Amphiphilic poly(amino acid) linear block copolymer for drug delivery use and nanoparticles thereof

Abstract

The present invention relates to the field of polymer chemistry, and more particularly, to poly(amino acid) copolymers for drug delivery applications and their use. In particular, the present invention relates to linear copolymers comprising a polysarcosine block containing 15 to 99 sarcosine structural units, pSar, and a poly(amino acid) block containing 8 to 120 amino acid structural units, pAA.

Description

Technical Field

[0001] The present invention relates to the field of polymer chemistry, and more particularly, to poly(amino acid) copolymers for drug delivery applications and their use.

Background Art

[0002] Active pharmaceutical ingredients (APIs) often need to be mixed with one or more excipients to render the pharmaceutical usable. Excipients are typically inert constituents having specific functions in the pharmaceutical form: excipients can be used, for example, as binders, lubricants, coating agents, or bulking agents. Depending on the treatment indication, the drug can be administered by various routes (e.g., topical, oral, parenteral), which require various final drug dosage forms and thus the use of suitable excipients.

[0003] Polymeric excipients are widely used in the formulation of pharmaceuticals intended for all possible routes of administration. Polymeric excipients include natural compounds such as cellulose, semi-synthetic compounds such as cellulose derivatives, and synthetic polymers such as poly(ethylene glycol) (PEG), polylactide, or polyamide. The physical or chemical properties of an API can be modified using a polymeric excipient, for example, its viscosity can be changed or its solubility can be increased.

[0004] Amphiphilic block copolymers are particularly interesting excipients for solubilizing hydrophobic APIs in water. Composed of at least one hydrophilic block covalently attached to one hydrophobic block, they self-assemble in water to form nano-sized aggregates above the critical aggregation concentration (CAC). These resulting supramolecular assemblies, also referred to as nanoparticles (NP), typically have sizes in the range of 10 - 100 nm and can have various morphologies. For example, micelles have a spherical core-shell structure where the hydrophobic block forms a hydrophobic core stabilized by a hydrophilic shell composed of the hydrophilic block. The hydrophobic API can be filled and separated in the core during micelle formation. API-loaded micelles prepared in diluents commonly used for parenteral administration, such as saline, do not require co-solvents such as Cremophor® EL (polyoxyethylated castor oil) which are known to have several adverse effects and can increase the solubility of the API. Another advantage is that the API is not covalently bound to the copolymer, and thus this drug form can be applied to a wide range of APIs.

[0005] Furthermore, in addition to increasing the aqueous solubility of the API, the nanoparticles provide various advantages such as preventing early API degradation, controlling its release, improving its bioavailability, and enhancing its uptake into tumor tissue by passive targeting via the enhanced permeability and retention effect (EPR effect) for anti-tumor applications.

[0006] PEG is the most commonly used hydrophilic block due to its stealth effect. However, PEG is not biodegradable and may cause an immune response at high doses or in long-term administration.

[0007] Polysarcosine (pSar) is a good alternative to PEG as it possesses similar properties such as hydrophilicity, stealthiness, and low toxicity. Since pSar is based on the endogenous amino acid derivative sarcosine, N-methylated glycine, it has the advantage of being biodegradable.

[0008] Amphiphilic polysarcosine-poly(amino acid) copolymers have been developed in recent years for their biodegradability and ability to self-assemble in water into nanoparticles.

[0009] U.S. Patent No. 10,836,869 discloses the use of such types of copolymers for solubilizing hydrophobic molecules. These multiblock copolymers contain numerous sarcosine units and amino acid units, which cause challenges in costly synthesis and subsequent purification and scale-up for industrial production. SUMMARY OF THE INVENTION

[0010] Therefore, there remains a need for polymers that can solubilize hydrophobic APIs without showing side effects when used in drug delivery applications.

[0011] The present invention is directed to linear copolymers comprising a polysarcosine block, pSar, containing 15 to 99 sarcosine constitutional units and a poly(amino acid) block, pAA, containing 8 to 120 amino acid constitutional units.

[0012] Preferably, the linear copolymer has a hydrophilic fraction, f(pSar), in the range of 5 to 80%, preferably 10 to 70%, where f(pSar) is the percent ratio of the number-average molar mass of the pSar block based on the number-average molar mass of the copolymer.

[0013] Preferably, the pAA block has a hydrophobicity coefficient, H, of -0.50 or greater, preferably -0.25 or greater, preferably 0.00 or greater, preferably 0.50 or greater, more preferably 0.80 or greater.

[0014] Preferably, the amino acid constitutional units of the pAA block are derived from hydrophobic amino acids preferably selected from the group consisting of alanine, valine, norleucine, leucine, isoleucine, methionine, phenylalanine, tryptophan, proline, tyrosine, their derivatives, protected hydrophilic amino acids, and combinations thereof.

[0015] The derivative of the hydrophobic amino acid is preferably a protected hydrophobic amino acid.

[0016] Preferably, the copolymer is a copolymer of Formula I or Formula II

[0017]

Chemical formula

[0018] (wherein, x is the number of sarcosine structural units and is an integer in the range of 15 to 99, y + z is the number of amino acid structural units and is an integer in the range of 8 to 120, R y group and R z groups are independently selected from amino acid side chain groups, R 1a group and R 1b groups are independently selected from H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, and heteroaryl, R 2 group is selected from H and nitrogen protecting groups) selected from.

[0019] Preferably, x is an integer in the range of 20 to 95, more preferably 24 to 85.

[0020] Preferably, y + z is an integer in the range of 8 to 110, more preferably 12 to 100.

[0021] Preferably, y + z is an integer in the range of 8 to 50, more preferably 9 to 45, even more preferably 12 to 40.

[0022] Preferably, y + z is an integer in the range of 55 to 110, more preferably 60 to 100.

[0023] Preferably, y is a number in the range of 0 to 120, more preferably 0 to 110, preferably 5 to 100, preferably 9 to 95, preferably 10 to 90.

[0024] Preferably, z is a number in the range of 0 to 120, more preferably 0 to 110, preferably 5 to 100, preferably 9 to 95, preferably 10 to 90.

[0025] At least one of z or y is different from 0.

[0026] Preferably, R y is the side chain of a hydrophobic L - amino acid, and R z is the side chain of a hydrophobic D - amino acid.

[0027] Preferably, R y is selected from the side chains of L - leucine, L - phenylalanine, L - tyrosine, L - glutamate γ - benzyl, L - glutamate γ - tert - butyl, and L - cyclohexylglycine.

[0028] Preferably, R z is selected from the side chains of D - leucine, D - phenylalanine, D - cyclohexylglycine, D - tyrosine, D - glutamate γ - benzyl, and D - glutamate γ - tert - butyl.

[0029] The present invention relates to a method for preparing the above - mentioned linear copolymer by polymerizing a sarcosine derivative and an amino acid derivative, wherein the derivatives are represented by the following formulas III and IV

[0030]

Chemical formula

[0031] (wherein, A is O or S, R y and R z are as defined above), and the method is also an object of the present invention.

[0032] The present invention also relates to nanoparticles comprising the above linear copolymer or a linear copolymer prepared according to the above method.

[0033] Preferably, the nanoparticles further comprise at least one active compound, preferably selected from hydrophobic compounds, particularly hydrophobic active pharmaceutical ingredients.

[0034] The nanoparticles preferably meet at least one of the following conditions: - A hydrodynamic diameter smaller than 400 nm, preferably in the range of 5 to 200 nm; - A polydispersity index lower than 0.70, preferably in the range of 0.02 to 0.70; - A loading efficiency of the active compound higher than 20%, preferably higher than 30%. of at least one of them.

[0035] The present invention further relates to a method for preparing the above nanoparticles, comprising the following steps: - Preparing an organic solution containing the copolymer of the present invention; - Then, mixing the organic solution with an aqueous solution while stirring; - Then, removing the organic solvent.

[0036] Preferably, the nanoparticles further comprise an active compound, and the method comprises the following steps: - Preparing an organic solution containing the copolymer of the present invention and at least one active compound; - Then, mixing the organic solution with an aqueous solution while stirring; - Then, removing the organic solvent.

[0037] Definition The following are definitions of various terms used herein to describe the present disclosure, and are further illustrated by the embodiments, sub - embodiments, and compounds disclosed herein. When the terms are used throughout this specification, either individually or as part of a larger group, these definitions apply to those terms, unless otherwise indicated in a particular instance.

[0038] As used in the present invention, the term "halogen" or "halo" refers to a fluorine, chlorine, bromine, or iodine atom.

[0039] As used in the present invention, the term "alkyl" refers to a straight - chain or branched - chain, monovalent saturated hydrocarbon chain. "(C1 - C 10 )alkyl" refers to an alkyl containing 1 to 10 carbon atoms.

[0040] The term "alkenyl" is given its ordinary meaning in the art and refers to an unsaturated hydrocarbon chain. "(C2 - C 10 )alkenyl" refers to an alkenyl containing 2 to 10 carbon atoms and including one or more carbon - carbon double bonds.

[0041] The term "alkynyl" is given its ordinary meaning in the art and refers to an unsaturated hydrocarbon chain. "(C2 - C 10 )alkynyl" refers to an alkynyl containing 2 to 10 carbon atoms and including one or more carbon - carbon triple bonds.

[0042] As used in the present invention, the term "cycloalkyl" refers to a hydrocarbon ring. "(C3 - C 10 )cycloalkyl" refers to a cycloalkyl having 3 to 10 carbon atoms, including but not limited to cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl.

[0043] As used herein, the term "aryl" refers to an aromatic hydrocarbon group containing one or more fused rings, and further one or more substituents such as halogen, (C1-C6) alkyl, -O(C1-C6) alkyl, etc., preferably containing 6 to 10 carbon atoms. For example, aryl includes phenyl group, benzyl group, or naphthyl group.

[0044] As used herein, the term "heteroaryl" refers to aryl containing one or more, especially one to four, advantageously one or two, carbon atoms each replaced by a heteroatom selected from sulfur atom, oxygen atom, and nitrogen atom, preferably a heteroatom selected from oxygen atom and nitrogen atom, especially nitrogen atom, of one or more, especially one or two, preferably one, fused hydrocarbon rings. It may be benzothiazolyl, furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, quinolyl, isoquinolyl, quinoxalyl, or indolyl.

[0045] The term "unit" or "structural unit" in this disclosure refers to a structural unit derived from the polymerization of monomers.

[0046] The term "linear copolymer" refers to a copolymer containing pSar block and pAA block having a linear structure as described in formula (I) or formula (II), for example. The term "linear copolymer" does not include non-linear copolymers such as multi-branched star polymers and more particularly three-branched star copolymers.

