalkynyl, hydroxy, nitro, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, and optionally substituted heterocyclyl.

[0059] As used herein, the term "substituted", whether or not preceded by the term "optionally" (i.e., equivalent to substituted or unsubstituted), refers to the replacement of one or more hydrogens of a specified group or portion by a "suitable substituent". Herein, the number of substituents may be one or more, i.e., 1, 2, 3, 4, 5, or 6 or more, depending on the group being substituted and the nature of the substituent. For example, when the substituent of an ethyl group is a halogen, the group may be substituted by 1, 2, 3, 4, or 5 substituents, such as trifluoroethyl, pentafluoroethyl, etc., depending on the structure of the substituted group. In some embodiments, the number of substituents is 1, 2, or 3. In some embodiments, the number of substituents is 1 or 2. In some embodiments, the number of substituents is 1. It will be understood that "substituted" or "substituted by..." includes implicit conditions, i.e., such replacement is carried out according to the allowed valence of the substituted atom, and the replacement produces a stable or chemically feasible compound, such as a compound that does not spontaneously transform, such as by rearrangement, cyclization, elimination, etc. Unless otherwise indicated, an "optionally substituted" group may have a suitable substituent at each substitutable position of the group, and when more than one position in any given structure may be substituted with more than one substituent selected from a specified group, the substituents may be the same or different at each position. It will be understood by those skilled in the art that the substituents themselves may be substituted if appropriate. Unless specifically indicated as "unsubstituted," reference to chemical moieties herein is understood to include substituted variants. For example, reference to an "aryl" group or moiety implicitly includes both unsubstituted aryl groups and substituted variants.

[0060] For the purpose of the present application as a whole, the “suitable substituents” mentioned above are understood to include, but are not limited to, the alkyl, alkenyl, alkynyl, halogen, haloalkyl, haloalkenyl, haloalkynyl, alkoxy, alkylthio, hydroxy, amino, monoalkylamino, dialkylamino, nitro, aryl, heteroaryl, cycloalkyl (e.g., cycloalkyl, cycloalkenyl, etc.), heterocyclyl, etc. described herein; these groups as substituents, including alkyl, alkenyl, alkynyl, alkyl in haloalkyl, alkenyl in haloalkenyl, alkynyl in haloalkynyl, alkoxy, alkyl in monoalkylamino, alkyl in dialkylamino, aryl, heteroaryl, cycloalkyl and heterocyclyl themselves are also optionally substituted, for example, they may be optionally substituted with one or more groups selected from alkyl, halogen, haloalkyl, alkoxy, hydroxy, amino, monoalkylamino, dialkylamino, nitro, aryl, heteroaryl, cycloalkyl and heterocyclyl.

[0061] Those skilled in the art will also appreciate that in the methods described herein, the functional groups of the intermediate compounds may need to be protected by appropriate protecting groups. Such functional groups include hydroxyl, amino, sulfhydryl, and carboxylic acid. Suitable hydroxyl protecting groups include trialkylsilyl or diarylalkylsilyl (e.g., tert-butyldimethylsilyl, tert-butyldiphenylsilyl, or trimethylsilyl), tetrahydropyranyl, benzyl, and the like. Suitable amino, amidino, and guanidino protecting groups include tert-butyloxycarbonyl, benzyloxycarbonyl, and the like. Suitable sulfhydryl protecting groups include -C(O)-R" (wherein R" is alkyl, aryl, or aralkyl), p-methoxybenzyl, trityl, and the like. Suitable carboxyl protecting groups include alkyl, aryl, or aralkyl esters.

[0062] Protecting groups can be introduced and removed according to standard techniques known to those skilled in the art and as described herein. The use of protecting groups is described in detail in Greene, TW and PGM Wuts, Protective Groups in OrganiSynthesis, (1999), 4th Ed., Wiley. Protecting groups can also be polymeric resins.

[0063] The present invention provides a compound of formula I having the structure shown below:

[0064]

[0065] In Formula 1:

[0066] R1 and R2 are each independently selected from the group consisting of substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl, substituted or unsubstituted C1-C10 alkoxy, substituted or unsubstituted C1-C10 alkylthiol, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted 3-12 membered heterocyclyl, substituted or unsubstituted C6-C14 aryl, substituted or unsubstituted 5-14 membered heteroaryl and halogen; the C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C1-C10 alkoxy, C1-C10 Alkylmercapto, C3-C12 cycloalkyl, 3-12 membered heterocyclyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 alkylmercapto, C3-C12 cycloalkyl, 3-12 membered heterocyclyl, C6-C14 aryl, 5-14 membered heteroaryl and halogen; the 3-12 membered heterocyclyl and 5-14 membered heteroaryl contain 1, 2 or 3 heteroatoms selected from N, O and S; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl;

[0067] R3, R4, R5 and R6 are each independently selected from the group consisting of hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, halogen, hydroxy, amino, nitro and carboxyl; or, R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C12 cycloalkyl, which is optionally substituted with 1, 2, 3, 4, 5 or 6 substituents selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy and halogen;

[0068] R7 is selected from the group consisting of: C1-C10 alkyl, C2-C10 alkenyl, and C2-C10 alkynyl;

[0069] Y - Selected from: 1 / 2 sulfate, chloride, fluoride, bromide, nitrate, 1 / 2 carbonate, bicarbonate, acetate, 1 / 2 oxalate and trifluoroacetate.

[0070] In some embodiments, R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl, substituted or unsubstituted C6-C14 aryl, substituted or unsubstituted 5-14 membered heteroaryl and halogen; the C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 alkylthiol, C6-C14 aryl, 5-14 membered heteroaryl and halogen; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl.

[0071] In some embodiments, R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C14 aryl and substituted or unsubstituted 5-14 membered heteroaryl; the C1-C10 alkyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 alkylthiol, C6-C14 aryl and 5-14 membered heteroaryl; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl.

[0072] In some embodiments, R1 and R2 are each independently selected from: C1-C10 alkyl optionally substituted with 1, 2, 3 or 4 C6-C14 aryl groups, and C6-C14 aryl optionally substituted with 1, 2, 3 or 4 substituents selected from C1-C10 alkyl, C1-C10 alkoxy and C1-C10 alkylthiol; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl group.

[0073] In some embodiments, R1 and R2 are each independently selected from: C1-C10 alkyl optionally substituted with 1 or 2 C6-C14 aryl groups, and C6-C14 aryl optionally substituted with 1 or 2 substituents selected from C1-C10 alkyl, C1-C10 alkoxy and C1-C10 alkylthiol; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl group.

[0074] In some embodiments, R1 and R2 are each independently selected from: C1-C6 alkyl optionally substituted with 1 or 2 C6-C10 aryl groups, and C6-C10 aryl optionally substituted with 1 or 2 substituents selected from C1-C6 alkyl, C1-C6 alkoxy and C1-C6 alkylthiol; or R1, R2 and the carbon atom to which they are attached form a C5-C10 cycloalkyl group.

[0075] In some embodiments, R1 and R2 are each independently selected from: C1-C4 alkyl optionally substituted with 1 or 2 phenyl groups, and phenyl optionally substituted with 1 or 2 substituents selected from C1-C4 alkyl, C1-C4 alkoxy and C1-C4 alkylthiol; or R1, R2 and the carbon atom to which they are attached form a C5-C7 cycloalkyl group.

[0076] In some embodiments, R3, R4, R5 and R6 are each independently selected from the group consisting of hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl and halogen; or, R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C12 cycloalkyl group, which is optionally substituted with 1, 2, 3, 4, 5 or 6 substituents selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy and halogen.

[0077] In some embodiments, R3, R4, R5 and R6 are each independently selected from: hydrogen and C1-C10 alkyl; or, R4, the carbon attached to R4, R5 and the carbon attached to R5 together form a C4-C12 cycloalkyl, and the C4-C12 cycloalkyl is optionally substituted with 1, 2, 3, 4, 5 or 6 C1-C10 alkyl.

[0078] In some embodiments, R3 and R6 are hydrogen.

[0079] In some embodiments, R4 and R5 are each independently selected from: hydrogen and C1-C10 alkyl; or, R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C8 cycloalkyl, which is optionally substituted with 1, 2, 3 or 4 C1-C6 alkyl.

