Method for preparing ether linkage-bonded porphyrin dimer ester, method for preparing sinoporphyrin sodium, pharmaceutical composition comprising same, and use thereof

Abstract

The present invention relates to a method for preparing an ether linkage-bonded porphyrin dimer ester. The method comprises: reacting protoporphyrin dimethyl ester, which is a compound of formula (III), at -10°C to 10°C in the presence of a halogenated alkane solvent, a hydrogen bromide gas and oxygen to obtain bis[1-[6,7-bis(methyl propionate)-1,3,5,8-tetramethyl-2-vinyl-4-porphin]ethyl]ether, which is a compound of formula (II). In addition, the present invention further relates to a method for preparing sinoporphyrin sodium. The preparation methods have mild reaction conditions, are simple and easy to operate, involve controllable quality, and are suitable for industrial production, and products prepared by the methods have a high purity, a good yield, a longer shelf life, and a good storage stability.

Description

Preparation method of ether-bonded porphyrin dimer ester and sodium porphyrin, pharmaceutical composition containing the same and use thereof Technical Field

[0001] The present invention belongs to the field of pharmaceutical chemistry, and specifically relates to a method for preparing an ether-bonded porphyrin dimer ester, a method for preparing sodium porphyrin, as well as the ether-bonded porphyrin dimer ester and sodium porphyrin prepared by the method, a pharmaceutical composition containing the same, and use of the same as a photosensitizer in photodynamic therapy. Background Art

[0002] Photodynamic therapy (PDT) is a novel therapy that uses photosensitizers, light, and oxygen molecules to produce photodynamic reactions, and then selectively targets diseases such as malignant tumors, vascular lesions, and microbial infections. Photosensitizers are the core of PDT. Currently, the main photosensitizers used in clinical practice include Photofrin from the United States, Photogem from Russia, Photosan from Germany, and Haematodrex from Belgium. However, these photosensitizers still have many disadvantages. For example, they are mostly mixed preparations composed of porphyrin derivatives, the active ingredients are unclear, and there are no controllable quality standards. In addition, they can easily cause skin phototoxic effects such as rashes and blisters due to their long retention time in the skin for several weeks. Patients need to avoid direct sunlight for 1 month or even longer after taking the drug (Fang Qicheng. Cancer photodynamic therapy and the new anticancer photosensitizer sodium porphyrin [J], Chinese Journal of New Drugs, 2014, 23(13): 1540-1545).

[0003] Sinoporphyrin sodium (DVDMS) is a new generation photosensitizer independently developed by my country. It is favored by people because of its clear active ingredient, good water solubility, high content, low effective dose, short light avoidance time after treatment, good safety, and unique fluorescent properties. Since Sinoporphyrin sodium has broad application prospects in anti-tumor, antibacterial, psoriasis treatment, and development of therapeutic diagnostic reagents, it is particularly important to mass-produce Sinoporphyrin sodium with high purity and good yield to meet the growing market demand and increasingly stringent application requirements. However, the method for preparing Sinoporphyrin sodium in the prior art has the disadvantages of low yield, complex process, and low product purity. Therefore, there is still a need for an improved method for mass-producing Sinoporphyrin sodium with high purity and good yield.

[0004] Summary of the Invention

[0005] To solve the above problems, the present invention aims to provide a method for preparing di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether on a large scale with good yield and high purity, a method for preparing sodium porphyrin, as well as ether-bonded porphyrin dimer ester and sodium porphyrin prepared by the method, a pharmaceutical composition containing the same, and use of the same as a photosensitizer for photodynamic therapy.

[0006] In a first aspect of the present invention, there is provided a method for preparing a compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether (hereinafter also referred to as "ether-bonded porphyrin dimer ester"), the method comprising:

[0007] The compound of formula (III), dimethyl protoporphyrin, is reacted at -10-10° C. in the presence of a halogenated alkane solvent, hydrogen bromide gas, and oxygen to obtain the compound of formula (II), di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether.

[0008] Unexpectedly, the inventors discovered that the method of the present invention for preparing the ether-bonded porphyrin dimer ester of the compound of formula (II) directly uses protoporphyrin dimethyl ester as a raw material and adopts a simple "one-step method", which greatly simplifies the process (such as the formation of protoporphyrin dimethyl ester derivatives, the separation of various protoporphyrin dimethyl ester derivatives, etc.), reduces production costs, reduces product losses caused by cumbersome intermediate processing processes, and can be directly used for the synthesis of sodium chloroporphyrin in the form of a solid or solution with a quality suitable for the preparation of sodium chloroporphyrin (for example, with good yield and high purity), thereby being more suitable for industrial production.

[0009] In a second aspect of the present invention, there is provided a method for preparing sodium porphyrin (i.e., bis[1-[sodium 6,7-dipropionate-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether) of the compound of formula (I), the method comprising the following steps:

[0010] (S1) reacting hemin, a compound of formula (IV), with methanol and reduced iron powder in the presence of a halogenated alkane solvent and hydrogen chloride gas to obtain protoporphyrin dimethyl ester, a compound of formula (III);

[0011] (S2) obtaining a compound of formula (II) of formula (II) by the method described in the first aspect of the present invention, di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether from a compound of formula (III);

[0012] (S3) reacting the compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphyrin]ethyl]ether with a sodium hydroxide C1-C3 fatty alcohol solution in the presence of a halogenated alkane solvent to obtain sodium porphyrin of formula (I).