[0047] The term "sarcosine structural unit" or "sarcosine unit" refers to a unit derived from the monomer of sarcosine.

[0048] The term "amino acid structural unit" or "amino acid unit" refers to a unit derived from the monomer of amino acid.

[0049] The term "AA" is used to denote an amino acid. In the present disclosure, the term "AA" does not include glycine.

[0050] Amino acids are represented by the formula NH2-CHR-CO2H, where R represents the side chain group of each amino acid. The amino acids used in the present invention may be natural amino acids or non-natural amino acids. The term "natural amino acid" refers to any naturally occurring amino acid that can be found in proteins or in nature. These are L-alanine, L-arginine, L-asparagine, L-aspartate, L-cysteine, L-glutamate, L-glutamine, glycine, L-histidine, L-isoleucine, L-leucine, L-lysine, L-methionine, L-phenylalanine, L-proline, L-pyrolysine, L-selenocysteine, L-serine, L-threonine, L-tryptophan, L-tyrosine, and L-valine.

[0051] The term "non-natural amino acid" refers to any amino acid that is not included in the enumeration of naturally occurring amino acids. Non-natural amino acids include amino acids in which the side chain "R" is chemically modified, for example, by functionalization or a protecting group.

[0052] The term "amino acid side chain group", which is also defined as a "side chain group", refers to the R group of the α-carbon of any natural AA or non-natural AA as defined herein. For example, the side chain group of L-alanine is methyl, and the side chain group of γ-benzyl glutamate is the -(CH2)2CO2CH2C6H5 group.

[0053] The term "D-amino acid" refers to an amino acid in which the alpha carbon of the AA is in the D-configuration, also denoted as the D-isomer, and the term "L-amino acid" refers to an amino acid in which the alpha carbon of the AA is in the L-configuration, also denoted as the L-isomer.

[0054] The term "poly(amino acid)" or "pAA" is used to denote a block composed of linear polymer chains in which the constituent units are derived from amino acids or a mixture of amino acids and are covalently bonded by peptide bonds. pAA can be formed via ring-opening polymerization of amino acid monomers. If only L-amino acid monomers are used, the resulting block is a poly(L-amino acid) block. If only D-amino acid monomers are used, the resulting block is a poly(D-amino acid) block. If a mixture of L-amino acids and D-amino acids with unspecified sequence is used, the resulting block is a poly(L-amino acid-co-D-amino acid) block.

[0055] The term "Sar" is used to denote sarcosine.

[0056] The term "polysarcosine" or "pSar" is used to denote a block composed of linear polymer chains in which the constituent units are derived from sarcosine and are covalently bonded by peptide bonds.

[0057] The term "amino acid monomer" or "amino acid monomer" refers to an amino acid or any amino acid derivative that can be used in the polymerization process.

[0058] The term "sarcosine monomer" refers to sarcosine or any sarcosine derivative that can be used in the polymerization process.

[0059] The term "sarcosine derivative" or "amino acid derivative" refers to any reactive form of sarcosine or amino acid that can be used in the polymerization process. For example, for ring-opening polymerization, the derivative may be the N-carboxy anhydride (NCA) of an amino acid or sarcosine, or the N-thiocarboxy anhydride (NTA) of an amino acid or sarcosine.

[0060] As used herein, the term "initiator" or "polymerization initiator" refers to a molecule that reacts with a monomer to form a compound capable of reacting continuously with other monomers by chain growth to form a polymer.

[0061] The term "terminator" refers to a compound that reacts with the end of a living polymer chain to stop chain growth.

[0062] The term "capping agent" refers to a compound that reacts with the N-terminal portion of a polymer chain to covalently bond a functional group such as -C(O)CH3.

[0063] The terms "drug loading" and "loading" refer to particles containing an active compound such as an API that is encapsulated within the particles, for example, by encapsulation.

[0064] As used in the present invention, the expression "pharmaceutically acceptable" means useful in the preparation of pharmaceutical compositions and being generally safe and non-toxic for pharmaceutical use.

[0065] The terms "drug", "active pharmaceutical ingredient", "API", "medicine" and their derivatives are used interchangeably and refer to substances for use in the diagnosis, treatment, alleviation, management, or prevention of diseases.

[0066] The terms "particle" and "nanoparticle" according to the present invention are used interchangeably to denote an object obtained by the spontaneous self-assembly of block copolymers. For example, these nanoparticles may be micelles, polymersomes, or polyplexes.

[0067] "Polymer micelle" means an object characterized by a core-shell structure having a hydrophobic core and a hydrophilic shell, formed by the self-assembly of an amphiphilic copolymer.

[0068] "Polymersome" means a polymer-based vesicle, which is an object having a bilayer structure enclosing an aqueous compartment formed by self-assembly of an amphiphilic copolymer.

[0069] "Polyplex" means a polymer system containing complexed nucleic acids (e.g., DNA or RNA) formed by electrostatic interaction between the cationic groups of a polymer and negatively charged nucleic acids.

[0070] It is understood that any of the embodiments and preferred or advantageous disclosures described below can be combined with any of the other recited embodiments and preferred or advantageous disclosures.

[0071] Method NCA polymerization can be monitored by Fourier transform infrared spectroscopy (FTIR). For example, when the carbonyl bands associated with NCA at 1850 cm -1 and 1778 cm -1 disappear, the polymerization is considered complete.

[0072] The number of constitutional units of each monomer of the pSar block and the pAA block can be determined by proton ( 1 H) nuclear magnetic resonance (NMR).

[0073] The number average molar mass (M n ) and dispersity

[0074]

Number

[0075] of the copolymer can be determined by size exclusion chromatography (SEC).

[0076] The hydrodynamic diameter (D h) And the polydispersity index (PDI) can be determined by dynamic light scattering (DLS).

[0077] The loading efficiency (LE) can be determined using ultra - performance liquid chromatography (UPLC).

[0078] The loading content (LC) can be determined using size - exclusion chromatography (SEC).

[0079] The aqueous solubility of the API can be determined by any experimental method and analytical method such as UPLC.

[0080] The H hydrophobicity coefficient of the pAA block of the linear copolymer according to the present invention can be determined as follows.

[0081] The hydrophobicity coefficient of the block is determined according to the length and / or its composition of the block. The hydrophobicity coefficient H is defined by the following mathematical formula E1.

[0082] Mathematical formula E1: H = Alog P / n

[0083] Wherein, - "H" is the hydrophobicity coefficient of the pAA block; - Even if the amino acid of the PAA block has the configuration of D - amino acid or L - amino acid, "Alog P" is the simulated octanol / water partition coefficient of the PAA block having an amide functional group at its C - terminal and an acetamide functional group at its N - terminal; - "n" is the number of AA units in the pAA block (i.e., in particular n = y or n = z, and one of y or z is equal to 0).

[0084] When the pAA block is composed of various AA units, that is, in particular when both y and z are different from 0, the H coefficient is determined as the arithmetic mean of the H coefficients of each type of AA unit.

[0085] For example, for the block P(AA1y-co-AA2z) derived from two amino acid monomers, the H coefficient is determined by the following mathematical formula E2.

[0086] Mathematical formula E2: HP(AA1y-co-AA2z)=(yHAA1+zHAA2) / (y+z)

[0087] Alog P for the pAA block is obtained by the prediction model of the octanol / water partition coefficient defined by Ghose and Crippen, and is calculated using Biovia Draw19.1.NET.

[0088] - Version MDL.Draw.Editor19.1.0.1792 - Reference assemblies and loaded assemblies MDL.Cheshire: Loaded version = 5.1.0.22 MDL.CheshireLic: Loaded version = 5.1.0.22 MDL.CsInline: Reference version and loaded version = 3.0.4.47 MDL.Draw.Clipboard: Reference version and loaded version = 19.1.0.1792 MDL.Draw.Editor: Loaded version = 19.1.0.1792 MDL.Draw.Foundation: Reference version and loaded version = 19.1.0.1792 MDL.Draw.Foundation.PPChemAPIIO: Loaded version = 19.1.0.1792 MDL.Draw.Renderer: Reference version and loaded version = 19.1.0.1792 MDL.Draw.TextServicesWrapper: Reference version and loaded version = 19.1.0.1792 nalpp: Reference version = 19.1.0.1963 SandBar: Reference Version and Loaded Version = 1.4.3.1 SandDock: Reference Version and Loaded Version = 3.0.6.1

[0089] The models of Ghose and Crippen refer to the models described in the following documents:

[0090] Ghose, A.K.; Crippen, G.M. Atomic Physicochemical Parameters for Three-Dimensional-Structure-Directed Quantitative Structure-Activity Relationships. 2. Modeling Dispersive and Hydrophobic Interactions. J. Chem. Inf. Comput. Sci. 1987, 27(1), 21 - 35. https: / / doi.org / 10.1021 / ci00053a005

[0091] Ghose, A.K.; Viswanadhan, V.N.; Wendoloski, J.J. Prediction of Hydrophobic (Lipophilic) Properties of Small Organic Molecules Using Fragmental Methods: An Analysis of ALOGP and CLOGP Methods. J. Phys. Chem. A 1998, 102(21), 3762 - 3772. https: / / doi.org / 10.1021 / jp980230o

[0092] The specific protocols of each model are given in the examples.

Mode for Carrying Out the Invention

[0093] Surprisingly, it has been found that linear copolymers having a limited number of Sar units can increase the solubility of active compounds, preferably the solubility of hydrophobic compounds such as hydrophobic APIs.

[0094] Advantageously, the linear copolymers according to the invention are less expensive than the copolymers of the prior art because their synthesis is easy. Furthermore, the industrial scale-up of the copolymers according to the invention may also be easy.

[0095] In particular, the linear copolymers according to the invention can improve the aqueous solubility of hydrophobic compounds such as hydrophobic APIs, preferably by more than 100-fold, preferably by more than 200-fold, preferably by more than 500-fold, preferably by more than 1000-fold, preferably by more than 2000-fold, more preferably by more than 3000-fold, through their ability to self-assemble into nanoparticles.

[0096] Copolymer The present invention relates to a polysarcosine block, pSar, containing 15 to 99 sarcosine structural units; and a poly(amino acid) block, pAA, containing 8 to 120 amino acid structural units in a linear copolymer.

[0097] One skilled in the art will understand that when the pAA block is formed by various AAs, the order of each AA unit may be statistical or controlled.

[0098] One advantage of the copolymers according to the invention is that the copolymers are stable, biocompatible and easily degrade in vivo.