[0080] In some embodiments, R4 and R5 are each independently selected from: hydrogen and C1-C6 alkyl; or, R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C5-C7 cycloalkyl, which is optionally substituted with 1, 2, 3 or 4 C1-C4 alkyl.

[0081] In some embodiments, R7 is a C1-C10 alkyl group, preferably a C1-C6 alkyl group, and more preferably a C1-C4 alkyl group.

[0082] In some embodiments, Y - Selected from: chloride, fluoride, bromide, nitrate, acetate and trifluoroacetate, Y - Acetate is preferred.

[0083] In some embodiments, in Formula I, R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl and substituted or unsubstituted C6-C14 aryl; the C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl and C6-C14 aryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, and C1-C10 alkylthiol; R3, R4, R5 and R6 are each independently selected from: hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl and halogen; R7 is C1-C6 alkyl.

[0084] In some embodiments, in Formula I, R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl and substituted or unsubstituted C2-C10 alkynyl; the C1-C10 alkyl, C2-C10 alkenyl and C2-C10 alkynyl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C6-C14 aryl and 5-14 membered heteroaryl; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl; R3 and R6 are each independently selected from: hydrogen, C1-C10 alkyl and halogen; R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C8 cycloalkyl, and the C4-C8 cycloalkyl is optionally substituted with 1, 2, 3, 4, 5 or 6 C1-C10 alkyl; R7 is selected from: C1-C6 alkyl.

[0085] In some embodiments, in Formula I, R1 and R2 are each independently selected from: C1-C6 alkyl, and C6-C10 aryl optionally substituted with 1, 2, 3 or 4 substituents selected from C1-C6 alkyl, C1-C6 alkoxy and C1-C6 alkylthiol; R3, R4, R5 and R6 are each independently selected from: hydrogen and C1-C6 alkyl; R7 is C1-C4 alkyl.

[0086] In some embodiments, in Formula I, R1 and R2 are each independently a C1-C6 alkyl group optionally substituted with 1, 2, 3 or 4 C6-C10 aryl groups; or R1, R2 and the carbon atom to which they are attached form a C5-C7 cycloalkyl group; R3 and R6 are all hydrogen; R4, the carbon atom to which R4 is attached, R5 and the carbon atom to which R5 is attached together form a C5-C7 cycloalkyl group, which is optionally substituted with 1, 2, 3 or 4 C1-C6 alkyl groups; and R7 is selected from a C1-C6 alkyl group.

[0087] In some embodiments, in Formula I, R1 and R2 are each independently selected from: C1-C4 alkyl, and phenyl optionally substituted with 1 or 2 substituents selected from C1-C4 alkyl, C1-C4 alkoxy and C1-C4 alkylthiol; R3 and R6 are both hydrogen; R4 and R5 are each independently selected from: hydrogen and C1-C6 alkyl; R7 is C1-C4 alkyl.

[0088] In some embodiments, in Formula I, R1 and R2 are each independently a C1-C4 alkyl group optionally substituted with 1 or 2 phenyl groups; or R1, R2 and the carbon atom to which they are attached form a C5-C7 cycloalkyl group; R3 and R6 are all hydrogen; R4, the carbon atom attached to R4, R5 and the carbon atom attached to R5 together form a C5-C7 cycloalkyl group, and the C5-C7 cycloalkyl group is optionally substituted with 1, 2, 3 or 4 C1-C4 alkyl groups; R7 is selected from a C1-C4 alkyl group.

[0089] In some embodiments, the compound of Formula I is selected from:

[0090]

[0091]

[0092] Among them, Y - The definition of is as described above.

[0093] Preferably, the compound of formula I is selected from:

[0094]

[0095] Unless otherwise specified, the structural formulas described herein are intended to include all isomeric forms (e.g., enantiomers, diastereomers, and geometric isomers (or conformers)): for example, R and S configurations containing asymmetric centers, (Z) and (E) isomers of double bonds, etc. Therefore, single stereochemical isomers of the compounds of the present invention or mixtures of their enantiomers, diastereomers, or geometric isomers (or conformers) are all within the scope of the present invention.

[0096] The present invention also provides fluorescent dyes, dye compositions, or contrast agents comprising a compound of Formula I of the present invention and an optional solvent. Suitable solvents for use in the present invention include, but are not limited to, buffer solutions, preferably PBS buffer solutions. Preferably, the compound of Formula I in the fluorescent dye, dye composition, or contrast agent is entrapped by a phospholipid derivative. Phospholipid derivatives are commonly used in the art for encapsulating or delivering molecules. The phospholipid derivative is preferably DSPE-mPEG2000.

[0097] The present invention also provides a kit for fluorescent imaging of cells or animals, which contains the compound of formula I of the present invention and an optional solvent, or contains the fluorescent dye, dye composition or contrast agent of the present invention.

[0098] The present invention provides the use of a compound of Formula I of the present invention in preparing a reagent for use in cell fluorescence imaging or animal fluorescence imaging, or in preparing a contrast agent. The cell may be a living cell, such as a living HeLa cell. The animal may be a mammal, such as a mouse or a human. The reagent or contrast agent can be used in laparoscopic surgery and / or fluorescence-guided surgery. The reagent or contrast agent can be used for imaging of blood vessels (such as cardiovascular), tumors, lymph nodes, nerves, bile ducts, ureters, and the gastrointestinal tract.

[0099] The present invention has the following beneficial effects:

[0100] The present application provides a novel super-absorbent cyanine dye with absorption and emission wavelengths around 800 nm, or even greater than 800 nm. The dye has high absorption intensity and good stability, and can be used as a contrast agent for clinical application.

[0101] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended to illustrate the present invention only and are not intended to limit the scope of the invention. The experimental methods in the following examples, for which specific conditions are not specified, are generally based on conventional conditions or the conditions recommended by the manufacturer. Unless otherwise stated, percentages and parts are calculated by weight.

[0102] Example 1: Preparation of Compound 8

[0103]

[0104] (1) Synthesis of Compound 2: Compound 1 (2.94 g, 1.00 eq., 19.98 mmol) and potassium carbonate (4.14 g, 1.50 eq., 29.97 mmol) were weighed and dissolved in 40 mL of acetonitrile. Ethyl iodide (3.74 g, 1.20 eq., 23.98 mmol) was quickly added to the mixture, and the mixture was refluxed and stirred under argon for 24 h. The solvent was removed by rotary evaporation and purified by column chromatography (petroleum ether (PE) / ethyl acetate (EA) = 15:1, v / v) to obtain 3.05 g of a red solid, which was Compound 2, with a yield of 87%.

[0105] (2) Synthesis of Compound 3: Compound 2 (2.00 g, 1.00 eq., 11.42 mmol) was weighed into a flask and 80% hydrazine hydrate (2.00 eq., 22.84 mmol) was quickly added. Under argon, the mixture was heated and stirred for 4 h. After the reaction, ice-water mixture was added to the reaction mixture, and a light pink solid precipitated. Filtration yielded 1.71 g of Compound 3, with a yield of 93%.

[0106] (3) Synthesis of compound 4a: Compound 3 (1.00 g, 1.00 eq., 6.20 mmol) was weighed into a flask and dissolved in 15 mL of N,N-dimethylformamide (DMF). 60% pure NaH (0.74 g, 3.00 eq., 18.60 mmol) was slowly added under an ice bath. After the mixture was allowed to react for 30 min, iodoethane (3.87 g, 4.00 eq., 24.80 mmol) was added to the flask. After the addition was complete, the mixture was transferred to room temperature and reacted for 2 h. After the reaction was completed, extraction was performed with an EA / H2O system. The organic layers were combined, dried over anhydrous sodium sulfate, and then rotary evaporated to remove the organic solvent. The mixture was purified by column chromatography (PE / EA = 30:1, v / v) to obtain 1.12 g of light yellow oily compound 4a with a yield of 83%. 1 H NMR (400MHz, CDCl3) δ7.22(tt,J=7.6,1.2Hz,1H),7.10(dd,J=7.5,1.3Hz,1H),7.02(td,J=7.4,1.1Hz,1H),6.82(d,J=7.8 Hz,1H),3.78-3.70(m,2H),1.94-1.84(m,2H),1.79-1.68(m,2H),1.20(td,J=7.2,0.9Hz,3H),0.51(td,J=7.4,0.9Hz,6H). 13 C NMR(101MHz, CDCl3)δ179.45,143.28,132.02,127.40,122.71,122.03,107.67,54.01,53.37,34.26,30.66,12.72,8.52.HRMS(EI)m / zcalcd.for C 14 H 19 NO,[M] + :217.1462,found:217.1465.