[0013] In the method for preparing sodium chloroporphyrin, a compound of formula (I) according to the present invention, the method may further comprise a step (S4) of purification by preparative high performance liquid chromatography (HPLC).

[0014] In the method for preparing the compound of formula (I) and the compound of formula (II) described in the present invention, the halogenated alkane solvent is selected from C1-C3 halogenated alkanes, preferably at least one selected from dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and dibromomethane, more preferably dichloromethane.

[0015] The advantages of the above-mentioned method for preparing the compound sodium chloroporphyrin of formula (I) are that the reaction raw materials are cheap and readily available, the method for synthesizing the necessary intermediates is simple and easy to operate, the equipment requirements at each stage are low, the reaction conditions are mild, and the quality is controllable, which is conducive to reducing production costs and industrial production of sodium chloroporphyrin. In addition, the sodium chloroporphyrin prepared by the method has better quality, such as high purity, good yield, longer shelf life and good storage stability, for example, a shelf life of more than 24 months, and its purity does not significantly decrease with the extension of storage time.

[0016] The third aspect of the present invention provides a compound of formula (III) prepared by the method described in the second aspect of the present invention, dimethyl protoporphyrin, a compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether, and a compound of formula (I) sodium porphyrin.

[0017] The fourth aspect of the present invention provides a pharmaceutical composition for photodynamic therapy, comprising sodium chloroporphyrin prepared by the method according to the second aspect of the present invention and one or more pharmaceutically acceptable excipients.

[0018] The fifth aspect of the present invention provides use of sodium chloroporphyrin prepared by the method according to the second aspect of the present invention in preparing a drug used as a photosensitizer for photodynamic therapy. DETAILED DESCRIPTION

[0019] The preferred embodiments of the present invention will be described in detail below. It should be noted that the present application is not limited to these embodiments. These embodiments are merely exemplary, and those skilled in the art may make various modifications, additions, and substitutions to the present invention without departing from the scope and spirit of the present invention.

[0020] " range " disclosed in the present application is limited in the form of lower limit and upper limit, and given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of special range. The scope limited in this way can be to include end value or not include end value, and can be arbitrarily combined, that is, any lower limit can form a range with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for specific parameters, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range value 1 and 2 are listed, and if the maximum range value 3,4 and 5 are listed, then the following range can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In this application, unless otherwise specified, the numerical range " ab " represents the abbreviation of any real number combination between a and b, wherein a and b are all real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0021] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions.

[0022] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form new technical solutions.

[0023] Unless otherwise specified, all steps of the present invention may be performed sequentially or randomly, preferably sequentially. For example, the method comprising steps (a) and (b) indicates that the method may comprise steps (a) and (b) performed sequentially, or may comprise steps (b) and (a) performed sequentially. For example, the method further comprising step (c) indicates that step (c) may be added to the method in any order, for example, the method may comprise steps (a), (b) and (c), or may comprise steps (a), (c) and (b), or may comprise steps (c), (a) and (b), etc.

[0024] Unless otherwise specified, the terms "include" and "comprising" used in this application may be open-ended or closed-ended. For example, "include" and "comprising" may mean that other members, elements, or method steps not listed may also be included or comprised, or may mean that only the other members, elements, or method steps listed may be included or comprised.

[0025] The terms "above" and "below" used in this application include the number, for example, "one or more" means one or more, and "one or more of A and B" means "A", "B" or "A and B".

[0026] Unless otherwise specified, the term "or" is inclusive in this application. For example, the phrase "A or B" means "A, B, or both A and B." More specifically, the condition "A or B" is satisfied if any of the following conditions are met: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0027] In the present invention, unless otherwise stated, all operations are carried out at normal temperature and pressure.

[0028] As used herein, "C1-C3 fatty alcohol" refers to a linear or branched saturated aliphatic alcohol containing 1 to 3 carbon atoms, preferably a linear or branched saturated aliphatic monohydric alcohol containing 1 to 3 carbon atoms, examples of which include but are not limited to methanol, ethanol, propanol or isopropanol.

[0029] As used herein, "C1-C3 haloalkane" refers to a straight-chain saturated C1-C3 alkyl group which is mono- or poly-substituted, preferably poly-substituted, by a halogen (e.g., chlorine, bromine) atom, examples of which include but are not limited to dichloromethane, dibromomethane, trichloromethane, tetrachloromethane or dichloroethane.

[0030] Unless otherwise specified, in this application, the expression "compound of formula (I)" can be used interchangeably with "bis[1-[sodium 6,7-dipropionate-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether" and "sodium porphyrin"; the expression "compound of formula (II)" can be used interchangeably with "bis[1-[methyl 6,7-dipropionate-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether" and "ether-bonded porphyrin dimer ester".

[0031] As used herein, the term "pharmaceutically acceptable excipient" refers to a substance that is useful in preparing a pharmaceutical composition and is generally safe, non-toxic, and not biologically or otherwise undesirable, and includes excipients that are acceptable for veterinary as well as human pharmaceutical use.