[0099] According to the present invention, the pSar block of the copolymer is hydrophilic, while the pAA block is less hydrophilic than the pSar block and thus has hydrophobic behavior. These properties make the copolymer amphiphilic and enable the copolymer to form stable nanoparticles, such as micelles. Furthermore, the nanoparticles formed by the copolymer of the present invention are biocompatible and easily degrade in vivo.

[0100] Using the amphiphilic properties of the pSar-pAA copolymer according to the present invention, nanoparticles can be formed. Advantageously, the nanoparticles can encapsulate active compounds, for example, to limit their degradation or to increase their solubility in water.

[0101] The limited number of structural units of the pSar-pAA copolymer of the present invention facilitates the preparation of each block and is attractive in terms of cost.

[0102] The pSar block contains a molecular chain of 15 to 99 sarcosine units, preferably 20 to 95, preferably 24 to 85, more preferably 28 to 80 sarcosine units.

[0103] In a preferred embodiment, the pSar block contains a molecular chain of 50 to 99 sarcosine units, preferably 55 to 95, preferably 60 to 85, more preferably 65 to 80 sarcosine units.

[0104] In another preferred embodiment, the pSar block contains a molecular chain of 15 to 50 sarcosine units, preferably 18 to 45, preferably 22 to 40, more preferably 25 to 35 sarcosine units.

[0105] AA that constitutes pAA is preferably selected from the enumeration further disclosed below. The selection is made so as to ensure that the pAA block obtained by polymerization is less hydrophilic than the pSar block. The pAA block can be recognized as a hydrophobic block.

[0106] Preferably, the pAA block contains a molecular chain of 8 to 120 AA units, preferably 8 or 9 to 110 units, preferably 12 to 100 units, more preferably 15 to 95 units of AA units.

[0107] In a preferred embodiment, the pAA block contains a molecular chain of 8 to 50 AA units, preferably 9 to 45 units, preferably 12 to 40 units, more preferably 15 to 35 units, or even 20 to 25 units of AA units.

[0108] In another preferred embodiment, the pAA block contains a molecular chain of 50 to 120 AA units, preferably 55 to 110 units, preferably 60 to 100 units, more preferably 65 to 95 units of AA units.

[0109] In a preferred embodiment, the linear copolymer is: - a polysarcosine block, pSar, containing 50 to 99 sarcosine units, preferably 55 to 95 units, preferably 60 to 85 units, more preferably 65 to 80 units of sarcosine units; and - a poly(amino acid) block, pAA, containing 8 to 50 AA units, preferably 9 to 45 units, preferably 12 to 40 units, more preferably 15 to 35 units, further 20 to 25 units of AA units and includes.

[0110] In a preferred embodiment, the linear copolymer is: - a polysarcosine block, pSar, containing 50 to 99 sarcosine units, preferably 55 to 95 units, preferably 60 to 85 units, more preferably 65 to 80 units of sarcosine units; and - a poly(amino acid) block, pAA, containing 50 to 120 AA units, preferably 55 to 110 units, preferably 60 to 100 units, more preferably 65 to 95 units of AA units and includes.

[0111] In a preferred embodiment, the linear copolymer is: - a polysarcosine block, pSar, containing 15 to 50 sarcosine units, preferably 18 to 45, preferably 22 to 40, more preferably 25 to 35 sarcosine units; and - a poly(amino acid) block, pAA, containing 8 to 50 AA units, preferably 9 to 45, preferably 12 to 40, more preferably 15 to 35, or even more preferably 20 to 25 AA units comprising.

[0112] In a preferred embodiment, the linear copolymer is: - a polysarcosine block, pSar, containing 15 to 50 sarcosine units, preferably 18 to 45, preferably 22 to 40, more preferably 25 to 35 sarcosine units; and - a poly(amino acid) block, pAA, containing 50 to 120 AA units, preferably 55 to 110, preferably 60 to 100, more preferably 65 to 95 AA units comprising.

[0113] Advantageously, the copolymer comprises two or more blocks, at least one block being pSar and at least one block being pAA. Preferably, the copolymer comprises two blocks, one block being pSar and one block being pAA.

[0114] Advantageously, the copolymer according to the invention has a hydrophilic fraction f(pSar) in the range of 5 to 80%, preferably 10 to 70%, preferably 15 to 60%, more preferably 20 to 50%. The hydrophilic fraction f(pSar) may also be in the range of 5 to 60% or 10 to 55%. The hydrophilic fraction, f(pSar), is the percentage ratio of the number-average molar mass (M n of the pSar block based on the M of the copolymer n ).

[0115] Advantageously, the copolymer has a hydrophobic fraction f(pAA) in the range of 20 to 90%, preferably 30 to 88%, preferably 40 to 85%, more preferably 50 to 80%. The hydrophobic fraction is the percentage of the M n of the hydrophobic pAA block based on the M n of the copolymer.

[0116] Advantageously, the copolymer according to the invention has a number-average molar mass, M, in the range of 500 g / mol to 50,000 g / mol, preferably 800 to 45,000 g / mol, preferably 1000 to 40,000 g / mol, preferably 1200 to 35,000 g / mol, more preferably 1400 to 32,000 g / mol. n It has.

[0117] Advantageously, the copolymer according to the invention has a number-average molar mass, M, in the range of 4500 g / mol to 50,000 g / mol, preferably 4800 to 40,000 g / mol, preferably 5200 to 30,000 g / mol, preferably 5500 to 25,000 g / mol, more preferably 6000 to 20,000 g / mol. n It has.

[0118] Advantageously, the linear copolymer according to the invention has a dispersity in the range of 1 to 2, preferably 1.0 to 1.8, more preferably 1.0 to 1.6.

[0119]

Number

[0120] Advantageously, the pAA block has an H hydrophobicity coefficient of -0.50 or more, preferably -0.25 or more, preferably 0.00 or more, preferably 0.50 or more, more preferably 0.80 or more. Typically, the pAA block has an H coefficient in the range of -0.50 to 20.00, preferably -0.25 to 18.00, preferably 0.00 to 15.00, more preferably 0.50 to 10.00, or even 0.80 to 6.00. The H hydrophobicity coefficient of the pAA block is determined by the mathematical formula E1 or E2 defined above.

[0121] Preferably, as long as the AA unit is hydrophobic compared to the Sar unit of the pSar block, the hydrophobic pAA block comprises, preferably consists of, natural amino acid units or unnatural amino acid units, AA units. According to the present invention, the pAA block does not contain sarcosine units.

[0122] Advantageously, the amino acids of the pAA block are D- and / or L-, where D- refers to the D-isomer of the amino acid and L- refers to the L-isomer of the amino acid. Preferably, the amino acids of the pAA block are a mixture of D-amino acids and L-amino acids, or L-amino acids only, or D-amino acids only. Preferably, when the amino acids are a D- / L- mixture, the molar ratio of D- / L- is in the range of 30 / 70 to 70 / 30, preferably 40 / 60 to 60 / 40, preferably 45 / 55 to 55 / 45, and more preferably 50 / 50.

[0123] Advantageously, the AA of pAA is selected from the group consisting of hydrophobic amino acids, protected hydrophobic amino acids, protected hydrophilic amino acids, and combinations thereof. The hydrophobic amino acids are preferably selected from the group consisting of alanine, valine, norleucine, leucine, isoleucine, methionine, phenylalanine, tryptophan, proline, tyrosine, and combinations thereof.

[0124] Advantageously, the AA of pAA is an amino acid having a side chain carrying at least one aryl group and / or at least one heteroaryl group. The aryl group and / or heteroaryl group may be inherently included in the side chain of the amino acid and / or added as a protecting group for the side chain of the AA. For example, the AA may be glutamic acid protected with a benzyl group.

[0125] Without being bound by any theory, it is believed that the aryl group and / or heteroaryl group can participate in, and facilitate, the encapsulation of hydrophobic compounds, such as hydrophobic APIs, by the linear copolymers of the present invention.

[0126] The functional groups of the side chains of AA can be protected by various protecting groups. Preferably, the protecting group contains at least one aryl group and / or at least one heteroaryl group.

[0127] The functional groups of the amino acid side chains, such as hydroxyl groups, amine groups, aldehyde groups, and carboxylic acid groups, can be protected by esters, carbonates, sulfonates, allyl esters, ethers, silyl ethers, alkyl ethers, arylalkyl ethers, and alkoxyalkyl ethers. The esters used to protect hydroxyl groups according to the present invention are formate, acetate, propionate, butanoate, pentanoate, crotonate, benzoate, benzoylformate, chloroacetate, trifluoroacetate, methoxyacetate, triphenylmethoxyacetate, p-chlorophenoxyacetate, 3-phenylpropionate, 4-oxopentanoate, 4,4-(ethylenedithio)pentanoate, pivaloate (trimethylacetate), crotonate, 4-methoxy-crotonate, benzoate, p-benzylbenzoate, 2,4,6-trimethylbenzoate.

[0128] Advantageously, when a carbonate is used to protect a hydroxyl group, the carbonate is selected from 9-fluorenylmethyl carbonate, ethyl carbonate, 2,2,2-trichloro-ethyl carbonate, 2-(trimethylsilyl)ethyl carbonate, 2-(phenylsulfonyl)ethyl carbonate, vinyl carbonate, allyl carbonate, and p-nitrobenzyl carbonate.

[0129] Advantageously, when a silyl ether is used to protect a hydroxyl group, the silyl ether is selected from among trimethylsilyl ether, triethylsilyl ether, tert-butyldimethylsilyl ether, tert-butyldiphenylsilyl ether, triisopropylsilyl ether, and other trialkylsilyl ethers.

[0130] Advantageously, when an alkyl ether, an alkoxyalkyl ether, and an arylalkyl ether are used to protect a hydroxyl group; the alkyl ether is selected from among methyl ether, benzyl ether, p-methoxybenzyl ether, 3,4-dimethoxybenzyl ether, trityl ether, tert-butyl ether, and allyl ether, or derivatives thereof; the alkoxyalkyl ether containing an acetal is selected from among methoxymethyl ether, methylthiomethyl ether, (2-methoxyethoxy)methyl ether, benzyloxymethyl ether, beta-(trimethylsilyl)ethoxymethyl ether, and tetrahydropyran-2-yl ether; and the arylalkyl ether is selected from among benzyl ether, p-methoxybenzyl (MPM) ether, 3,4-dimethoxybenzyl ether, o-nitrobenzyl ether, p-nitrobenzyl ether, p-halobenzyl ether, 2,6-dichlorobenzyl ether, p-cyanobenzyl ether, 2-picolyl ether, and 4-picolyl ether.