[0107] (4) Synthesis of compound 5a: Compound 4a (0.10 g, 1.00 eq., 0.46 mmol) was weighed into a flask and dissolved in tetrahydrofuran. Under argon protection, the mixture was placed in an ice-water bath and 2.5 M methyl lithium (1.84 mL, 10.00 eq., 4.60 mmol) was added dropwise. After the injection, the flask was transferred to room temperature. After the reaction was completed, the mixture was neutralized with saturated ammonium chloride solution and extracted with dichloromethane (CH2Cl2). After drying over anhydrous sodium sulfate, the organic solvent was removed by rotary evaporation to obtain the intermediate. The intermediate was dissolved in CH2Cl2, 0.5 mL of methanesulfonic acid was added dropwise, and the reaction was allowed to proceed overnight. Saturated sodium bicarbonate solution was added to adjust the pH of the reaction system to neutral, and the mixture was extracted with CH2Cl2 / H2O. The mixture was separated, dried over anhydrous sodium sulfate, and the solvent was removed by rotary evaporation to obtain a brown-yellow viscous liquid, which was compound 5a. It was directly used in the next step without purification.

[0108] (5) Synthesis of compound 7: Chemical Communications, 2019, 55, 5934-5937.

[0109] (6) Synthesis of Compound 8: Compound 7 (0.04 g, 1.00 eq., 0.23 mmol), compound 5a (0.22 g, 3.00 eq., 0.70 mmol), and sodium acetate (0.06 g, 3.00 eq., 0.70 mmol) were weighed into a 25 mL round-bottom flask. 2.00 mL of acetic acid was added to fully dissolve the compound, followed by 2.00 mL of acetic anhydride. Under argon protection, the mixture was heated to 120°C and reacted for 6 h. After the reaction, the mixture was cooled to room temperature and purified by column chromatography (CH2Cl2:CH3OH=20:1, v / v) to obtain 0.11 g of a dark green solid with a purple-red metallic luster, which was Compound 8, with a yield of 74%. 1 H NMR (400MHz, CDCl3) δ8.32(d,J=14.0Hz,2H),7.44-7.40(m,2H),7.33-7.29(m,2H),7.26(q,J=3.8Hz,2H),7.20(d,J=8.0Hz,2H),6.32(d,J=1 4.1Hz,2H),4.27(q,J=7.2Hz,4H),2.74(t,J=6.1Hz,4H),2.30-2.18(m,8H),2.03-1.97(m,2H),1.44(t,J=7.0Hz,6H),0.45(d,J=7.2Hz,12H). 13C NMR (101MHz, CDCl3) δ169.10,143.55,143.36,137.34,128.93,127.11,125.29,122 .23,110.31,101.71,60.10,39.79,34.84,26.50,12.59,8.53,8.50.HRMS(ESI)m / z calcd.forC 38 H 48 ClN2 + ,[M] + :567.3501,found:567.3505.

[0110] Example 2: Preparation of Compound 9

[0111]

[0112] (1) The synthesis of compounds 2, 3, and 7 was the same as in Example 1.

[0113] (2) Synthesis of Compound 4b The synthesis method of step (3) of Example 1 was repeated, except that iodopropane was used instead of iodoethane. The yield was 61%. 1 H NMR (400MHz, CDCl3) δ7.14(td,J=7.7,1.3Hz,1H),7.04(dd,J=7.4,1.3Hz,1H),6.95(td,J=7.5,1.0Hz,1H),6.75(d,J=7.8Hz,1H),3.66(q,J=7. 2Hz,2H),1.80-1.70(m,2H),1.64-1.55(m,2H),1.13(t,J=7.2Hz,3H),0 .88(tdd,J=13.3,7.4,3.5Hz,2H),0.76-0.68(m,2H),0.67-0.63(m,6H). 13 C NMR (101MHz, CDCl3) δ179.58,162.29,142.83,132.71,127.22,122.56,121.89 ,107.59,52.83,40.20,36.25,34.13,31.16,17.17,13.98,12.53.HRMS(EI)m / z calcd.for C 16 H 23 NO,[M] + :245.1775,found:245.1778.

[0114] (3) The synthesis of compound 5b was the same as step (4) in Example 1.

[0115] (4) The synthesis of compound 9 was the same as step (6) in Example 1, with a yield of 57%. 1 H NMR (400MHz, CDCl3) δ8.34(d,J=14.0Hz,2H),7.38(t,J=7.6Hz,2H),7.29(d,J=7.3Hz, 2H),7.24(t,J=7.4Hz,2H),7.12(d,J=7.8Hz,2H),6.16(d,J=14.0Hz,2H),4.10(q,J=7. 1Hz,4H),2.66(t,J=6.1Hz,4H),2.12(ddd,J=26.8,12.4,4.3Hz,8H),1.98-1.94(m,2H ),1.38(d,J=7.0Hz,6H),0.88-0.83(m,4H),0.71(d,J=7.1Hz,12H),0.58-0.50(m,4H). 13 C NMR (101MHz, CDCl3) δ169.84,150.66,143.66,142.96,138.11,128.85,126.63,125.41,122.13,110.21,101. 16,68.23,67.81,58.99,44.33,39.41,26.23,20.97,20.54,18.55,17.16,14.09,14.02,12.31.HRMS(ESI)m / z calcd.for C 42 H 56 ClN2 + ,[M] + :623.4127,found:623.4131.

[0116] Example 3: Preparation of Compound 14

[0117]

[0118] (1) The synthesis of compounds 2 and 7 was the same as in Example 1.

[0119] (2) Synthesis of Compound 4c: Compound 2 (0.50 g, 1.00 eq., 2.85 mmol) was weighed and dissolved in dry tetrahydrofuran. 2M phenylmagnesium chloride (9.99 mL, 7.00 eq., 19.98 mmol) was added dropwise in an ice bath under argon protection. After the reaction, the mixture was neutralized with saturated ammonium chloride solution and extracted with CH2Cl2. The mixture was separated and dried over anhydrous sodium sulfate. The organic solvent was removed by rotary evaporation and purified by column chromatography (PE / EA = 60:1, v / v) to obtain 0.65 g of a light yellow solid, namely, Compound 4c, with a yield of 73%. 1HNMR(400MHz,CD3OD)δ7.36(ddd,J=7.8,6.1,1.3Hz,1H),7.30-7.22(m,6H),7.20-7.16(m,4 H),7.16-7.12(m,2H),6.78-6.73(m,1H),3.87(q,J=7.2Hz,2H),1.28(td,J=7.2,2.1Hz,3H). 13 C NMR (101MHz, CDCl3) δ178.37,152.27,150.36,134.60,130.85,130.18,129.31,127.06,124.32,117.03,110.77,72.73,25.25,20.96.HRMS (EI) m / z calcd.forC 22 H 19 NO,[M] + :313.1462found:313.1469.

[0120] (3) The synthesis of compound 5c was the same as step (4) in Example 1.

[0121] (4) The synthesis of compound 14 was the same as step (6) in Example 1, with a yield of 71%. 1 H NMR (400MHz, CDCl3) δ7.70 (d, J = 13.5Hz, 1H), 7.38 (t, J = 7.8Hz, 2H), 7.31 (q, J = 5.5Hz, 12H), 7.26-7.18 (m, 10H), 7.18-7. 09(m,5H),6.28-6.05(m,2H),4.38-4.22(m,4H),2.46(d,J=6.4Hz,4H),1.75(t,J=6.3Hz,2H),1.49(q,J=8.1,7.7Hz,6H). 13 C NMR (101MHz, CDCl3) δ175.88,142.03,141.15,140.62,140.48,129.27,129.15,129.05,128.94,128.50,128.36,127.96,12 7.82,125.63,125.54,125.03,110.79,66.46,39.97,39.81,26.28,24.14,23.03,20.34,19.05,12.29,12.24.HRMS(ESI)m / z calcd.for C 54 H 48 ClN2 + ,[M] +:759.3501,found:759.3508.