[0032] Unless otherwise stated, contents and percentages throughout this application are based on weight.

[0033] In this application, unless otherwise specified, the water used in this article is purified water, which complies with the provisions on purified water in Part II of the "Chinese Pharmacopoeia" (2020 edition). This can minimize the types and contents of impurities contained in the final product.

[0034] In a first aspect of the present invention, there is provided a method for preparing a compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether, the method comprising:

[0035] The compound of formula (III), dimethyl protoporphyrin, is reacted at -10-10° C. in the presence of a halogenated alkane solvent, hydrogen bromide gas, and oxygen to obtain the compound of formula (II), di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether.

[0036] In a preferred embodiment, the halogenated alkane solvent is selected from C1-C3 halogenated alkanes, preferably at least one selected from dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and dibromomethane, more preferably dichloromethane.

[0037] In a preferred embodiment, the reaction is carried out at -10-10°C, preferably -5-5°C, for 15-22 hours, preferably 16-20 hours.

[0038] In a preferred embodiment, the weight ratio of the compound of formula (III) dimethyl protoporphyrin to hydrogen bromide gas is 1:(0.7-1.4), preferably 1:(0.75-1.3), and more preferably 1:(0.8-1.2).

[0039] In a preferred embodiment, the molar content of oxygen in the hydrogen bromide gas in the reaction system is 4% to 6%, preferably 4.5% to 5.5% (based on the total amount of hydrogen bromide gas and oxygen gas). The oxygen can be derived from the oxygen already present in the reaction system, oxygen additionally introduced into the reaction system, etc., preferably oxygen additionally introduced into the reaction system.

[0040] In the method for preparing the compound of formula (II) of the present invention, the reaction is terminated by adding water at 20-30° C. Preferably, the amount of water added is 9-11 times, preferably 9.5-10.5 times, the amount of water added is that of dimethyl protoporphyrin.

[0041] In the method for preparing the compound of formula (II), the amount of the halogenated alkane solvent used is 10-18 times, preferably 12-16 times, and more preferably 13-15 times the total weight of protoporphyrin dimethyl ester and hydrogen bromide gas.

[0042] Preferably, in a specific embodiment, the amount of dichloromethane used is 10-18 times, preferably 12-16 times, more preferably 13-15 times the total weight of protoporphyrin dimethyl ester and hydrogen bromide gas.

[0043] In the above method for preparing the compound of formula (II), the reaction apparatus used for the reaction may be a reaction apparatus conventionally used in the art, such as a reactor equipped with a stirrer and a temperature control unit.

[0044] In the above-mentioned method for preparing the compound of formula (II), the method may further include a post-treatment step of the reaction mixture, and the post-treatment step may be selected from extraction, filtration, concentration under reduced pressure, purification and drying. In a preferred embodiment, the method may further include a step of adjusting the pH of the system mixture before the post-treatment. In a more preferred embodiment, before the post-treatment, the pH of the system is adjusted at 20-30°C using a 7% sodium bicarbonate solution, preferably to a pH of 5-9.

[0045] In the above-mentioned method for preparing the compound of formula (II), if present, the extraction is carried out at 20-30° C. In order to further improve the purity of the target product, the mixture obtained by the reaction can be extracted once or multiple times as needed. In the case of multiple (preferably two) extractions, the extraction methods can be the same or different. In the present invention, there is no particular limitation on the extraction apparatus used, as long as it can achieve the purpose of extraction, such as an extraction tower, a static mixer, a reaction apparatus with stirring, etc., preferably a reactor with a stirrer.

[0046] In a preferred embodiment, the method may further include extracting the mixture obtained by the reaction, wherein the extraction is performed using water and dichloromethane, and the weight ratio of water to dichloromethane is 1:(1-1.5), preferably 1:(1.1-1.3). By extracting and combining the organic phases, the loss of the ether-bonded porphyrin dimer ester of the compound of formula (II) separated from the mixture can be reduced.

[0047] In a preferred embodiment, the method may further comprise the step of filtering the reaction mixture. In a more preferred embodiment, the method may further comprise the step of extracting the reaction mixture and then filtering the extracted organic phase.

[0048] In the above-mentioned method for preparing the compound of formula (II), if present, the mixture obtained by the reaction can be filtered more than once, preferably 1-3 times, more preferably 1 time, as needed. In the case of multiple filtrations, the filtration methods can be the same or different. The filtration methods include positive pressure filtration, vacuum filtration, centrifugal filtration, etc. More preferably, the filtration is carried out by a positive pressure plate filter, preferably a stainless steel filter plate filter. The filter membrane pore size of the filter is 5 μm to 20 μm, preferably 8 to 15 μm.

[0049] In a preferred embodiment, the method may further comprise the step of concentrating the reaction mixture under reduced pressure. In a more preferred embodiment, the method may further comprise the step of filtering the reaction mixture and then concentrating under reduced pressure, wherein the filtered filtrate may be concentrated under reduced pressure at a temperature not higher than 25° C. to a concentration endpoint volume to obtain a concentrated solution containing the compound protoporphyrin dimethyl ester of formula (III).