[0131] Advantageously, the amine group of the AA side chain can be protected by arylalkylamine, carbamate, allylamine, amide, and their derivatives including tert-butyloxycarbonylamino (-NHBOC), ethyloxycarbonylamino, methyloxycarbonylamino, trichloroethyloxycarbonylamino, allyloxycarbonylamino (-NHAlloc), benzyloxycarbonylamino (-NHCbz), allylamino, benzylamino (-NHBn), fluorenylmethylcarbonyl (-NHFmoc), formamide, acetamide, chloroacetamide, dichloroacetamide, trichloroacetamide, phenylacetamide, trifluoroacetamide, benzamide, and tert-butyldiphenylsilyl.

[0132] Advantageously, the aldehyde group of the AA side chain can be protected by acyclic acetal, hydrazone, imine, and more specifically, dimethyl acetal, diethyl acetal, diiso-propyl acetal, dibenzyl acetal, bis(2-nitrobenzyl) acetal, 1,3-dioxane, 1,3-dioxolane, semicarbazone, and their derivatives.

[0133] Advantageously, the carboxylic acid group of the AA side chain can be protected by an optionally substituted C1-C6 aliphatic ester, an optionally substituted aryl ester, a silyl ester, an activated ester, an amide, a hydrazide, for example, but not limited to, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, benzyl ester, and phenyl ester, and each group can be optionally substituted. Additional protected carboxylic acids include oxazoline and orthoester.

[0134] Those skilled in the art will know that the hydrophilicity of AA can be changed from hydrophilic to hydrophobic by the functional groups of the AA side chain using protecting groups.

[0135] Hydrophilic AAs that can be protected later to become hydrophobic include cysteine, tyrosine, serine, threonine, aspartic acid, glutamic acid, asparagine, lysine, histidine, arginine, glycine, and glutamine.

[0136] The protecting groups are preferably selected from alkyl ethers, alkoxyalkyl ethers, and arylalkyl ethers such as trityl, tert-butyl, benzyl; esters such as trifluoroacetate; arylalkylamines, carbamates, allylamines, amides, and their derivatives such as tert-butyloxycarbonylamino; and acetates.

[0137] Protected hydrophilic AAs preferably include β-trityl-asparagine, asparagine β-benzyl, S-benzyl-cysteine, cyclohexylglycine, glutamic acid γ-benzyl, glutamic acid γ-tert-butyl, ε-trifluoroacetyl-lysine, ε-Boc-lysine, ε-benzyl-lysine, β-benzyl-serine, O-acetyl-tyrosine, O-benzyl-tyrosine. A preferred protected hydrophilic AA is glutamic acid γ-benzyl.

[0138] Preferably, the linear copolymer is a copolymer of formula I or formula II

[0139]

Chemical formula

[0140] (wherein, x is the number of sarcosine structural units and is an integer in the range of 15 to 99, y + z is the number of amino acid structural units and is an integer in the range of 8 to 120, R y group and R z groups are independently selected from amino acid side chain groups, R 1a group and R 1bThe group is independently selected from H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, and heteroaryl, R 2 The group is selected from H and a nitrogen protecting group) and is selected from among them.

[0141] When the amino acid contains a surrounding cyclic side chain group, R y group and / or R z group is also bonded to the N atom of the structural unit. Then, the hydrogen atoms represented in formulas (I) and (II) are of course absent.

[0142] "x" is the total number of sarcosine structural units in the pSar block. Preferably, x is an integer in the range of 20 to 95, preferably 24 to 85, more preferably 28 to 80.

[0143] In a preferred embodiment, x is an integer in the range of 50 to 99, preferably 55 to 95, preferably 60 to 85, more preferably 65 to 80 sarcosine units.

[0144] In another preferred embodiment, x is an integer in the range of 15 to 50, preferably 18 to 45, preferably 22 to 40, more preferably 25 to 35 sarcosine units.

[0145] "y + z" is the total number of amino acid structural units. Preferably, y + z is an integer in the range of 8 or 9 to 110, preferably 12 to 100, more preferably 15 to 95.

[0146] In a preferred embodiment, y + z is an integer in the range of 8 to 50, preferably 9 to 45, preferably 12 to 40, more preferably 15 to 35, or further 20 to 25.

[0147] In a preferred embodiment, y + z is an integer in the range of 50 to 120, preferably 55 to 110, preferably 60 to 100, more preferably 65 to 95.

[0148] Advantageously, - x ranges from 50 to 99, preferably from 55 to 95, more preferably from 60 to 85, and even more preferably from 65 to 80, - y + z ranges from 8 to 50, preferably from 9 to 45, more preferably from 12 to 40, and even more preferably from 20 to 25.

[0149] Advantageously, - x ranges from 50 to 99, preferably from 55 to 95, more preferably from 60 to 85, and even more preferably from 65 to 80, - y + z ranges from 50 to 120, preferably from 55 to 110, more preferably from 60 to 100, and even more preferably from 65 to 95.

[0150] Advantageously, when x is in the range of 50 to 99, y + z is in the range of 50 to 120. Advantageously, when x is in the range of 55 to 95, y + z is in the range of 55 to 110. Advantageously, when x is in the range of 60 to 85, y + z is in the range of 60 to 100. Advantageously, when x is in the range of 65 to 80, y + z is in the range of 65 to 95.

[0151] Advantageously, - x ranges from 15 to 50, preferably from 18 to 45, more preferably from 22 to 40, and even more preferably from 25 to 35, - y + z ranges from 8 to 50, preferably from 9 to 45, more preferably from 12 to 40, and even more preferably from 15 to 35, and even more preferably from 20 to 25.

[0152] Advantageously, when x is in the range of 15 to 50, y + z is in the range of 8 to 50. Advantageously, when x is in the range of 18 to 45, y + z is in the range of 9 to 45. Advantageously, when x is in the range of 22 to 40, y + z is in the range of 12 to 40. Advantageously, when x is in the range of 25 to 35, y + z is in the range of 15 to 35 or even more preferably from 20 to 25.

[0153] Advantageously, - x ranges from 15 to 50, preferably from 18 to 45, more preferably from 22 to 40, and even more preferably from 25 to 35, - y + z ranges from 50 to 120, preferably from 55 to 110, more preferably from 60 to 100, and even more preferably from 65 to 95.

[0154] "y" is the number of AA units of the pAA sub-block contained in the pAA block. Preferably, "y" is a number in the range of 0 to 120, preferably 0 to 110, preferably 5 to 100, preferably 9 to 95, preferably 10 to 90, preferably 15 to 85, preferably 18 to 80, preferably 20 to 75, preferably 25 to 70, and more preferably 30 to 65.

[0155] "z" is the number of AA units of the pAA sub-block contained in the pAA block. Preferably, "z" is a number in the range of 0 to 120, preferably 0 to 110, preferably 5 to 100, preferably 9 to 95, preferably 10 to 90, preferably 15 to 85, preferably 18 to 80, preferably 20 to 75, preferably 25 to 70, and more preferably 30 to 65.

[0156] Advantageously, y is a number in the range of 5 to 50, and z is a number in the range of 0 to 50. Preferably, y is in the range of 9 to 45, and z is in the range of 0 to 45. Preferably, y is in the range of 9 to 40, and z is in the range of 5 to 45. Preferably, y is in the range of 10 to 40, and z is in the range of 9 to 45. Preferably, y is in the range of 10 to 40, and z is in the range of 10 to 40.

[0157] In a preferred embodiment, y or z is 0. Preferably, z is 0 and y ranges from 8 to 120, preferably from 9 to 110, preferably from 12 to 100, preferably from 15 to 95. In a preferred embodiment, z is 0 and y is an integer in the range of 8 to 50, preferably from 9 to 45, preferably from 12 to 40, more preferably from 15 to 35. In a preferred embodiment, z is 0 and y is an integer in the range of 50 to 120, preferably from 55 to 110, preferably from 60 to 100, more preferably from 65 to 95.

[0158] Advantageously, the pAA block has an H hydrophobicity coefficient of -0.50 or more, preferably -0.25 or more, preferably 0.00 or more, preferably 0.50 or more, more preferably 0.80 or more. Typically, the pAA block has an H coefficient in the range of -0.50 to 20.00, preferably -0.25 to 18.00, preferably 0.00 to 15.00, more preferably 0.50 to 10.00, or even 0.80 to 6.00. The H hydrophobicity coefficient of the pAA block is: - When one of y or z is 0, it is determined by the formula E1 defined above. When z = 0, "n" corresponds to "y", or when y = 0, "n" corresponds to "z"; or - When both y and z are different from 0, it is determined by E2 defined above.

[0159] In formulas (I) and (II), the side chains of the AA units of the pAA block are R y groups and R z groups. The R y group and the R z group are the side chains of the AA units defined above. According to the present invention, R y and R z are not H.

[0160] Advantageously, the units carrying the R y group and the R z group of the pAA block are independently selected from natural or non-natural amino acids as long as the side chain of the hydrophobic pAA block is hydrophobic.

[0161] Preferably, R y group and / or R z group carry at least one aryl group and / or at least one heteroaryl group. The aryl group and / or heteroaryl group may be present in the amino acid and / or in the protecting group of the AA. For example, R y group and / or R z group may be the side chain of glutamic acid protected by a benzyl group, i.e., the side chain of D-glutamic acid γ-benzyl.

[0162] The functional group of the side chain of the AA can be protected by various protecting groups disclosed above. Preferably, the protecting group contains at least one aryl group and / or at least one heteroaryl group.

[0163] R y group and R z The alpha-carbon of the AA unit carrying the group can have a D-configuration or an L-configuration. In the present invention, when R y or R z is shown as L- or D-, preferably L-AA or D-AA, it means that the carbon carrying the R y group or R z group is in the L-configuration or the D-configuration. Preferably, when R y or R z is shown as L-AA or D-AA, it means that R y or R z is in the L-configuration or the D-configuration of the corresponding AA.

[0164] Advantageously, the alpha-carbon carrying R y and R z is independently in the D-configuration or the L-configuration. Preferably, the alpha-carbon carrying R y and R z has different configurations. Preferably, R yis the side chain of a hydrophobic L-AA, R z is the side chain of a hydrophobic D-AA. Preferably, R y is the side chain of a hydrophobic D-AA, R z is the side chain of a hydrophobic L-AA.

[0165] Preferably, R y and R z at least one of them is the side chain of an AA having at least one aryl group and / or at least one heteroaryl group. In particular, both R y and R z are the side chains of an AA having at least one aryl group and / or at least one heteroaryl group.