[0122] Example 4: Preparation of Compound 15

[0123]

[0124] (1) The synthesis of compounds 2 and 7 was the same as in Example 1.

[0125] (2) Synthesis of Compound 4d The synthesis method of step (2) of Example 3 was repeated, except that p-tolylmagnesium chloride was used instead of phenylmagnesium chloride. The yield was 70%. 1 H NMR (400MHz, CD3OD) δ7.34 (td, J=7.7, 1.3Hz, 1H), 7.21 (dd, J=7.5, 1.3Hz, 1H), 7.11-7.05 (m, 8H), 6 .96(d,J=8.2Hz,1H),6.68-6.63(m,1H),3.85(q,J=7.2Hz,2H),2.30(s,6H),1.27(t,J=7.2Hz,3H). 13 C NMR (101MHz, CDCl3) δ177.43,142.15,139.16,136.88,133.65,129.14,128.2 7,128.08,126.15,122.60,108.60,61.82,35.06,21.05,12.79.HRMS(EI)m / z calcd.for C 24 H 23 NO,[M] + :341.1775,found:341.1779.

[0126] (3) The synthesis of compound 5d was the same as step (4) in Example 1.

[0127] (4) The synthesis of compound 15 was the same as step (6) in Example 1, with a yield of 76%. 1 H NMR (400MHz, CD3OD) δ7.78(d,J=13.8Hz,2H),7.39(d,J=7.1Hz,4H),7.25(d,J=7.6Hz,2H),7.15(q,J=8.2Hz,18H),6.28(d ,J=13.8Hz,2H),4.30(q,J=7.1Hz,4H),2.47(t,J=6.1Hz,4H),2.30(s,12H),1.70(t,J=6.1Hz,2H),1.46(t,J=7.2Hz,6H). 13C NMR (101MHz, CD3OD) δ171.83,152.15,148.84,143.44,143.23,139.12,138.89,130.55,130.11,129.69,128.8 0,126.69,126.11,112.08,102.75,67.34,54.83,40.43,27.11,21.83,21.11,12.46.HRMS(ESI)m / zcalcd.for C 58 H 56 ClN2 + ,[M] + :815.4127,found:815.4137.

[0128] Example 5: Preparation of Compound 16

[0129]

[0130] (1) The synthesis of compounds 2 and 7 was the same as in Example 1.

[0131] (2) Synthesis of Compound 4e: Compound 2 (1.00 g, 1.00 eq., 5.71 mmol) was weighed and dissolved in 20 mL of CH2Cl2. Aluminum trichloride (4.57 g, 6.00 eq., 34.25 mmol) was slowly added in an ice bath. Anisole (2.47 g, 4.00 eq., 22.83 mmol) was then added, and the reaction solution was transferred to room temperature. After the reaction was completed, the mixture was neutralized with saturated sodium bicarbonate solution, extracted several times with CH2Cl2 / H2O, separated, and the organic layer was dried over anhydrous sodium sulfate. The solvent was removed by rotary evaporation, and the mixture was purified by column chromatography (PE / EA = 40:1, v / v) to obtain 1.50 g of white solid powder, namely Compound 4e, with a yield of 70%. 1 H NMR (400MHz, CDCl3) δ7.35-7.27(m,2H),7.24-7.15(m,4H),7.10(td,J=7.5,1.0Hz,1H),6.97( d,J=7.8Hz,1H),6.89-6.81(m,4H),3.87(q,J=7.2Hz,2H),3.80(s,6H),1.34(t,J=7.2Hz,3H). 13C NMR (101MHz, CDCl3) δ177.69,158.72,142.05,134.25,133.85,129.46,128.07,12 6.08,122.59,113.81,108.65,61.04,55.28,35.05,12.80.HRMS(EI)m / zcalcd.for C 24 H 23 NO3,[M] + :373.1673,found:373.1681.

[0132] (3) The synthesis of compound 5e was the same as step (4) in Example 1.

[0133] (4) The synthesis of compound 16 was the same as step (6) in Example 1, with a yield of 75%. 1 H NMR (400MHz, CDCl3) δ7.73(d,J=13.8Hz,2H),7.38-7.33(m,2H),7.14(d,J=8.9Hz,10H),7.11(s,2H),6.85-6.80(m,10H),6 .20(d,J=13.9Hz,2H),4.29(d,J=7.3Hz,4H),3.78(s,12H),2.48(t,J=6.2Hz,4H),1.80-1.73(m,2H),1.49(t,J=7.2Hz,6H). 13 C NMR (101MHz, CDCl3) δ169.11,167.17,159.03,158.93,142.84,141.87,132.62,129.74,129.58,125.44,12 4.88,123.50,114.38,114.27,110.72,100.97,65.30,55.39,55.33,29.71,12.31.HRMS(ESI)m / zcalcd.for C 58 H 56 ClN2O4 + ,[M] + :879.3924,found:879.3927.

[0134] Example 6: Preparation of Compound 17

[0135]

[0136] (1) The synthesis of compounds 2 and 7 was the same as in Example 1.

[0137] (2) Synthesis of Compound 4f The synthesis method of step (2) of Example 5 was repeated, except that methyl phenyl sulfide was used instead of anisole. The yield was 70%. 1 H NMR (400MHz, CD3OD) δ7.34 (td, J=7.7, 1.3Hz, 1H), 7.22 (dd, J=7.6, 1.3Hz, 1H), 7.18-7. 13(m,4H),7.12-7.06(m,6H),3.84(q,J=7.1Hz,2H),2.41(s,6H),1.26(t,J=7.2Hz,3H). 13 CNMR(101MHz,CD3OD)δ173.01,171.71,167.50,165.20,152.94,139.99,129.0 4,123.18,120.31,111.57,75.80,75.48,56.49,51.39.HRMS(EI)m / zcalcd.for C 24 H 23 NOS2,[M] + :405.1216,found:405.1219.

[0138] (3) The synthesis of compound 5f was the same as step (4) in Example 1.

[0139] (4) The synthesis of compound 17 was the same as step (6) in Example 1, with a yield of 71%. 1 H NMR (400MHz, CD3OD) δ7.76(d,J=13.8Hz,2H),7.41(s,4H),7.29(d,J=7.6Hz,2H),7.21(s,18H),6.32(d,J=1 3.8Hz,2H),4.32(q,J=7.4Hz,4H),2.51(d,J=7.7Hz,4H),2.45(s,12H),1.74(s,2H),1.47(t,J=7.2Hz,6H). 13 CNMR(101MHz,CD3OD)δ171.29,148.62,143.49,142.70,140.51,138.17,130.36,130.22,129.21, 127.54,126.86,126.07,112.28,102.95,67.04,40.54,27.12,22.06,15.52,12.51.HRMS(ESI)m / z calcd.for C 58 H 56 ClN2S4 + ,[M] +:943.3010,found:943.3014.

[0140] Example 7: Preparation of Compound 18

[0141]

[0142] (1) The synthesis of compound 7 was the same as that in Example 1.

[0143] (2) Synthesis of compound 12: Compound 10 (2.00 g, 1.00 eq., 12.18 mmol) and compound 11 (1.57 g, 1.50 eq., 18.26 mmol) were weighed and dissolved in 40 mL of ethanol. The mixture was refluxed with stirring under argon for 24 h. The solvent was removed by rotary evaporation and purified by column chromatography (PE / EA = 80:1, v / v) to obtain 1.99 g of a reddish-brown viscous liquid, which was compound 12, with a yield of 76%. 1 H NMR (400MHz, CD3OD) δ7.43-7.40 (m, 1H), 7.34 (t, J = 1.4Hz, 2H), 2.26 (s, 3H), 1.33 (s, 9H), 1.30 (s, 6H). 13 CNMR(101MHz,CD3OD)δ190.14,151.42,150.16,146.57,125.68,119.67,119.45,54.87,35.73,32.18,23.46.HRMS(EI)m / z calcd.for C 15 H 21 N,[M] + :215.1669,found:215.1672.