[0050] Unless otherwise specified, the term "concentration endpoint volume" means the concentration of the liquid to be concentrated to a volume 2-4 times the total amount (in kg) of the main raw materials charged to the reaction (e.g., excluding solvents used for washing the reaction unit or post-processing), expressed in liters. For example, if 1 kg of the main raw materials charged to the reaction is used, the concentration endpoint volume is 2-4 liters.

[0051] In the present application, there is no particular limitation on the device for vacuum concentration, as long as it can achieve the purpose of vacuum concentration. Preferably, the device for vacuum concentration can be selected from a falling film evaporator, a natural circulation evaporator, a vacuum distillation column, a rotary evaporator, a reactor for concentration, etc., preferably a rotary evaporator or a reactor for concentration, wherein the reactor for concentration is equipped with an agitator, a temperature control unit, a decompression device and a secondary condenser, and the internal pressure of the reactor is -0.09 to 0 MPa.

[0052] In a preferred embodiment, the method further comprises the step of purifying the reaction mixture by chromatography, wherein the purification is performed by preparative medium pressure liquid chromatography (MPLC) using 10% acetone solution and dichloromethane as eluents. Preferably, the reaction mixture is purified by preparative medium pressure liquid chromatography (MPLC) more than once, preferably 1-3 times, more preferably 2 times.

[0053] In a more preferred embodiment, the method may further include concentrating the reaction mixture under reduced pressure, and then purifying the concentrated solution obtained after concentration twice by preparative medium pressure liquid chromatography (MPLC). Preferably, after one purification by preparative medium pressure liquid chromatography (MPLC), a product solution comprising an ether-bound porphyrin dimer ester of a compound of formula (II), a cross-solution comprising an ether-bound porphyrin dimer ester of a compound of formula (II), and a product-free solution comprising porphyrin derivative impurities are obtained. Optionally, the cross-solution comprising an ether-bound porphyrin dimer ester of a compound of formula (II) can be washed with dichloromethane and concentrated under reduced pressure.

[0054] In another preferred embodiment, when the reaction mixture is purified once by preparative medium pressure liquid chromatography, the eluent used is 10% acetone solution and dichloromethane, wherein the volume ratio of 10% acetone solution to dichloromethane is 1:(4-9).

[0055] In a preferred embodiment, a primary purification is performed by preparative medium pressure liquid chromatography (MPLC), and then the product solution of the ether-bonded porphyrin dimer ester of the compound of formula (II) obtained after the primary purification is subjected to a secondary purification, wherein the eluent is 10% acetone solution and dichloromethane, and the ratio (volume ratio) of the 10% acetone solution and dichloromethane is 1: (6-14), preferably 1: (7-12), and more preferably 1: (8-10).

[0056] In the above-mentioned method for preparing the compound of formula (II), the ether-bonded porphyrin dimer ester of the compound of formula (II) is separated from the mixture obtained by the reaction by preparative medium pressure liquid chromatography (MPLC) using a 10% acetone solution and dichloromethane eluent in a specific volume ratio set in series. At the same time, some impurities in the target product are removed, thereby increasing the relative purity of the target product in the mixture from about 15% to more than 90%, thereby greatly improving the yield.

[0057] In the method for preparing the compound of formula (II) of the present invention, the method may further comprise washing and concentration under reduced pressure steps after chromatographic separation.

[0058] In a specific embodiment, the product solution containing the ether-bonded porphyrin dimer ester of the compound of formula (II) obtained after purification by preparative medium pressure liquid chromatography (MPLC) is washed with dichloromethane at a temperature not higher than 25° C. and concentrated under reduced pressure to 1 / 10 of the original volume to obtain a dichloromethane solution of the ether-bonded porphyrin dimer ester of the compound of formula (II).

[0059] In the above method for preparing the compound of formula (II), the method may optionally further comprise a drying step, such as freeze drying, infrared drying, vacuum drying, etc. The drying apparatus may be selected from a tray oven, a vacuum drying oven and a freeze dryer, preferably a vacuum drying oven.

[0060] Preferably, the dichloromethane solution of the ether-bonded porphyrin dimer ester of the compound of formula (II) obtained after secondary purification by preparative medium-pressure liquid chromatography and reduced-pressure concentration can be directly used in the next step of synthesizing sodium chloroporphyrin without drying, which simplifies the intermediate processing operations, such as dissolution, filtration, etc., and is very beneficial to the industrial production of sodium chloroporphyrin.

[0061] Optionally, the method further comprises a recovery step. In a specific embodiment, the gas stream evaporated during the vacuum concentration process is condensed for recovery using a condenser, preferably a condenser comprising a front-stage condenser and a rear-stage condenser, or is recovered by a vacuum distillation column.

[0062] In a second aspect of the present invention, there is provided a method for preparing sodium porphyrin (i.e., bis[1-[sodium 6,7-dipropionate-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether) of the compound of formula (I), the method comprising the following steps:

[0063] (S1) reacting hemin, a compound of formula (IV), with methanol and reduced iron powder in the presence of a halogenated alkane solvent and hydrogen chloride gas to obtain protoporphyrin dimethyl ester, a compound of formula (III);

[0064] (S2) obtaining a compound of formula (II) of formula (II) by the method described in the first aspect of the present invention, di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether from a compound of formula (III);

[0065] (S3) reacting the compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphyrin]ethyl]ether with a sodium hydroxide C1-C3 fatty alcohol solution in the presence of a halogenated alkane solvent to obtain sodium porphyrin of formula (I).