[0166] Preferably, R y and R z are independently selected from -CH3, -CH(CH3)2, -(CH2)3-CH3, -CH2-CH(CH3)2, -CH(CH3)-CH2-CH3, -CH2-CH2-S-CH3, -CH2-C6H5, -CH2-(1H-indol-3-yl), -CH2-CH2-CH2-, -CH2-4-(OH)C6H4, -CH2-C(O)-NH-C(C6H5)3, -CH2-C(O)-OCH2-C6H5, -CH2-S-CH2-C6H5, -C6H 11 , -CH2-CH2-C(O)-O-CH2-C6H5, -CH2-CH2-C(O)-O-C(CH3)3, -(CH2)4-NH-C(O)-CF3, -CH2-O-CH2-C6H5, -CH2-4-(acetyl)-C6H5, and -CH2-C6H4-O-CH2-C6H5.

[0167] Preferably, R y and R z are independently selected from -CH2-CH(CH3)2, -CH2-C6H5, -CH2-4-(OH)C6H4, -CH2-CH2-C(O)-O-CH2-C6H5, -CH2-CH2-C(O)-O-C(CH3)3, and -C6H 11 .

[0168] Preferably, R y and R z are independently selected from -CH2-C6H5, -CH2-4-(OH)C6H4, -CH2-CH2-C(O)-O-CH2-C6H5, -CH2-C(O)-NH-C(C6H5)3, -CH2-C(O)-OCH2-C6H5, -CH2-S-CH2-C6H5, -CH2-O-CH2-C6H5, -CH2-4-(acetyl)-C6H5, and -CH2-C6H4-O-CH2-C6H5.

[0169] Preferably, R y and R z are independently selected from the side chains of L-leucine, L-phenylalanine, L-tyrosine, L-glutamic acid γ-benzyl, L-glutamic acid γ-tert-butyl, L-cyclohexylglycine, D-leucine, D-phenylalanine, D-cyclohexylglycine, D-tyrosine, D-glutamic acid γ-benzyl, and D-glutamic acid γ-tert-butyl.

[0170] In some embodiments, each of R y is independently the side chain of L-leucine, L-phenylalanine, L-tyrosine, L-glutamic acid γ-benzyl, or L-glutamic acid γ-tert-butyl. In some embodiments, each of R z is independently the side chain of D-leucine, D-phenylalanine, D-cyclohexylglycine, D-tyrosine, D-glutamic acid γ-benzyl, or D-glutamic acid γ-tert-butyl. Preferably, each of R y and R z is independently -CH2-CH2-C(O)-O-CH2-C6H5, -CH2-CH2-C(O)-O-C(CH3)3. Preferably, each of R y is independently the side chain of L-glutamic acid γ-benzyl, or L-glutamic acid γ-tert-butyl. Preferably, each of R z is independently the side chain of D-glutamic acid γ-benzyl, or D-glutamic acid γ-tert-butyl.

[0171] Preferably, R2 is a nitrogen protecting group. The nitrogen protecting group can be selected from any group well-known in the art. The nitrogen protecting group includes, but is not limited to, tert-butyloxycarbonylamino (-NHBOC), ethyloxycarbonylamino, methyloxycarbonylamino, trichloroethyloxycarbonylamino, allyloxycarbonylamino (-NHAlloc), benzyloxycarbonylamino (-NHCbz), allylamino, benzylamino (-NHBn), fluorenylmethylcarbonyl (-NHFmoc), formamide, acetamide, chloroacetamide, dichloroacetamide, trichloroacetamide, phenylacetamide, trifluoroacetamide, benzamide, tert-butyldiphenylsilyl, and the like, including arylalkylamines, carbamates, allylamines, amides, and their derivatives.

[0172] Preferably, R 1a and R 1b are independently selected from H, (C1-C 10 ) alkyl, (C2-C 10 ) alkene, (C2-C 10 ) alkyne, (C3-C 10 ) cycloalkyl, (C5-C 10 ) aryl, (C4-C 10 ) heteroaryl. Preferably, R 1a and R 1b are independently selected from H, (C1-C6) alkyl, (C2-C8) alkene, (C2-C 10 ) alkyne, (C3-C 10 ) cycloalkyl, (C5 or C6) aryl, (C4 or C5) heteroaryl. More preferably, R 1a and R 1b are independently selected from H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and phenyl and / or benzyl groups which may be substituted with halogen, -CH3, -CF3, -OCH3, OH.

[0173] Preferably, R 1a is H, R 1b is neopentyl, and R 2 is selected from H or -C(O)CH3.

[0174] Advantageously, the NR 1a R 1b group is a residue derived from a polymerization initiator attached to the first block.

[0175] Advantageously, the R 2 group is a residue derived from a terminator or capping agent attached to the last block formed during the synthesis of the linear copolymer.

[0176] According to a preferred embodiment of the present invention, when the first block is pSa and the last block is pAA, the linear copolymer is defined by general formula I, wherein, the R 1a group and the R 1b group are independently selected from H, an alkyl group, or an aryl group, the R 2 group is selected from H, an alkyl group, and the R 3 OC(O)-, R 3 C(O)-, R 3 SO2- selected from the groups so selected, wherein R 3 is (C1-C 10 ) alkyl, (C2-C 10 ) alkene, (C2-C 10 ) alkyne, (C3-C 10 ) cycloalkyl, (C5-C 10 ) aryl, and (C4-C 10 ) heteroaryl selected.

[0177] According to a preferred embodiment of the present invention, when the first block is pAA and the last block is pSar, the linear copolymer is defined by general formula II, wherein, the R 1a group and the R 1bThe group is independently selected from H, an alkyl group, or an aryl group. R 2 The group is H, an alkyl group, and R 3 OC(O)-, R 3 C(O)-, R 3 selected from groups selected from SO2-. wherein R 3 is (C1-C 10 ) alkyl, (C2-C 10 ) alkene, (C2-C 10 ) alkyne, (C3-C 10 ) cycloalkyl, (C5-C 10 ) aryl, and (C4-C 10 ) heteroaryl.

[0178] Preferably, the R group in formula I or formula II 2 is a residue derived from a capping agent selected from an alkyl group and groups selected from R 3 OC(O)-, R 3 C(O)-, R 3 SO2-. Preferably, R 3 is selected from H, (C1-C6) alkyl, (C2-C8) alkene, (C2-C 10 ) alkyne, (C3-C 10 ) cycloalkyl, (C5 or C6) aryl, (C4 or C5) heteroaryl. More preferably, R 3 is selected from methyl, ethyl, propyl, butyl, trifluoromethyl.

[0179] Preferably, the copolymer is selected from copolymer C1 to copolymer C12 represented by formula (I') or formula (II').

[0180]

Chemical formula

[0181] (wherein R 1a is H, and R 1bis -CH2-C(CH3)3, R 2 is H or CH3C(O)-, x and "y + z" have various values according to the copolymers according to the invention described in the following examples.

[0182] Method for preparing a copolymer The present invention also relates to a method for preparing a linear copolymer. Preferably, the linear copolymer is synthesized by polymerization of a sarcosine derivative and an amino acid derivative. Preferably, the copolymer is synthesized by ring-opening polymerization in which the Sar derivative and the AA derivative are respectively the N-carboxy anhydride (NCA) or thio-carboxy anhydride (NTA) of the corresponding structural units.

[0183] Advantageously, the synthesis of the linear copolymers according to the invention having a limited number of Sar and / or AA structural units is easy compared to the prior art and is thus not very costly. The industrial scale-up of the preparation of the linear copolymers according to the invention is also easy.

[0184] According to the present invention, the Sar derivative and the AA derivative correspond to the compounds respectively represented by the following formula III and formula IV.

[0185]

Chemical formula

[0186] (In the formula, A is O or S; R y , R z are as described above)

[0187] The compounds of formula III and formula IV, also referred to as derivatives, are NCA when A is O and NTA when A is S.

[0188] The compound of formula III may be a monomer used to prepare the pSar block. The compound of formula III is also denoted as NCA / NTA of sarcosine or sarcosine NCA / NTA or Sar NCA / NTA.

[0189] The compound of formula IV may be a monomer used to prepare the pAA block. When compound IV is used to prepare the units of the pAA block having y superscript, it is denoted as IV y as shown. Similarly, compound IV z is used to prepare the units of the pAA block having z superscript. R y and R z are as defined above. It is also denoted as NCA / NTA of amino acid or amino acid NCA / NTA or AA NCA / NTA.

[0190] The linear copolymers of the present invention are - step a) of forming a first block by ring-opening polymerization by reacting a first derivative in the presence of a polymerization initiator, wherein the first derivative is selected from compound III or at least one compound IV, step a), - optional step b) of isolating the first block formed in step a), - step c) of forming a final block by mixing a second derivative selected from compound III or at least one compound IV with the first block obtained in step a) or the first block isolated in optional step b), wherein the first derivative and the second derivative are different and one of them is compound III, step c), - step d) of recovering the copolymer and can be prepared by a method comprising.

[0191] Advantageously, step d) of recovering the linear copolymer of the present invention includes the isolation and purification of the copolymer obtained from step c). Preferably, step d) of recovering is carried out after the consumption of the derivative introduced in step c).

[0192] Advantageously, when the last block is formed after adding the derivative into the mixture obtained in step a), step c) is carried out after the consumption of the derivative introduced in step a).

[0193] Advantageously, derivatives other than sarcosine introduced in step a) or step c) are selected from two AAs having formula IV. Preferably, one of the amino acids has formula IV containing an R y group, and the other AA has formula IV y containing an R z group. The carbon atoms carrying R z and R y and R z can be in D-configuration or L-configuration.

[0194] Advantageously, the copolymer can be prepared by a one-pot method in which the first block formed in step a) is not isolated in an optional step b). In this embodiment, the last block is formed after the consumption of the derivative introduced in step a) by directly mixing the second derivative into the mixture obtained in step a).

[0195] In one embodiment, the derivative introduced in step a) is compound III, and the derivative introduced in step c) is compound IV.

[0196] In another embodiment, the derivative introduced in step a) is compound IV, and the derivative introduced in step c) is compound III.

[0197] Preferably, step a) and / or step c) is carried out under reduced pressure or under atmospheric pressure.

[0198] Preferably, step a) and / or step c) is carried out at a temperature in the range of 0 to 80 °C, preferably 5 to 60 °C, preferably 10 to 50 °C, preferably 15 to 40 °C, preferably 20 to 30 °C, more preferably 22 to 28 °C.