[0144] (3) Synthesis of Compound 13: Compound 12 (2.00 g, 1.00 eq., 9.29 mmol) was weighed and dissolved in 40 mL of toluene. Ethyl iodide (2.90 g, 2.00 eq., 18.58 mmol) was quickly added to the mixture. Under argon, the mixture was heated to 120°C and reacted for 24 h. Clear solid precipitated, which was filtered to obtain 3.00 g of pink solid powder, Compound 13, with a yield of 87%. 1 HNMR (400MHz, CDCl3) δ7.63 (d, J=8.6Hz, 1H), 7.57 (dd, J=8.5, 1.8Hz, 1H), 7.50 (d, J= 1.8Hz,1H),4.73(q,J=7.5Hz,2H),3.11(s,3H),1.61(d,J=10.4Hz,9H),1.34(s,9H). 13CNMR(101MHz, CDCl3)δ194.29,154.37,141.53,138.34,126.83,119.99,114.72,54.53,45.44,35.39,31.40,23.23,16.77,13.58.HRMS(EI)m / z calcd.for C 17 H 26 N + ,[M] + :244.2060,found:244.2034.

[0145] (4) Synthesis of Compound 18: Triethylamine (3.00 eq.) was used as a base, acetic anhydride was used as a solvent, and the reaction was carried out at room temperature. The rest of the reaction was the same as step (6) in Example 1. The yield was 79%. 1 H NMR (400MHz, CDCl3) δ8.34(s,1H),8.30(s,1H),7.42(dd,J=8.4,1.9Hz,2H),7.36(d,J=1.8Hz,2H),7.10(d,J=8.4Hz,2H),6.18(s,1H) ,6.14(s,1H),4.21(q,J=7.3Hz,4H),2.71(t,J=6.1Hz,4H),1.97(q,J=6.2Hz,2H),1.71(s,12H),1.44(t,J=7.2Hz,6H),1.35(s,18H). 13 C NMR (101MHz, CDCl3) δ171.73,150.06,149.19,143.96,140.94,139.53,126.86,125.82,119.11,110. 17,100.67,49.44,39.93,34.98,31.54,28.11,26.60,23.12,20.71,12.46.HRMS(ESI)m / zcalcd.for C 42 H 56 ClN2 + ,[M] + :623.4127,found:623.4131.

[0146] Example 8: Synthesis of BSW-X series compounds

[0147] 8.1 Synthesis of key intermediates

[0148] (1) Synthesis of Intermediate 1

[0149]

[0150] It was prepared by a two-step reaction according to the method in Tetrahedron Letters., 2018, 59, 3409-3412.

[0151] (2) Synthesis of Intermediate 2

[0152]

[0153] Intermediate 1 (100 mmol, 16.1 g, 1 equiv.) was placed in a 500 mL round-bottom flask and added with 100 mL of anhydrous dichloromethane, followed by sonication until completely dissolved. Anhydrous aluminum chloride (300 mmol, 40 g, 3 equiv.) was slowly added portionwise to the solution in an ice-salt bath. The mixture was stirred for 1 h. A solution of 2,5-dichloro-2,5-dimethylhexane (300 mmol, 54.9 g, 3 equiv.) in anhydrous dichloromethane (100 mL) was then slowly added to the reaction solution using a constant pressure dropping funnel. The ice-salt bath was removed, and the mixture was heated to 40°C and refluxed for 12 h. After confirming complete reaction of the starting materials by thin-layer chromatography (TLC), the reaction solution was rapidly poured into 1 L of ice water and then extracted with dichloromethane (200 mL × 3). The three organic phases were combined, washed with saturated NaCl, dried over anhydrous NaSO, and concentrated by vacuum distillation. Finally, the mixture was purified by silica gel column chromatography using petroleum ether / ethyl acetate = 30 / 1 (v / v) as the final eluent to obtain intermediate 2 as a white powdery solid (18.2 g, yield: 67%). 1 H NMR (400MHz, CDCl3) δ7.21 (s, 1H), 6.74 (s, 1H), 3.76 (q, J = 7.2Hz, 2H), 3.46 (s, 2H), 1.69 (s, 4H), 1.31 (s, 6H), 1.27 (d, J = 2.4Hz, 9H). 13 C NMR (100MHz, CDCl3) δ174.99,144.67,142.15,138.80,122.80,122.51,105.74, 35.76,35.11,34.72,34.61,34.18,32.07,31.65,12.82.HRMS-ESI:calcdfor,[C 18 H 25 NO+H] + :272.2009,[M+H] + :found 272.2013.

[0154] (3) Synthesis of Intermediate 3

[0155]

[0156] Prepared by "one-step reaction" according to the method in Chemical Communications., 2019, 55, 5934-5937.

[0157] (4) Synthesis of Intermediate 4

[0158]

[0159] Prepared by "four-step reaction" according to the method in the literature Organic Letters., 2020, 22, 2931-2934.

[0160] (5) Synthesis of Intermediate 5

[0161]

[0162] Intermediate 4 (1 mmol, 269 mg, 1 equiv.) was placed in a 100 mL thick-walled pressure bottle, followed by the addition of 10 mL of anhydrous acetonitrile and iodoethane (20 mmol, 1.6 mL, 20 equiv.). The reaction mixture was refluxed at 85°C for 8 h. After confirmation of complete reaction by thin-layer chromatography, the mixture was cooled to room temperature and concentrated by vacuum distillation. Purification by silica gel column chromatography using dichloromethane / methanol = 20 / 1 (v / v) as the final eluent afforded Intermediate 5 (406 mg, 95% yield) as a pale purple solid powder.

[0163] 1 H NMR (400MHz, CDCl3) δ7.48 (s, 1H), 7.44 (s, 1H), 4.76 (q, J = 7.4Hz, 2H), 3.15 (s, 3H), 1.73 (s, 4H), 1.63 (s, 9H), 1.36 (s, 6H), 1.32 (s, 6H). 13 C NMR (100MHz, CDCl3) δ194.34,148.14,147.41,138.74,138.58,121.40,112.68,54.22, 53.52,45.24,35.26,35.13,34.59,32.16,32.11,23.44,16.97,13.69.HRMS-ESI:calcd for;C 21 H 32 N + :298.2529,[M] + :found 298.2537.

[0164] 8.2 Synthesis of Cyanine Dye Precursor Molecule MX

[0165] (1) Synthesis of compound M-Et

[0166]

[0167] like Figure 1 MX, the precursor molecule of the BSW series compounds, was prepared using General Synthesis Method A, using the synthesis of M-Et as an example. Compound Intermediate 2 (5 mmol, 1.36 g, 1 equiv.) was placed in a 100 mL round-bottom flask, and 20 mL of ultra-dry DMF was added. The mixture was sonicated until completely dissolved. Under ice-bath conditions, 60 wt% solid sodium hydride (30 mmol, 1.2 g, 6 equiv.) was added portionwise. The reaction was stirred at this temperature for 1 h, followed by the addition of iodoethane (30 mmol, 2.4 mL, 6 equiv.) at once. The reaction solution was allowed to react at room temperature for 4 h. After confirmation of complete reaction by thin-layer chromatography, the reaction solution was rapidly poured into 50 mL of ice water to quench the excess sodium hydride. The solution was then extracted with dichloromethane (100 mL x 3). The three organic phases were combined, washed with saturated NaCl, and dried over anhydrous Na2SO4. The organic phase was concentrated by vacuum distillation and purified by silica gel column chromatography using petroleum ether / ethyl acetate = 50:1 (v / v) as the final eluent to afford compound M-Et (671 mg, 41% yield) as a purple-red solid powder. 1 H NMR (400MHz, CDCl3) δ7.02(s,1H),6.69(s,1H),3.75(q,J=7.2Hz,2H),1.86(dd,J=13.4,7.4Hz,2H),1.75(d d,J=13.4,7.5Hz,2H),1.69(s,4H),1.30(s,6H),1.27(s,6H),1.23(t,J=7.2Hz,3H),0.58(t,J=7.4Hz,6H). 13 C NMR (100MHz, CDCl3) δ179.97,143.92,140.83,138.62,129.60,120.96,105.14,53. 81,35.22,34.66,34.31,34.18,32.21,32.10,30.51,12.94,8.81.HRMS-ESI:calcd for,[C 22 H 33 NO+H] + :328.2635,[M+H] + :found328.2643.