[0066] In the method for preparing sodium chloroporphyrin of the compound of formula (I) described in the present invention, the halogenated alkane solvent is selected from C1-C3 halogenated alkanes, preferably at least one selected from dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and dibromomethane, more preferably dichloromethane.

[0067] In the method for preparing sodium chloroporphyrin, a compound of formula (I) according to the present invention, the method may further comprise a step (S4) of purification by preparative high performance liquid chromatography (HPLC).

[0068] Unexpectedly, the inventors found that the method for preparing sodium chloroporphyrin of the present invention has many beneficial effects, such as the reaction raw materials are cheap and readily available, the method for synthesizing the necessary intermediates with a quality suitable for synthesizing sodium chloroporphyrin is simple and easy to operate, the equipment requirements at each stage are low, the reaction conditions are mild, which is conducive to reducing production costs, and is very suitable for the industrial production of sodium chloroporphyrin. In addition, the sodium chloroporphyrin prepared by the method has better quality, such as high purity, good yield, longer shelf life and good storage stability, for example, a shelf life of more than 24 months, and its purity does not decrease significantly with the extension of storage time.

[0069] Each synthesis stage will be described in further detail below.

[0070] [Step (S1)]

[0071] In the above-mentioned method for preparing sodium protoporphyrin of the compound of formula (I), in step (S1), hemin of the compound of formula (IV) is reacted with methanol and reduced iron powder in the presence of a halogenated alkane solvent and hydrogen chloride gas to obtain dimethyl protoporphyrin of the compound of formula (III).

[0072] In a preferred embodiment, in step (S1), the reaction is carried out at 18-30°C, preferably 20-30°C, for 1-7 hours, preferably 2-6.5 hours, more preferably 3-6 hours.

[0073] In a preferred embodiment, in step (S1), the halogenated alkane solvent is selected from C1-C3 halogenated alkanes, preferably at least one selected from dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and dibromomethane, more preferably dichloromethane.

[0074] In a preferred embodiment, in step (S1), the weight ratio of the compound of formula (IV) hemin, reduced iron powder, hydrogen chloride gas and methanol is 1: (0.045-0.065): (1.08-1.35): (7.7-8.0), preferably 1: (0.048-0.06): (1.1-1.32): (7.8-8.0), more preferably 1: (0.05-0.06): (1.1-1.3): (7.8-7.9).

[0075] In some embodiments, in step (S1), the reaction is carried out at a reaction pressure of no higher than 0.06-0.09 MPa, preferably no higher than 0.03-0.05 MPa, and more preferably 0.01 MPa. In the method for preparing the compound of formula (I) of the present invention, excessive pressure may break the rupture disc of the reaction apparatus, possibly causing leakage of reactants, thereby adversely affecting the environment, while excessive temperature may lead to increased impurities, reduced yield, and affected economic benefits.

[0076] In some embodiments of the present invention, when the reaction in step (S1) is completed, the ratio of the peak areas of hemin to protoporphyrin dimethyl ester measured by high performance liquid chromatography (HPLC) is ≤3%, preferably ≤2%, more preferably ≤1%.

[0077] In a preferred embodiment, in step (S1), the reduced iron powder is added in batches, preferably in three batches.

[0078] In a preferred embodiment, in step (S1), the amount of the solvent used in the reaction is 1-2 times, preferably 1-1.8 times, the total weight of hemin, reduced iron powder, hydrogen chloride gas and methanol.

[0079] In the present application, in step (S1), the reaction is carried out under an inert gas atmosphere. Preferably, the inert gas can be selected from at least one of nitrogen and argon, preferably nitrogen.

[0080] In the method for preparing the compound of formula (I) of the present invention, the reaction apparatus used for the reaction is as defined above in the first aspect of the present invention.

[0081] In the method for preparing the compound of formula (I) of the present invention, in step (S1), a post-treatment step of the reaction mixture may be further included, and the post-treatment step may be selected from extraction, filtration, washing, reduced pressure concentration and drying. In a preferred embodiment, in step (S1), the pH of the system mixture may be adjusted before the post-treatment. In a more preferred embodiment, triethylamine is used to adjust the pH of the system at 10-20°C.

[0082] In a preferred embodiment, step (S1) may further include extracting the reaction mixture using water to obtain an organic phase containing protoporphyrin dimethyl ester and an aqueous phase containing an iron salt, and separating the organic phase. Preferably, the organic phase separated after extraction may be subjected to a second extraction in the same manner.

[0083] Unless expressly stated otherwise, general descriptions regarding the extraction involved in step (S1) are as defined above in relation to the first aspect of the present invention.

[0084] In a preferred embodiment, when the reaction mixture is subjected to secondary extraction, the pH of the system is adjusted to 1-3 using triethylamine before the first extraction, and the pH of the system is adjusted to 7-8 using triethylamine before the secondary extraction.

[0085] In a preferred embodiment, in step (S1), the step of concentrating the reaction mixture under reduced pressure may also be included. In a more preferred embodiment, in step (S1), the step of filtering the reaction mixture and then concentrating under reduced pressure may also be included. Unless otherwise expressly stated, the general description of the filtration step involved in step (S1) is as defined above in the first aspect of the present invention.