[0199] Advantageously, step a) and / or step c) is carried out in a solvent selected from N,N-dimethylformamide, tetrahydrofuran, dimethyl sulfoxide, water, acetonitrile, ethyl acetate. Preferably, the solvent is N,N-dimethylformamide.

[0200] Preferably, the solvent in step a) is the same as the solvent in step c).

[0201] In a preferred embodiment, the derivative is introduced as a solid powder in step a) and / or step c).

[0202] In some embodiments, the derivative is introduced as a solution in a solvent in step a) and / or step c). Preferably, the solvent of the derivative solution is the same as the solvent used in the reaction.

[0203] Preferably, the polymerization initiator is preferably an amine having the formula (R 1a )(R 1b )NH, wherein R 1a and R 1b are as defined above.

[0204] Preferably, the molar ratio of the first derivative to the polymerization initiator is in the range of 5 to 120, preferably 20 to 110, preferably 30 to 100, more preferably 40 to 95.

[0205] Advantageously, the method for preparing the copolymer can also include a stopping step carried out before step d) after the consumption of the derivative introduced in step c). Preferably, the stopping step corresponds to the step of consuming all of the derivative introduced in step c). Advantageously, the stopping step can be carried out using a terminating agent well-known in the art. Preferably, the stopping step is carried out by protonation. Then, R 2 is preferably H. Optionally, the terminating agent can be selected from acids such as water, acetic acid, triflic acid, or trifluoroacetic acid.

[0206] Preferably, the method of preparation includes a capping step carried out by the addition of a capping agent and optionally any other reagents required for the reaction, before or after step d). When the capping step is before step d), the introduction of the capping agent is carried out after the consumption of the derivative introduced in step c). In this embodiment, the capping step can be carried out after the stopping step. In this embodiment, the capping agent can also be the terminating agent. Then, the stopping step and the capping step are carried out in a single step.

[0207] When the capping step is after step d), the capping step is carried out by mixing the copolymer with the capping agent in the presence of the solvent defined above.

[0208] In any case, preferably, the capping step is carried out at a temperature in the range of 0 to 80 °C, preferably 5 to 60 °C, preferably 10 to 50 °C, more preferably 15 to 40 °C, preferably 20 to 30 °C, more preferably 22 to 28 °C.

[0209] Advantageously, the capping step is carried out at the same temperature as step a) and / or step c).

[0210] The capping step is preferably carried out by the addition of a capping agent having the formula R 2 X. R 2 is as defined above, and X is a leaving group. Preferably, X is a leaving group well-known to those skilled in the art. Preferably, X is selected from Cl-, I-, Br-, CF3C(O)-, CH3C(O)-.

[0211] Nanoparticle Another aspect of the present invention is directed to nanoparticles comprising the linear copolymer defined above. The nanoparticles are formed by self-assembly of the linear copolymer according to the present invention.

[0212] Advantageously, the nanoparticles comprise a linear copolymer and at least one active compound.

[0213] According to one aspect of the present invention, the nanoparticles according to the present invention have a hydrodynamic diameter D h that is smaller than 900 nanometers (nm), preferably smaller than 600 nm, preferably in the range of 1 to 600 nm, preferably 2 to 500 nm, preferably 5 to 300 nm, preferably 8 to 200 nm, more preferably 10 to 110 nm. h

[0214] Preferably, the nanoparticles have a polydispersity index PDI lower than 0.7, preferably in the range of 0.02 to 0.70, preferably 0.05 to 0.60, more preferably 0.10 to 0.50.

[0215] Advantageously, the active compound can be bound by non-covalent interactions with the nanoparticles. Preferably, the active compound can be bound within the nanoparticles or adsorbed on the surface of the nanoparticles by non-covalent interactions. Preferably, the active compound is bound to the nanoparticles by hydrophobic interactions.

[0216] ​Preferably, the active compound is hydrophobic. The compound may be an active pharmaceutical ingredient (API) and a nucleic acid, such as siRNA, miRNA.

[0217] According to a preferred embodiment, the nanoparticles contain at least two active compounds, preferably at least two APIs.

[0218] Preferably, the hydrophobic compound is filled within the nanoparticles.

[0219] The hydrophobic compound, preferably the hydrophobic API, is a compound having a water solubility of less than 10 g / L.

[0220] Nanoparticles containing a copolymer and an API are referred to as drug-loaded nanoparticles.

[0221] Advantageously, the drug-loaded nanoparticles according to the present invention have the following advantages: - Preventing or delaying API degradation, - Controlling API release, - Improving API bioavailability, and - Enhancing the absorption of the API into tumor tissue by passive targeting via enhanced permeability and retention (EPR effect) for anti-tumor applications and having at least one of them.

[0222] Preferably, the API is selected to be suitable for targeting a disease selected by those skilled in the art. Examples of APIs include anti-cancer agents, antibacterial agents, antiviral agents, anti-inflammatory agents, immunosuppressive drugs, steroid drugs, hormone drugs, and angiogenesis inhibitors. These drug molecules may be used alone or in combination of two or more of them.

[0223] Preferably, the API is selected from 10,11-methylenedioxycamptothecin, 10-hydroxy-7-ethylcamptothecin (SN38), 2-chloroadenosyltrimethoprim, 5-azacytidine, 5-azadeoxycytidine, 5'-deoxyfluorouridine, 5-fluorouracil (5-FU), 6-mercaptopurine, 6-thioguanine, 9-aminocamptothecin, 9-nitrocamptothecin, acyclovir, aldesleukin, allopurinol, amantadine, amiodarone, aminopterin, amsacrine, asparaginase, bleomycin, budesonide, busulfan, camptothecin, capecitabine, carboplatin, celecoxib, CI-973, cisplatin, cladribine, CPT-11, curcumin, cyclophosphamide, cyclosporine, cytarabine, dacarbazine, daunorubicin, deoxycytidine, docetaxel, doxorubicin, eniluracil, epirubicin, epothilones A - E, etoposide, etoposide phosphate, fludarabine, ganciclovir, gemcitabine (Gemzar), ifosfamide mephosfamide, irinotecan, JM-216, carzelesin, carzelesin, lamivudine, L-phenylalanine mustard, methotrexate, methylene-10-deazaminopterin (MDAM), mitomycin, mitoxantrone, ormaplatin, oxaliplatin, paclitaxel, perfosfamide, picoplatin, platinum-DACH, procarbazine, rapamycin, resveratrol, rimantadine, satraplatin, semustine, tamoxifen, TAS 103, temozolomide, tetraplatin, tomudex, topotecan, tretinoin, trofosfamide carmustine, UFT, valacyclovir, vinblastine, vincristine, vindesine, vinorelbine, zidovudine, and combinations thereof or pharmaceutically acceptable salts thereof.

[0224] One aspect of the present invention is preferably the use of drug-loaded nanoparticles as a pharmaceutical in cancer treatment. A preferred aspect of the present invention is a method for treating or preventing a disease or condition such as cancer, including administering the nanoparticles of the present invention to a patient in need thereof. Another preferred aspect of the present invention is the use of the nanoparticles according to the present invention for the manufacture of a pharmaceutical for therapeutic use, preferably for cancer treatment. In particular, the hydrophobic API may be a cytotoxic agent such as a taxoid, more particularly paclitaxel.

[0225] Preferably, the hydrophobic API is advantageously, more preferably, an anticancer drug selected from paclitaxel (Taxol), doxorubicin, daunorubicin, vinblastine, docetaxel (Taxotere), 10-hydroxy-7-ethylcamptothecin (SN38).

[0226] Advantageously, the nanoparticles improve the solubility of the hydrophobic API. The aqueous solubility represents the concentration at which a compound can dissolve in water. For the hydrophobic API loaded in the nanoparticles, the aqueous solubility of the API is considered to be the API concentration, [API], in the nanoparticle suspension, technically not in solution. Advantageously, the nanoparticles improve the aqueous solubility of the hydrophobic API by more than 100-fold, preferably more than 200-fold, preferably more than 500-fold, preferably more than 1000-fold, preferably more than 2000-fold, more preferably more than 3000-fold.

[0227] Preferably, the API in the API-loaded nanoparticles has an aqueous solubility indicated as [API] of 0.2 to 2.0 g / L, preferably 0.3 to 1.5 g / L, preferably 0.4 to 1.5 g / L, more preferably 0.5 to 1.5 g / L.

[0228] Advantageously, a high value of [API] enables a smaller volume of the particles to be required for being effective against the target of the API such as a tumor.

[0229] Method for preparing nanoparticles The copolymer according to the present invention can spontaneously self - assemble into nanoparticles in an aqueous solution, and can represent a corona formed by the pSar block and a core formed by the pAA block.

[0230] The present invention relates to a method for preparing nanoparticles containing the above - mentioned linear copolymer. Preferably, the nanoparticles are prepared by the following steps: - Preparing an organic solution containing an organic solvent and the linear copolymer of the present invention, - Then mixing the organic solution with an aqueous solution, - Then removing the organic solvent by a method including these steps.

[0231] The organic solvent is preferably a polar aprotic solvent.

[0232] The present invention also targets a method for preparing nanoparticles containing a linear copolymer and an active compound, where the copolymer and the active compound are as described above.

[0233] In the following, the method for preparing nanoparticles is described for a hydrophobic API, but the method is also applicable to any hydrophobic compound as described above.

[0234] Advantageously, when the formation of nanoparticles is carried out in the presence of a hydrophobic API, it enables the encapsulation of the API in the hydrophobic core of the nanoparticles.

[0235] The encapsulation of the hydrophobic API by the nanoparticles can occur by a method including the following steps: - Preparing an organic solution containing an organic solvent, the above - mentioned copolymer, and at least one of the above - mentioned hydrophobic APIs, - Mixing the organic solution with an aqueous solution, - Optionally, removing the organic solvent, - Recovering the nanoparticles by a method including these steps.

[0236] A preferred method for preparing the nanoparticles is - step i) of mixing the hydrophobic API and the copolymer according to the invention in an organic solvent to obtain an organic solution, - step ii) of mixing the solution obtained in step i) with an aqueous solution while stirring to obtain nanoparticles, - optional step iii) of filtering the nanoparticles, - optional step iv) of purifying, for example, by gel filtration chromatography, - optional step v) of filtering the nanoparticles, - optional step vi) of freezing or freeze-drying, - step vii) of recovering the nanoparticles including.

[0237] In one embodiment, step ii) is carried out by adding the organic solution obtained in step i) into an aqueous solution. In another embodiment, step ii) is carried out by adding an aqueous solution into the solution obtained in step i).