[0168] (2) Synthesis of compound M-Pr

[0169]

[0170] According to the general synthesis method A, RX is 1-iodopropane (30mmol, 2.9mL, 6equiv.), to obtain a pale yellow powdery solid compound M-Pr (533mg, yield: 30%). 1 H NMR (400MHz, CDCl3) δ7.03 (s, 1H), 6.68 (s, 1H), 3.74 (q, J = 7.2Hz, 2H), 1.68 (s, 4H), 1.30 (s, 6H), 1.27(s,6H),1.22(t,J=7.2Hz,4H),1.04–0.96(m,2H),0.95–0.85(m,2H),0.77(t,J=7.2Hz,6H). 13 C NMR (100MHz, CDCl3) δ180.15,143.82,140.52,138.56,130.40,126.11,120.90,105.12,52.81,46.58,45.24, 40.24,35.22,34.65,34.28,34.16,32.20,32.10,22.87,22.37,22.06,17.53,14.39,12.87.HRMS-ESI:calcd for,[C 24 H 37 NO+H] + :356.2948,[M+H] + :found356.2951.

[0171] (3) Synthesis of compound M-Bu

[0172]

[0173] According to the general synthetic method A, RX is 1-bromobutane (30mmol, 3.2mL, 6equiv.), to obtain a pale white powdery solid compound M-Bu (902mg, yield: 47%). 1 H NMR (400MHz, CDCl3) δ7.02 (s, 1H), 6.68 (s, 1H), 3.74 (q, J = 7.2Hz, 2H), 1.86–1.70 (m, 4H), 1.69 (s, 4H), 1.31 (s, 6H), 1.26 (s, 6H) ),1.22(t,J=7.2Hz,3H),1.16(dt,J=14.0,6.9Hz,4H),0.98(tt,J=12.9,7.0Hz,2H),0.90–0.80(m,2H),0.77(t,J=7.4Hz,6H). 13C NMR (100MHz, CDCl3) δ180.18,143.80,140.51,138.53,130.43,120.93,105.12,52.54,37.62, 35.24,35.22,34.65,34.28,34.16,32.18,32.09,26.17,22.88,13.84,12.86.HRMS-ESI:calcd for,[C 26 H 41 NO+H] + :383.3188,[M+H] + :found383.3182.

[0174] (4) Synthesis of compound M-Bn

[0175]

[0176] According to the general synthesis method A, RX is benzyl bromide (30mmol, 3.6mL, 6equiv.), to obtain a pale white powdery solid compound M-Bn (2.1g, yield: 93%). 1 H NMR (400MHz, CDCl3) δ7.08–7.02(m,6H),6.92–6.86(m,5H),6.29(s,1H),3.38(q,J=7.2Hz, 2H),3.22–3.07(m,4H),1.71–1.60(m,5H),1.26(s,6H),1.16(s,6H),0.68(t,J=7.2Hz,3H). 13 C NMR (100MHz, CDCl3) δ178.36,144.34,140.25,137.70,136.35,130.46,128.52,128.40,127.98,127.67,127.49,126 .33,123.36,105.16,55.08,43.04,35.18,35.16,34.55,34.11,34.01,32.07,31.98,11.97.HRMS-ESI:calcdfor,[C 32 H 37 NO+H] + :452.2948,[M+H] + :found 452.2955.

[0177] (5) Synthesis of compound M-Cba

[0178]

[0179] According to the general synthetic method A, RX is 1,4-diiodobutane (5mmol, 660μL, 1equiv.), to obtain a light pink powdery solid compound M-Cba (553mg, yield: 34%). 1 H NMR (400MHz, CDCl3) δ7.12(s,1H),6.71(s,1H),3.74(q,J=7.2Hz,2H),2.16–2.03(m,4H),2.01–1.9 2(m,2H),1.86–1.77(m,2H),1.68(d,J=8.4Hz,4H),1.31(s,6H),1.28(s,6H),1.25(d,J=7.2Hz,3H). 13 C NMR (100MHz, CDCl3) δ181.80,143.96,139.83,138.85,134.63,120.41,105.26,53.76, 38.47,35.21,35.16,34.68,34.56,34.25,32.18,32.06,26.71,12.92.HRMS-ESI:calcd for,[C 22 H 31 NO+H] + :326.2478,[M] + :found 326.2483.

[0180] 8.3 Synthesis of Target Dyes BSW-X Series Dyes

[0181] (1) Synthesis of compound BSW-Et

[0182]

[0183] like Figure 1The BSW-X series of compounds were prepared using General Synthesis Method B, using the synthesis of BSW-Et as an example. Compound M-Et (0.5 mmol, 157 mg, 1 equiv.) was placed in a 100 mL, heat-dried, round-bottom flask. 20 mL of anhydrous tetrahydrofuran was quickly added and sonicated until completely dissolved. In an ice-salt bath and argon protection, methyllithium reagent (2.5M, 1.5mmol, 0.6mL, 3equiv.) was slowly added dropwise. After the addition was complete, the ice-salt bath was removed, and the reaction solution was stirred at room temperature for 4h. After confirming that the raw material M-Et had reacted completely by thin-layer chromatography, saturated NH4Cl was added to quench the excess lithium reagent, and the mixture was extracted with ethyl acetate (50mL×3). The organic phases were combined and washed with saturated NaCl, dried over anhydrous Na2SO4, and the solvent was removed by distillation under reduced pressure. Then, 10mL of dichloromethane was added to dissolve it again, and methanesulfonic acid (0.2mL) was slowly added dropwise. The mixture was reacted at room temperature for 10min, and then dichloromethane was added for extraction (100mL×3). The three organic phases were combined, washed with saturated NaCl, and dried over anhydrous Na2SO4. The organic phase was concentrated by distillation under reduced pressure to obtain a yellow oily compound S-Et, which was directly used for the next reaction without further separation and purification. The unpurified compound S-Et, intermediate 3 (0.25 mmol, 43 mg, 1 equiv.), and sodium acetate (0.5 mmol, 41 mg, 2 equiv.) were placed in a 50 mL round-bottom flask. Acetic anhydride (5 mL) and glacial acetic acid (5 mL) were added sequentially. The reaction was stirred at 130°C under argon for 4 hours. After complete reaction of the compound S-Et, as monitored by TLC, the mixture was cooled to room temperature and concentrated by vacuum distillation. The mixture was purified by silica gel column chromatography using dichloromethane / methanol = 30 / 1 (v / v) as the final eluent to afford compound BSW-Et (49 mg, 23% yield) as a black powdery solid. 1 H NMR (400MHz, CDCl3) δ8.30(d,J=14.0Hz,2H),7.17(d,J=4.1Hz,2H),6.98(d,J=5.6Hz,2H),6.25(d,J=14.0Hz,2H),4.20(q,J=7.2Hz,4H),2.72(t ,J=6.2Hz,4H),2.27–2.21(m,4H),2.17–2.11(m,4H),1.99(t,J=5.9Hz,2 H),1.72(s,8H),1.43(s,6H),1.34(s,12H),1.30(s,12H),0.47(s,12H). 13C NMR (100MHz, CDCl3) δ169.04,149.69,146.06,142.91,142.80,141.48,134.61,126.65,120.28,107.58,101.4 9,68.41,59.86,39.65,34.98,34.81,34.69,32.21,32.16,26.57,20.83,18.89,12.69,8.74.HRMS-ESI:calcd for,C 54 H 76 ClN2 + :787.5692,[M] + :found787.5696.

[0184] (2) Synthesis of compound BSW-Pr

[0185]

[0186] According to the general synthesis method B, using compound M-Pr (0.5mmol, 178mg, 1equiv.) as raw material, a black-green powdery solid compound BSW-Pr (38mg, yield: 17%) was obtained. 1 H NMR(400MHz, CDCl3)δ8.31(d,J=14.0Hz,2H),7.19(s,2H),6.97(s,2H),6.22(d,J=14 .1Hz,2H),4.18(q,J=7.2Hz,4H),2.72(t,J=6.2Hz,4H),2.21–2.13(m,4H),2.09–2.0 4(m,4H),2.01(d,J=4.5Hz,2H),1.72(s,8H),1.42(s,6H),1.34(s,12H),1.30(s,12H ),0.91(dd,J=10.5,7.3Hz,4H),0.76(t,J=7.1Hz,12H),0.64(dd,J=12.6,7.5Hz,4H). 13CNMR(100MHz,CDCl3)δ169.57,149.69,145.98,143.00,142.74,141.09,138.77 ,135.49,126.52,121.49,120.18,107.62,101.38,100.67,68.41,68.32,64.41 ,58.72,58.50,44.69,44.40,39.56,34.96,34.89,34.67,32.19,32.14,30.67, 26.49,20.79,18.87,17.38,14.38,14.32,13.75,12.61,12.54.HRMS-ESI:calcd for,C 58 H 84 ClN2 + :843.6318,[M] + :found 843.6321.