[0086] In a preferred embodiment, step (S1) may further include a washing step after the reaction mixture is concentrated under reduced pressure, wherein the mixture is washed with dichloromethane and methanol, and then dried at a temperature below 35° C., preferably 20-30° C. Preferably, the drying device used can be selected from a tray oven, a vacuum drying oven, and a freeze dryer, preferably a vacuum drying oven.

[0087] [Step (S2)]

[0088] In the above-mentioned method for preparing sodium protoporphyrin of the compound of formula (I), in step (S2), the compound of formula (III), dimethyl protoporphyrin, is reacted at -10-10°C in the presence of a halogenated alkane solvent, hydrogen bromide gas, and oxygen to obtain an ether-bonded porphyrin dimer ester of the compound of formula (II).

[0089] The various features, parameters, conditions, other elements and combinations thereof involved in step (S2) are as defined in the method for preparing the compound of formula (II) in the first aspect of the present invention.

[0090] [Step (S3)]

[0091] In the above-mentioned method for preparing sodium porphyrin of the compound of formula (I), in step (S3), the ether-bonded porphyrin dimer ester of the compound of formula (II) (i.e., di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether) is mixed and reacted with a sodium hydroxide C1-C3 fatty alcohol solution in the presence of a halogenated alkane solvent to obtain sodium porphyrin of the compound of formula (I).

[0092] In a preferred embodiment, in step (S3), the reaction is carried out at 15-30°C, preferably 15-25°C, for 6-18 hours, preferably 8-16 hours.

[0093] In a preferred embodiment, in step (S3), the C1-C3 fatty alcohol is selected from methanol, ethanol, propanol or a mixture thereof, preferably methanol.

[0094] In the method for preparing sodium porphyrin of the present invention, in step (S3), the weight ratio of the ether-bonded porphyrin dimer ester of the compound of formula (II) to the sodium hydroxide C1-C3 fatty alcohol solution is 1:(10-15), preferably 1:(11-14), wherein the weight ratio of sodium hydroxide to C1-C3 fatty alcohol is 1:(13-22), preferably 1:(15-20), and more preferably 1:(16-18).

[0095] In a specific embodiment, in step (S3), the weight ratio of the ether-bonded porphyrin dimer ester of the compound of formula (II) to the sodium hydroxide methanol solution is 1:(10-15), preferably 1:(11-14), wherein the weight ratio of sodium hydroxide to methanol is 1:(13-22), preferably 1:(15-20), and more preferably 1:(16-18).

[0096] In the method for preparing sodium porphyrin of the present invention, in step (S3), the amount of the halogenated alkane solvent used for dissolution is 1-30 times, preferably 2-29 times, and more preferably 3-28 times the weight of the ether-bonded porphyrin dimer ester.

[0097] In a specific embodiment, in step (S3), the amount of dichloromethane used for dissolution is 1-30 times, preferably 2-29 times, more preferably 3-28 times the weight of the ether-bonded porphyrin dimer ester.

[0098] In a preferred embodiment, in step (S3), the step of filtering the mixture obtained by the reaction may also be included. The filtration is carried out by means of a filter with reduced pressure suction filtration. The filter is a tower filter having a pore size of 5-20 μm, preferably 8-15 μm. In particular, in the filtration operation, anhydrous ethanol is used to wash the mixture to obtain an ethanol solution of sodium chloroporphyrin, a compound of formula (I). Preferably, the ethanol solution containing sodium chloroporphyrin is dried under reduced pressure in a vacuum drying oven at a temperature not higher than 45°C, preferably at a temperature of 20-40°C. Optionally, the ethanol solution containing sodium chloroporphyrin may also be concentrated under reduced pressure before drying.

[0099] [Step (S4)]

[0100] In a preferred embodiment, the method further comprises a purification step by preparative high performance liquid chromatography (HPLC). In this step, the compound of formula (I) obtained in step (S3), sodium chloroporphyrin, is dissolved in a mixture of methanol and water, the pH of the system is adjusted with 0.5N hydrochloric acid (preferably to a pH of 9-10), the resulting mixture is filtered, washed, and enriched, and the enriched solution is subjected to reduced pressure concentration, washing, and drying steps to obtain refined sodium chloroporphyrin.

[0101] In the method for preparing sodium chloroporphyrin of the present invention, a mixture containing the target product sodium chloroporphyrin is separated and enriched by using methanol and water as eluents in a specific ratio set in preparative high-performance liquid chromatography, thereby obtaining a high-purity product concentrate suitable for subsequent processing steps such as freeze-drying.

[0102] In a preferred embodiment, in step (S4), the weight ratio of methanol to water used to dissolve the compound of formula (I), sodium chloroporphyrin, is 1:(2-6), preferably 1:(3-5).

[0103] In a preferred embodiment, in step (S4), the purification step is performed by preparative high performance liquid chromatography (HPLC) using methanol and water as eluents.