[0238] Preferably, the organic solvent is a polar aprotic solvent. Preferably, the polar aprotic solvent is selected from N,N-dimethylformamide and N,N-dimethylacetamide.

[0239] In a preferred embodiment, the solvent used in step ii) is the same as the solvent used in step a) and / or step c) of the preparation of the copolymer. This embodiment facilitates the purification of the copolymer and limits the potential influence of residual solvents resulting from the preparation of the copolymer by self-assembly of the nanoparticles. Preferably, the solvent is N,N-dimethylformamide.

[0240] Preferably, the aqueous solution is water or contains water as the main solvent.

[0241] In a preferred embodiment where the nanoparticles are suitable as a pharmaceutical dosage form, the aqueous solution in step ii) can further contain an antifreeze agent and / or a buffer.

[0242] The antifreeze agent prevents the damage or change of other compounds related to freezing or lyophilization and enables reaching the physiological osmolarity. The antifreeze agents include, but are not limited to: monosaccharides, disaccharides, polyhydric alcohols, amino acids, glycine, polyvinylpyrrolidone, polyethylene glycol, mannitol, sorbitol, sucrose, glucose, raffinose, sucralose, lactose, trehalose, dextran, and dextrose. Preferably, the antifreeze agent is trehalose.

[0243] The buffer enables reaching the physiological pH and also affects the osmolarity. The buffers include, but are not limited to: phosphate buffer, phosphate buffered saline (PBS), histidine buffer, or HEPES buffer.

[0244] Advantageously, the mixing conditions in step ii) are adjusted to optimize the resulting nanoparticles. The said conditions are, for example, the nature of mixing (magnetic stirring, homogenizer), mixing time, the order of adding one solution to the other, or the flow rate of addition.

[0245] To initiate the purification process and protect the lifespan of the column used in optional step iv), optional step iii) can be carried out to remove the unfilled (free) API from the suspension.

[0246] Optional step iv) can be carried out to obtain a nanoparticle suspension in an aqueous solution by removing the polar protic solvent and the unfilled API. When the aqueous solution is water, step iv) enables obtaining a nanoparticle suspension in a pure aqueous solution.

[0247] Preferably, the filtration in step v) is carried out using a sterilizing filter of 0.2 μm, 0.22 μm, or 0.45 μm to sterilize the nanoparticles.

[0248] Advantageously, the nanoparticles according to the invention have a filling efficiency, LE, which is higher than 20%, preferably higher than 30%, preferably higher than 40%, preferably higher than 45%, preferably higher than 50%, preferably higher than 55%, preferably higher than 60%, preferably higher than 65%, more preferably higher than 70%. Advantageously, the filling efficiency is from 40 to 99%, preferably from 50 to 96%, preferably from 60 to 95%, more preferably from 70 to 94%.

[0249] The filling efficiency is the weight ratio of the mass of the API filled in the nanoparticles to the mass of the supplied API.

[0250] Advantageously, the feed weight ratio, FWR, ranges from 1 to 100%, preferably from 2 to 80%, preferably from 3 to 60%, preferably from 4 to 50%, preferably from 5 to 40%, more preferably from 10 to 30%. The FWR is the weight ratio of the mass of the supplied API to the mass of the supplied copolymer.

Examples

[0251] The following examples are provided so that the disclosure described herein can be more fully understood. These examples are for illustrative purposes only and are not to be considered in any way as limiting the present disclosure.

[0252] In the following examples, the copolymer according to the invention comprises a block of poly(sarcosine) and a block derived from L-glutamic acid γ-benzyl and / or D-glutamic acid γ-benzyl.

[0253] Materials and methods Paclitaxel was supplied by Key Organics. All organic solvents (HPLC grade) were provided by VWR. Water was of ultrapure water grade. Unless otherwise indicated, the temperature was room temperature (22 - 28 °C).

[0254] FTIR spectroscopy NCA polymerization was monitored by Fourier transform infrared (FTIR) spectroscopy using a Thermo Scientific Nicolet iS5 spectrometer equipped with an ID7 ATR module. The data were processed using OMNIC 9.7 software. The polymerization was stopped when the carbonyl bands associated with the NCA at 1850 cm -1 and 1778 cm -1 disappeared corresponding to complete NCA consumption.

[0255] Proton NMR Proton nuclear magnetic resonance ( 1 1H NMR) was performed using an 80 MHz MAGRITEK Spinsolve 80 Carbon with the following parameters: NS = 64, repetition time = 10 - 30 s, pulse angle = 90 by dissolving the product in deuterated dimethyl sulfoxide (d6-DMSO) at a concentration of 20 - 50 g / L. The data were processed using SpinSolve software and MestReNova software.

[0256] SEC Size exclusion chromatography (SEC) analysis was performed on an Agilent 1260 LC equipped with three column sets of a diode array detector (UV-Vis), a differential refractive index detector (dRI), and PSS GRAM analytical columns (100 Å, 8 × 300 mm, 10 μm; 100 Å, 8 × 300 mm, 10 μm; 1000 Å, 8 × 300 mm, 10 μm) having an exclusion limit of 100 - 1000000 g / mol in DMF containing 0.45% w / v LiBr. The analysis was carried out on samples prepared in DMF containing 0.45% w / v LiBr using DMF containing 0.45% w / v LiBr as the eluent (1 mL / min). The data was acquired and processed with OpenLAB Chemstation software.

[0257] SEC for copolymer characterization For the number average molar mass (M n ) and dispersity of polymers and copolymers

[0258] [Number]

[0259] To determine them, the analysis was carried out on polymer samples prepared at 4 g / L. An EasiVial kit of polystyrene from Agilent was used as the standard (266 - 66000 g / mol). The data was further processed with Cirrus add-on.

[0260] SEC for nanoparticle characterization To determine the copolymer concentration ([C in NP]) in PTX-loaded nanoparticles, samples of each NP with a volume of 400 μL were dried using a centrifugal evaporator (SP Genevac EZ2, automatic water evaporation program). The samples injected into SEC were prepared by dissolving the dried samples in 1 mL of DMF containing 0.45% w / v LiBr, so it was a 2.5-fold dilution.

[0261] Standard curves of DMF containing 0.45% w / v LiBr were prepared at polymer concentrations ([C]) of 1 - 4 g / L for each copolymer. Linear regression of the area obtained for the RI signal of the polymer vs. [C] was plotted for each polymer to obtain the standard curve equation.

[0262] For each formulated sample, [C in NP] was then determined by multiplying the dilution factor using the obtained peak area and the appropriate standard curve equation.

[0263] The loading content (LC) of PTX - loaded NPs was calculated as the ratio of the mass of PTX recovered at the final stage of NP preparation (m(PTX in NP) obtained by UPLC) to the mass of NPs; the mass of NPs was the sum of the mass of the copolymer (obtained using [C in NP] by SEC) and m(PTX in NP).

[0264] DLS DLS measurements were performed at 25 °C and a scattering angle of 174.8° using a Zetasizer Pro (Malvern Panalytical) equipped with a He - Ne laser (633 nm). The software used was ZS Explorer. A low - volume plastic cell with an optical path length of 10 mm was filled with 70 μL of the sample. The viscosity of the dispersant was collected according to the solvent or mixture of solvents used. Data were acquired in three different measurements with automatic optimization of the number of runs and run - time length per measurement. Results are presented as the average of these three measurements. The D h of the object is the intensity average of each population. PDI is calculated from the autocorrelation function using the cumulant method.

[0265] UPLC Ultra - performance liquid chromatography (UPLC) measurements were performed on a Waters Acquity UPLC H - class equipped with a reversed - phase column (Acquity BEH, C18, 130 Å, 50 mm×2.1 mm×1.7 μm, Waters) and a Waters diode - array detector (DAD) Acquity eλ. Data were acquired and processed with Empower 3 software. Gradient elution was performed with two solvents: Solvent A was water containing 0.05% (v / v) trifluoroacetic acid (TFA), and Solvent B was acetonitrile (ACN) containing 0.05% (v / v) TFA. The column was equilibrated with an 80:20 A:B mixture for at least 30 minutes. The sequence time length was 8 minutes for the following gradient of Solvent A:Solvent B: 80:20 from 0 - 3 minutes, 5:95 from 3 - 5 minutes, 80:20 from 5 - 8 minutes. The eluent was degassed mechanically. The flow rate was 0.5 mL / min. The column temperature was 35 °C. The injected volume was 3 μL. The UV detector was set at 254 nm. The typical retention time of PTX was 2.24 minutes.

[0266] The loading efficiency (LE) of PTX - loaded NPs was determined by UPLC. The injected sample was prepared by dissolving 90 μL of NPs in 910 μL of ACN:DMF 90 / 10 v / v, so it was a 11.1 - fold dilution.

[0267] A standard curve of ACN:(H2O / DMF 90 / 10) 90:10 v / v was prepared at PTX concentrations ([PTX]) of 5 - 20 μg / mL. A linear regression of area vs. [PTX] at 254 nm was plotted to obtain the standard curve equation.

[0268] For each formulated sample, the PTX concentration in the nanoparticles ([PTX in NP]) was determined using the obtained peak area and the standard curve equation, and then multiplied by the dilution factor.

[0269] LE was calculated as the ratio of m(PTX in NP) (obtained using [PTX in NP]) divided by the mass of PTX initially supplied in the preparation of the NPs.

[0270] HS-GC Headspace gas chromatography (HS-GC) was used to fractionate the DMF content, which is a residual solvent in the formulation. HS-GC was performed on an Agilent 7890B GC system equipped with a split / splitless injector, a flame ionization detector (FID), and an Agilent 7697A autosampler, using a CP Sil 5CB column (length 50 m, diameter 0.32 mm, film thickness 5 μm). A known sample volume was introduced into a 20 mL crimp vial and dissolved using several milliliters of a low volatility solvent (water, DMSO, or NMP). The vial was crimped and incubated to reach an equilibrium state of the residual solvent concentration between the liquid and gas phases. Subsequently, the headspace of the vial was injected into the GC system by a split injector, and the residual solvent was detected by the FID. The data were acquired and processed using OpenLAB Chemstation software.

[0271] Abbreviations The following abbreviations were used in the examples.

[0272]

Table A

[0273] In the following examples, according to the above method, - The values of x, y + z and f(pSar) for each copolymer were determined by 1 1H NMR; - M n and

[0274]

Number

[0275] Example 1: Preparation of the pSar block Sar NCA (4.34.10 -2 mol, 75 eq) was dissolved in dehydrated DMF at room temperature, followed by the addition of neopentylamine (73 μL, 6.20.10 -4 mol, 1 eq) as the initiator. The reaction mixture was stirred at room temperature, and after the evolution of CO2 ceased, the completion of the reaction was confirmed by FTIR spectroscopy.