[0187] (3) Synthesis of compound BSW-Bu

[0188]

[0189] According to the general synthetic method B, using compound M-Bu (0.5mmol, 192mg, 1equiv.) as raw material, a black powdery solid compound BSW-Bu (24mg, yield: 10%) was obtained. 1 H NMR (400MHz, CDCl3) δ8.30(d,J=13.9Hz,2H),7.17(d,J=5.6Hz,2H),6.98(s,2H),6.22( d,J=14.0Hz,2H),4.20(q,J=8.0Hz,4H),2.73(t,J=6.3Hz,4H),2.21–2.07(m,8H),2.00( t,J=6.3Hz,2H),1.72(s,8H),1.43(t,J=7.0Hz,6H),1.35(s,12H),1.30(s,12H),1.19–1 .13(m,8H),0.89(q,J=6.7Hz,4H),0.76(d,J=7.3Hz,12H),0.56(dt,J=12.5,6.3Hz,4H). 13C NMR (100MHz, CDCl3) δ169.56,168.73,149.65,145.96,142.96,142.68,14 1.11,138.72,135.42,135.13,126.48,121.46,120.21,107.62,101.36,10 0.67,58.48,58.27,41.95,41.61,39.61,34.96,34.88,34.65,32.16,32.1 3,26.52,25.86,22.52,20.79,13.59,12.60,12.53.HRMS-ESI:calcdfor,C 62 H 92 ClN2 + :899.6944,[M] + :found 899.6948.

[0190] (4) Synthesis of compound BSW-Bn

[0191]

[0192] According to the general synthetic method B, using compound M-Bn (0.5mmol, 226mg, 1equiv.) as raw material, a black powdery solid compound BSW-Bn (36mg, yield: 13%) was obtained. 1 H NMR(400MHz, CDCl3)δ8.80(d,J=14.1Hz,2H),7.28(s,1H),7.12(t,J=7.3Hz,4H ),7.06(t,J=7.3Hz,8H),6.73(d,J=7.5Hz,9H),6.67(s,2H),6.14(d,J=14.1Hz ,2H).3.74(q,J=7.2Hz,2H),2.16–2.03(m,4H),2.01–1.92(m,2H),1.86–1.77( m,2H),1.68(d,J=8.4Hz,4H),1.31(s,6H),1.28(s,6H),1.25(d,J=7.2Hz,3H). 13 C NMR (100MHz, CDCl3) δ178.35,144.34,140.25,137.70,136.35,130.46,127.67,127.49,126.33,123 .36,105.16,55.08,43.04,35.18,35.16,34.55,34.11,34.01,32.07,31.98,11.97.HRMS-ESI:calcd for,C74 H 84 ClN2 + :1035.6318,[M] + :found 1035.6322.

[0193] (5) Synthesis of compound BSW-Cba

[0194]

[0195] According to the general synthetic method B, using compound M-Cba (0.5mmol, 163mg, 1equiv.) as raw material, a black powdery solid compound BSW-Cba (13mg, yield: 6%) was obtained. 1 H NMR (400MHz, CDCl3) δ8.30(d,J=13.9Hz,2H),7.17(d,J=5.6Hz,2H),6.98(s,2H),6.22( d,J=14.0Hz,2H),4.20(q,J=8.0Hz,4H),2.73(t,J=6.3Hz,4H),2.21–2.07(m,8H),2.00( t,J=6.3Hz,2H),1.72(s,8H),1.43(t,J=7.0Hz,6H),1.35(s,12H),1.30(s,12H),1.19–1 .13(m,8H),0.89(q,J=6.7Hz,4H),0.76(d,J=7.3Hz,10H),0.56(dt,J=12.5,6.3Hz,4H). 13 C NMR (100MHz, CDCl3) δ171.91,150.62,144.50,141.75,141.15,128.89,127.39,125.3 7,122.33,110.79,101.00,49.37,40.13,28.08,26.79,20.70,12.50.HRMS-ESI:calcd for,C 54 H 72 ClN2 + :783.5379,[M] + :found 783.5381.

[0196] (6) Synthesis of compound BSW-Me

[0197]

[0198] Only according to the condensation reaction in general synthetic method B, intermediate 5 (0.5 mmol, 213 mg, 2 equiv.) and intermediate 3 (0.25 mmol, 43 mg, 1 equiv.) were reacted to obtain a golden powder solid compound BSW-Me (100 mg, yield: 47%). 1 H NMR (400MHz, CDCl3) δ8.33(s,1H),8.30(s,1H),7.28(d,J=2.1Hz,2H),7.01(s,2H),6.19(s,1H),6.16(s,1H),4.23(q,J=7.2Hz ,4H),2.74(t,J=6.2Hz,4H),2.03–1.93(m,2H),1.71(s,8H),1.70(s,12H),1.46(t,J=7.2Hz,6H),1.34(s,12H),1.32(s,12H). 13 C NMR (100MHz, CDCl3) δ171.69,149.92,146.11,143.90,142.79,139.81,138.62,127.03,120.26,108 .06,100.86,49.16,39.97,34.99,34.93,34.75,32.15,28.26,26.85,20.80,12.62.HRMS-ESI:calcd for,C 50 H 68 ClN2 + :731.5066,[M] + :found731.5074.

[0199] Test Example 1

[0200] The compounds 8, 9, 14-18 and the control dye M780 (chemical formula: ) in dichloromethane. The results are as follows Figure 2 As shown, it can be seen that the absorption wavelengths of compounds 8, 9, 14-18 are around 780 nm to around 820 nm.

[0201] The tests were performed using a Shimadzu UV-2600 ultraviolet-visible spectrometer and a PTI steady-state fluorescence instrument. Figure 3The UV-visible absorption spectra (left) and fluorescence emission spectra (right) of the reference dye M780 and the BSW-X series dyes in dichloromethane are shown. It can be seen that the absorption and emission wavelengths of the BSW-X series dyes are red-shifted compared to the reference dye M780, with the BSW-Bn series dyes red-shifting by 44 nm and 38 nm, respectively.

[0202] Test Example 2

[0203] The photophysical properties of dyes M780 and BSW-X series dyes in different solvents (DCM, MeOH, DMF, MeCN, DMSO) were tested using a Shimadzu UV-2600 UV-visible spectrometer and a PTI steady-state fluorometer. The results are shown in Table 1. The fluorescence quantum yield Φ was measured with indocyanine green (ICG) as a reference (DMSO, Φ ICG =13%, reference Org.Biomol.Chem,.2020,18(46),9385-9397).

[0204] Table 1: Photophysical properties of BSW-X series dyes and reference dye M780 in different organic solvents

[0205]

[0206]

[0207] The absorption and emission spectra and basic spectral properties of compounds 8, 9, 14-18 and the control dye M780 in different solvents (dichloromethane (DCM), methanol (MeOH), acetonitrile (MeCN) and N, N-dimethylformamide (DMF)) were tested using a Horiba Duetta UV fluorescence spectrometer. The results are shown in Tables 2-5. F Indocyanine green (ICG) was used as a reference (MeOH, Φ ICG =7.8%, reference Theranostics, 2013, 3(9), 692-702).

[0208] Table 2: Photophysical properties of compounds 8, 9, 14-18 and control dye M780 in DCM

[0209]

[0210] Table 3: Photophysical properties of compounds 8, 9, 14-18 and control dye M780 in MeOH

[0211]

[0212]

[0213] Table 4: Photophysical properties of compounds 8, 9, 14-18 and control dye M780 in MeCN

[0214]

[0215] Table 5: Photophysical properties of compounds 8, 9, 14-18 and control dye M780 in DMF

[0216]

[0217] Test Example 3

[0218] Compound 14 was prepared into a 1 μM PBS buffer solution and incubated with HeLa living cells for about 15 minutes. The incubated cells were imaged by confocal microscopy with a shooting parameter of λ ex =808nm,λ em =830nm. The results are as follows Figure 4 shown.