[0104] In a preferred embodiment, step (S4) may further include a filtration step, wherein the filtration is performed through a filter in a positive pressure filtration manner more than once, preferably 1-3 times, more preferably 2 times. Preferably, during the filtration process, methanol and water are used for washing once, wherein the weight ratio of methanol to water is 1:(2.5-4.5), preferably 1:(3-4). In a preferred embodiment, the filter is a pipeline filter, which may be a straight-through type, T-type, Y-type, etc., preferably a straight-through type. The pore size of the pipeline filter is 0.2-0.6 μm, preferably 0.4-0.5 μm.

[0105] In a preferred embodiment, in step (S4), the solution enriched by preparative high performance liquid chromatography (HPLC) is washed with acetonitrile and water.

[0106] In a preferred embodiment, the mixture obtained by dissolving the compound sodium porphyrin of formula (I) in step (S3) is enriched once or more, preferably 1-3 times, more preferably 2 times, by preparative high performance liquid chromatography (HPLC), wherein the eluent is methanol and water. In particular, the elution gradient methanol (A) and water (B) used for enrichment by preparative high performance liquid chromatography (HPLC) are A / B=10:90 and 70:30 by volume, and the flow rate A+B is 200-300mL / min, preferably 220-280mL / min.

[0107] In a preferred embodiment, before the mixture obtained by dissolving the compound of formula (I) in step (S3) is enriched, more than one chromatographic separation can be carried out by preparative high performance liquid chromatography (HPLC), preferably 1-3 times, more preferably 2 times, wherein the eluent is methanol and water. In particular, the volume ratio of the elution gradient methanol (A) and water (B) used in the chromatographic separation carried out before enrichment by preparative high performance liquid chromatography (HPLC) is A / B=45:55, 100:0 and 10:90, wherein the flow rate A+B when A / B=45:55 is 100-180mL / min, preferably 110-150mL / min, and the flow rate A+B when A / B=100:0 and 10:90 is 200-300mL / min, preferably 220-280mL / min.

[0108] In step (S4), separation and enrichment by preparative high performance liquid chromatography (HPLC) were performed using a wet column packing method, using a methanol (A) / water (B) ratio of A / B = 10:90, and equilibrated the column for 10 minutes.

[0109] In the method for preparing sodium chloroporphyrin described herein, step (S4) may further include a vacuum concentration step after purification by preparative high performance liquid chromatography, wherein the vacuum concentration device is not particularly limited, as long as it can achieve the purpose of vacuum concentration. Preferably, the vacuum concentration is performed by a rotary evaporator at ≤15°C, and the internal pressure of the rotary evaporator is -0.09 MPa to 0 MPa.

[0110] In a preferred embodiment, step (S4) may further include a drying step, wherein the drying step is freeze-drying and is performed using a freeze-drying apparatus conventional in the art, preferably a flat-plate freeze dryer. Preferably, the water content (% w / w) of the sodium chloroporphyrin obtained after the drying step is ≤10%.

[0111] In the present application, the determination of water content is a method well known to those skilled in the art, such as the Karl Fischer method for determining water content.

[0112] The third aspect of the present invention provides a compound of formula (III) prepared by the method described in the second aspect of the present invention, dimethyl protoporphyrin, a compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether, and a compound of formula (I) sodium protoporphyrin.

[0113] The fourth aspect of the present invention provides a pharmaceutical composition for photodynamic therapy, comprising sodium chloroporphyrin prepared by the method according to the second aspect of the present invention and one or more pharmaceutically acceptable excipients.

[0114] The compound of formula (I) of the present invention, sodium chloranthate, can be formulated into any suitable galenic formulation and can be administered by any suitable route. For example, sodium chloranthate, a compound of formula (I) of the present invention, can be formulated into solutions, suspensions, emulsions, lyophilized preparations, etc. for injection (e.g., intra-arterial, intravenous, intramuscular, subcutaneous, intraperitoneal injection, etc.) or infusion; formulated into tablets, solutions, capsules, etc. for oral administration; formulated into ointments, creams, suppositories, patches, etc. for topical administration; and formulated into aerosols, sprays, powders, etc. for inhalation administration.

[0115] The methods for formulating the compound of formula (I) of the present invention, sodium chloroporphyrin, into galenical formulations and the pharmaceutically acceptable excipients that can be used are conventional methods and known excipients well known to those skilled in the art. For example, information regarding these galenical formulations and suitable excipients is provided in the following literature: Luo Mingsheng and Gao Tianhui, eds., "Compendium of Pharmaceutical Excipients," 2nd edition, Sichuan Science and Technology Press. Those skilled in the art can adjust the formulation within the scope of the teachings of this specification to provide various formulations for specific routes of administration without destabilizing the compounds of the present invention or impairing their therapeutic activity.

[0116] The fifth aspect of the present invention provides use of sodium chloroporphyrin prepared by the method according to the second aspect of the present invention in preparing a drug used as a photosensitizer for photodynamic therapy.

[0117] It should be noted that in this specification, the various characteristics, parameters, conditions, other elements and their combinations described in relation to the preparation methods and products of sodium chloroporphyrin and the intermediates used to synthesize it are applicable to the pharmaceutical compositions and uses thereof.

[0118] The present invention will be further described in more detail with reference to the following examples. However, these examples are merely illustrative and should not be interpreted as limiting the scope of the present invention in any way.