[0276] Precipitation of the polymer was carried out by pouring the reaction mixture into 300 mL of ethyl acetate with vigorous stirring at room temperature. After filtration, the product was slurried again with 2 × 100 mL of ethyl acetate and then dried under vacuum.

[0277] pSar block S1 with x = 75 was obtained in a yield of 70%, M n 4570 g / mol, and

[0278]

Number

[0279] 1.16.

[0280] pSar block S2 was prepared according to the same procedure except that 28 eq of Sar NCA (1.62.10 -2 mol) was used. pSar block S2 with x = 29 was obtained in a yield of 85%, M n 2200 g / mol, and

[0281]

Number

[0282] 1.22.

[0283] Example 2: Preparation of the copolymer of formula I Procedure for two-step synthesis The pSar block S1 synthesized in Example 1 (M n = 4570 g / mol, 1.31×10 -4 mol, 1.0 eq) was dissolved in dehydrated DMF (17 mL) at room temperature. A mixture of L-GluOBzl NCA (6.42×10 -3 mol, 49 eq) powder and D-GluOBzl NCA (6.42×10 -3 mol, 49 eq) powder was added to the reaction medium. The reaction mixture was stirred at 5 °C, and after the evolution of CO2 ended, the completion of the reaction was confirmed by FTIR spectroscopy.

[0284] Precipitation of the copolymer was carried out by pouring the reaction mixture into 200 mL of MTBE with vigorous stirring at room temperature. After filtration, the product was slurried again with 2×100 mL of MTBE and then dried under vacuum. Copolymer 1 was obtained in a yield of 76%.

[0285] Copolymers C2 to C5 according to the present invention having the pSar blocks and amounts shown in Table 1 were prepared according to the same procedure as C1.

[0286]

Table 1

[0287] Copolymers C1 to C5 according to the present invention have the properties shown in Table 2.

[0288]

Table 2

[0289] Procedure for "one-pot" synthesis Sar NCA (2.78×10 -2Sarcosine (70 eq) was dissolved in dehydrated DMF at room temperature, and then neopentylamine (1 eq) was added as an initiator. The reaction was stirred at room temperature, and after the evolution of CO2 ceased, the completion of the reaction was confirmed by FTIR spectroscopy.

[0290] To the reaction medium containing pSar, pre-weighed and mixed, L-GluOBzl NCA (4.52×10 -3 mol, 12 eq) and D-GluOBzl NCA (4.52×10 -3 mol, 12 eq) were added. After 20 h at room temperature, the complete consumption of NCA was confirmed by FTIR spectroscopy.

[0291] Precipitation of the copolymer was carried out by pouring the reaction mixture into 300 mL of MTBE with vigorous stirring at room temperature. After filtration, the product was slurried again with 2×100 mL of MTBE and then dried under vacuum. Copolymer 6 was obtained in 54% yield.

[0292] The properties of copolymer C6 are shown in Table 3.

[0293]

Table 3

[0294] Example 3: Preparation of the copolymer of formula II Procedure for "reverse one-pot" synthesis L-GluOBzl NCA (11 eq) and D-GluOBzl (11 eq) were dissolved in 40 mL of dehydrated DMF at room temperature, and then neopentylamine (58.5 μL, 1 eq) was added as an initiator. The reaction mixture was stirred at room temperature, and after the evolution of CO2 ceased, the completion of the reaction was confirmed by FTIR spectroscopy.

[0295] Subsequently, Sar NCA (70 eq) was added to the reaction mixture. Again, the reaction mixture was stirred at room temperature, and after the evolution of CO2 ceased, the completion of the reaction was confirmed by FTIR spectroscopy. Precipitation of the copolymer was carried out by pouring the reaction mixture into 200 mL of MTBE with vigorous stirring at room temperature. After filtration, the product was slurried again with 2 × 100 mL of MTBE and then dried under vacuum. Copolymer C7 was obtained in 89% yield.

[0296] Copolymer C8 was prepared according to the same procedure as C7 using L-GluOBzl NCA (24 eq) without using D-GluOBzl NCA. Copolymer C8 was obtained in 91% yield.

[0297] Copolymer C9 was prepared according to the same procedure as C7 using D-GluOBzl NCA (24 eq) without using L-GluOBzl NCA. Copolymer C9 was obtained in 85% yield.

[0298] The properties of Copolymer C7 - Copolymer C9 are shown in Table 4.

[0299]

Table 4

[0300] Procedure for the capping step Copolymer C8 was dissolved in 10 mL of dehydrated DMF at room temperature, followed by the addition of DMAP (16 mg, 1.3×10 -4 mol, 1 eq) and NMM (162 μL, 1.43×10 -3 mol, 11 eq). After complete dissolution, acetic anhydride (123 μL, 1.3×10 -3 mol, 10 eq) was added and the reaction mixture was stirred at room temperature overnight.

[0301] The precipitation of copolymer C10 was carried out by pouring the reaction mixture into 50 mL of MTBE while stirring vigorously at room temperature. After filtration, the product was slurried again with 2 × 10 mL of MTBE and then dried under vacuum. Copolymer C10 was obtained in a yield of 83%.

[0302] Copolymer C11 was prepared following the same procedure as C10 using C7 as the starting material. Copolymer C11 was obtained in a yield of 87%.

[0303] Copolymer C12 was prepared following the same procedure as C10 using C9 as the starting material. Copolymer C12 was obtained in a yield of 81%.

[0304] The properties of copolymers C10 - C12 are shown in Table 5.

[0305]

Table 5

[0306] Example 4: Preparation of paclitaxel-loaded nanoparticles Paclitaxel (PTX)-loaded nanoparticles were formed by a solvent displacement method, also known as nanoprecipitation.

[0307] Solutions 1 of copolymers C1 - C12 in DMF with a concentration of 200 g / L were prepared. Solution 2 of PTX in DMF with a concentration of 20 g / L was prepared. Using Solutions 1 and 2, Solution 3 with a feed weight ratio (FWR) of 10% containing [C] = 100 g / L and [PTX] = 10 g / L in DMF was prepared.

[0308] Using a syringe pump (Fusion 100-X, Chemyx), 1 mL of Solution 3 was injected into 9 mL of water at a flow rate of 30 mL / min while stirring at 400 rpm. After the addition was complete, stirring was continued for 5 minutes.

[0309] The newly obtained suspension was purified to remove DMF and unfilled drugs by initial filtration through a 0.20 μm PES syringe filter, subsequently by a gel filtration column (PD-10 desalting, Cytiva) using water as the eluent, and finally by filtration through a 0.20 μm PES syringe filter. The resulting nanoparticles of NP1 - NP12 have the characteristics detailed in Table 6.

[0310]

Table 6

[0311] The solubility of PTX in water is lower than 0.1 μg / mL. The results in Table 6 show that the nanoparticles according to the present invention can significantly increase the water solubility of PTX.

[0312] Advantageously, the nanoparticles according to the present invention show only trace amounts of DMF, which is compatible with the use of nanoparticles in pharmaceutical applications.

Claims

1. A linear copolymer comprising a polysarcosine block, pSar, containing 15 to 99 sarcosine structural units, and a poly(amino acid) block, pAA, containing 8 to 120 amino acid structural units.

2. The linear copolymer according to claim 1, having a hydrophilic fraction f(pSar) in the range of 5 to 80%, wherein f(pSar) is the percentage ratio of the number-average molar mass of the pSar blocks based on the number-average molar mass of the linear copolymer.

3. The linear copolymer according to claim 1, wherein the pAA block has a hydrophobic coefficient of -0.50 or higher.

4. The linear copolymer according to claim 1, wherein the amino acid constituent units of the pAA block are hydrophobic amino acids.

5. Equation I or Equation II: 【Chemistry 1】 (In the formula, x is the number of sarcosine units, and is an integer in the range of 15 to 99. y + z is the number of amino acid units, and is an integer in the range of 8 to 120. R ｙ base and R ｚ The group is independently selected from the amino acid side chain groups. R １ａ base and R １ｂ The group is independently selected from H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, and heteroaryl. R ２ The group is selected from H and nitrogen protecting groups. The linear copolymer according to claim 1.

6. The linear copolymer according to claim 5, wherein x is an integer in the range of 20 to 95.

7. The linear copolymer according to claim 5, wherein y + z is an integer in the range of 8 to 110.

8. The linear copolymer according to claim 5, wherein y + z is an integer in the range of 8 to 50.

9. The linear copolymer according to claim 5, wherein y + z is an integer in the range of 55 to 110.

10. R ｙ and R ｚ The linear copolymer according to claim 6, wherein the side chains are independently selected from L-leucine, L-phenylalanine, L-tyrosine, L-gamma-benzyl glutamate, L-gamma-tert-butyl glutamate, L-cyclohexylglycine, D-leucine, D-phenylalanine, D-cyclohexylglycine, D-tyrosine, D-gamma-benzyl glutamate, and D-gamma-tert-butyl glutamate.

11. A method for preparing the linear copolymer described in claim 1 by polymerization of a sarcosine derivative and an amino acid derivative, wherein the derivative is the following formula III and formula IV 【Chemistry 2】 (In the formula, A is either O or S, R ｙ 、R ｚ is as defined in claim 5) A method for preparing a linear copolymer, as represented by [the formula / method].

12. Nanoparticles comprising a linear copolymer according to claim 1, or a linear copolymer prepared according to the method described in claim 11.

13. The nanoparticle according to claim 12, further comprising at least one active compound.

14. The nanoparticles according to claim 13, wherein at least one active compound is selected from hydrophobic active pharmaceutical components.

15. The following conditions: - Hydrodynamic diameter in the range smaller than 400 nm; - A multivariance index in the range lower than 0.70; - A packing efficiency of the active compound that is higher than 20% The nanoparticle according to claim 12, satisfying at least one of the following conditions.

16. The following steps: - Prepare an organic solution containing the linear copolymer described in claim 1. Step, - Next, the organic solution is mixed with the aqueous solution while stirring. - Next, the step of removing the organic solvent. A method for preparing nanoparticles according to claim 12, comprising:

17. The nanoparticles further contain an active compound, and the method is as follows: - Linear copolymer and at least one activation according to claim 1 A step of preparing an organic solution containing a compound, - Next, the organic solution is mixed with the aqueous solution while stirring. - Next, the step of removing the organic solvent. A method for preparing nanoparticles according to claim 16, comprising:

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