[0219] Test Example 4

[0220] Compound 14 and DSPE-mPEG2000 were dissolved in CH2Cl2 solution and dried under reduced pressure to obtain a film. 5 mL of PBS buffer solution (pH = 7.4) was added and ultrasonicated for 15 min. The supernatant was filtered through a 0.22 μm microporous membrane to obtain nanomicelles. The mice were injected into the tail vein and anesthetized and placed on a near-infrared in vivo fluorescence imaging platform. ex =808nm excitation light and 1350nm long pass filter. Figure 5 As shown, the nanomicelles encapsulated with compound 14 and DSPE-mPEG2000 successfully achieved near-infrared second-zone in vivo fluorescence imaging of the liver, sternum, tibia and other parts of mice.

Claims

1. A compound of formula I, characterized in that It has the structure shown below: In Formula I, R1 and R2 are each independently selected from the group consisting of substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl, substituted or unsubstituted C1-C10 alkoxy, substituted or unsubstituted C1-C10 alkylthiol, substituted or unsubstituted C3-C12 cycloalkyl, substituted or unsubstituted 3-12 membered heterocyclyl, substituted or unsubstituted C6-C14 aryl, substituted or unsubstituted 5-14 membered heteroaryl and halogen; the C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C1 -C10 alkoxy, C1-C10 alkylthiol, C3-C12 cycloalkyl, 3-12 membered heterocyclyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 alkylthiol, C3-C12 cycloalkyl, 3-12 membered heterocyclyl, C6-C14 aryl, 5-14 membered heteroaryl and halogen; said 3-12 membered heterocyclyl and 5-14 membered heteroaryl containing 1, 2 or 3 heteroatoms selected from N, O and S; Or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl group; R3, R4, R5 and R6 are each independently selected from the group consisting of hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, halogen, hydroxy, amino, nitro and carboxyl; Alternatively, R4, the carbon to which R4 is attached, R5, and the carbon to which R5 is attached together form a C4-C12 cycloalkyl group, which is optionally substituted with 1, 2, 3, 4, 5, or 6 substituents selected from C1-C10 alkyl, C1-C10 alkoxy, and halogen; R7 is selected from the group consisting of: C1-C10 alkyl, C2-C10 alkenyl, and C2-C10 alkynyl; Y - Selected from: 1 / 2 sulfate, chloride, fluoride, bromide, nitrate, 1 / 2 carbonate, bicarbonate, acetate, 1 / 2 oxalate and trifluoroacetate.

2. The compound according to claim 1, wherein R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl, substituted or unsubstituted C6-C14 aryl, substituted or unsubstituted 5-14 membered heteroaryl and halogen; said C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, C1-C10 alkylthiol, C6-C14 aryl, 5-14 membered heteroaryl and halogen; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl; Preferably, R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C6-C14 aryl and substituted or unsubstituted 5-14 membered heteroaryl; the C1-C10 alkyl, C6-C14 aryl and 5-14 membered heteroaryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy, C1-C10 alkylthiol, C6-C14 aryl and 5-14 membered heteroaryl; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl group; Preferably, R1 and R2 are each independently selected from: C1-C10 alkyl optionally substituted by 1, 2, 3 or 4 C6-C14 aryl groups, and C6-C14 aryl optionally substituted by 1, 2, 3 or 4 substituents selected from C1-C10 alkyl, C1-C10 alkoxy and C1-C10 alkylthiol; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl group.

3. The compound according to claim 1, wherein R3, R4, R5 and R6 are each independently selected from the group consisting of hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl and halogen; or, R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C12 cycloalkyl group, which is optionally substituted with 1, 2, 3, 4, 5 or 6 substituents selected from the group consisting of C1-C10 alkyl, C1-C10 alkoxy and halogen; Preferably, R3, R4, R5 and R6 are each independently selected from: hydrogen and C1-C10 alkyl; or, R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C12 cycloalkyl, and the C4-C12 cycloalkyl is optionally substituted with 1, 2, 3, 4, 5 or 6 C1-C10 alkyl groups; Preferably, R3 and R6 are hydrogen; R4 and R5 are each independently selected from: hydrogen and C1-C10 alkyl; or, R4, the carbon attached to R4, R5 and the carbon attached to R5 together form a C4-C8 cycloalkyl, and the C4-C8 cycloalkyl is optionally substituted with 1, 2, 3 or 4 C1-C6 alkyl.

4. The compound according to claim 1, wherein R7 is a C1-C10 alkyl group, preferably a C1-C6 alkyl group, more preferably a C1-C4 alkyl group.

5. The compound according to claim 1, wherein Y - Selected from: chloride, fluoride, bromide, nitrate, acetate and trifluoroacetate, Y - Acetate is preferred.

6. The compound according to claim 1, wherein In Formula I, R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl, substituted or unsubstituted C2-C10 alkynyl and substituted or unsubstituted C6-C14 aryl; the C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl and C6-C14 aryl are optionally substituted with 1, 2, 3 or 4 substituents selected from the group consisting of C1-C10 alkyl, C2-C10 alkenyl, C1-C10 alkoxy, and C1-C10 alkylthiol; R3, R4, R5 and R6 are each independently selected from: hydrogen, C1-C10 alkyl, C2-C10 alkenyl, C2-C10 alkynyl and halogen; R7 is C1-C6 alkyl; or R1 and R2 are each independently selected from: substituted or unsubstituted C1-C10 alkyl, substituted or unsubstituted C2-C10 alkenyl and substituted or unsubstituted C2-C10 alkynyl; the C1-C10 alkyl, C2-C10 alkenyl and C2-C10 alkynyl are optionally substituted by 1, 2, 3 or 4 substituents selected from the following groups: C6-C14 aryl and 5-14 membered heteroaryl; or R1, R2 and the carbon atom to which they are attached form a C5-C12 cycloalkyl; R3 and R6 are each independently selected from: hydrogen, C1-C10 alkyl and halogen; R4, the carbon to which R4 is attached, R5 and the carbon to which R5 is attached together form a C4-C8 cycloalkyl, and the C4-C8 cycloalkyl is optionally substituted by 1, 2, 3, 4, 5 or 6 C1-C10 alkyl; R7 is selected from: C1-C6 alkyl.

7. The compound according to claim 1, wherein In Formula I, R1 and R2 are each independently selected from: C1-C6 alkyl, and C6-C10 aryl optionally substituted with 1, 2, 3 or 4 substituents selected from C1-C6 alkyl, C1-C6 alkoxy and C1-C6 alkylmercapto; R3, R4, R5 and R6 are each independently selected from: hydrogen and C1-C6 alkyl; R7 is C1-C4 alkyl; or R1 and R2 are each independently a C1-C6 alkyl group optionally substituted with 1, 2, 3 or 4 C6-C10 aryl groups; or R1, R2 and the carbon atom to which they are attached form a C5-C7 cycloalkyl group; R3 and R6 are all hydrogen; R4, the carbon atom to which R4 is attached, R5 and the carbon atom to which R5 is attached together form a C5-C7 cycloalkyl group, and the C5-C7 cycloalkyl group is optionally substituted with 1, 2, 3 or 4 C1-C6 alkyl groups; R7 is selected from: C1-C6 alkyl group.

8. The compound according to claim 1, wherein The compound of formula I is selected from: Y - The definition as described in claim 1 or 5; preferably, the compound of formula I is selected from:

9. A fluorescent dye, dye composition, contrast agent or kit, characterized in that: The fluorescent dye, dye composition or contrast agent contains the compound of formula I according to any one of claims 1 to 8 and an optional solvent; the kit contains the compound of formula I according to any one of claims 1 to 8 and an optional solvent, or contains the fluorescent dye, dye composition or contrast agent; Preferably, the solvent is a buffer solution, preferably a PBS buffer solution; Preferably, the compound of formula I is entrapped by a phospholipid derivative, and the phospholipid derivative is preferably DSPE-mPEG2000.

10. Use of the compound of formula I according to any one of claims 1 to 8 in the preparation of a reagent for cell fluorescence imaging or animal fluorescence imaging, or in the preparation of a contrast agent.

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