[0119] Example

[0120] All reagents and instruments used without manufacturer indication are commercially available conventional products commonly used in this field.

[0121] Example 1

[0122] S1. Preparation of compound protoporphyrin dimethyl ester of formula (III)

[0123] Under a nitrogen atmosphere, 362 volumes (590 g, standard state, 0°C, 101.325 kPa) of hydrogen chloride gas (purchased from Zibo Wandali Special Gas Co., Ltd., purity: ≥99.8%) was introduced into a reactor (Jiangsu Purui Technology, 20 L glass reactor; internal pressure 0.01 MPa) containing 4.95 L of methanol at 15°C and stirred at this temperature for 10-30 minutes. Then, 4.98 L of dichloromethane, 500 g of hemin (Wuhan Dahua Weiye Pharmaceutical Chemical Co., Ltd.), and 25.5 g of reduced iron powder were added at 25°C in three 8.5 g increments, and stirred for 3 hours.

[0124] After the temperature in the reactor was lowered to 15°C, 1000 g of triethylamine was added dropwise to adjust the pH of the system to pH 2. At 25°C, the resulting mixture was divided into two batches, 2.5 L of water (prepared purified water) was added to each batch and stirred for 10 minutes. After standing and stratification, the organic and aqueous phases were transferred and combined. 300 g of triethylamine was then added dropwise to the combined organic phase to adjust the pH of the system to pH 8. The resulting mixture after pH adjustment was divided into two batches, 2.5 L of water was added to each batch and stirred for 10 minutes. After standing and stratification, the organic and aqueous phases were transferred and combined.

[0125] The combined organic phase obtained above was filtered through a positive pressure stainless steel filter plate filter (membrane pore size of 10 μm). The filtrate was concentrated under reduced pressure to 1 / 3 times the original volume at 20°C in a reactor equipped with stirring, a temperature control device, a decompression device and a secondary condenser, and then 0.94L of dichloromethane and 4.42L of methanol were added for washing. The mixed solution was centrifuged through a centrifuge (Jiangsu Saideli Pharmaceutical Machinery Manufacturing Co., Ltd., LLGZ800 type), and the solid was dried at 25°C through a vacuum drying oven (Shanghai Haixiang Instrument Factory, DZF-6090) to obtain 440g of purple-brown crystalline powder protoporphyrin dimethyl ester (yield 97% (by weight, the same below), purity 97%, melting point 226°C). The purity of dimethyl protoporphyrin was analyzed by HPLC (chromatographic column: Waters Sunfire C18; column temperature: 30° C.; mobile phase A: 0.05% trifluoroacetic acid in water, mobile phase B: 0.05% trifluoroacetic acid in acetonitrile, A / B=5 / 95 and 95 / 5, flow rate A+B=1.0 mL / min).

[0126] S2. Preparation of ether-bonded porphyrin dimer ester of compound of formula (II)

[0127] Under a nitrogen atmosphere, 130.7 volumes (472 g, standard conditions, 0°C, 101.325 kPa) of hydrogen bromide gas (purchased from Chengdu Taiyu Special Gas Co., Ltd., purity: ≥99%) and 6.8 volumes (9.8 g, standard conditions, 0°C, 101.325 kPa) of oxygen (molar content in hydrogen bromide gas, approximately 5%) were introduced into a reactor (30 L glass reactor, Nantong, Jiangsu Province, Purui Technology) containing 9.54 L of dichloromethane at 0°C and stirred for 10-30 minutes. 440 g of protoporphyrin dimethyl ester prepared in Example S1 was added and reacted at 0°C for 16 hours. 4.4 L of water was added at 25°C and stirred for 2 hours.

[0128] 4400g of 7% sodium bicarbonate solution was added dropwise to the reactor at 25°C to adjust the pH of the system to pH=7. The resulting mixture was divided into two batches, with 1.98L of dichloromethane and 2.2L of water added to each batch. After stirring and standing, the organic phase and the aqueous phase were transferred and combined respectively. 4.3L of dichloromethane was then added to the combined aqueous phase obtained. After stirring and standing, the organic phase and the aqueous phase were transferred respectively, and the transferred organic phase was combined with the organic phase obtained after the first extraction. The combined organic phases after the secondary extraction were filtered through a stainless steel filter plate filter with a pore size of 10μm. The resulting filtrate was then concentrated under reduced pressure at 20°C in a reactor equipped with stirring, a temperature control device, a decompression device (0.01MPa), and a secondary condenser to a concentrated end point volume of 2L. 662mL of dichloromethane was added to obtain an ether-bonded porphyrin dimer ester-dichloromethane solution.

[0129] The above-mentioned ether-bonded porphyrin dimer ester-dichloromethane solution was purified once by preparative medium pressure liquid chromatography (manufacturer: Jiangsu Hanbang; model: DAC450; filler: FUJI (15 μm); mobile phase A: 10% acetone solution; mobile phase B: dichloromethane) using the cleaning equilibrium column parameters and separation parameters shown in Table 1 (elution gradient using (1) and (2) in series), and the obtained product solution containing ether-bonded porphyrin dimer ester was purified twice using the cleaning equilibrium column parameters and separation parameters shown in Table 1 (elution gradient using (3)) to obtain a product solution containing ether-bonded porphyrin dimer ester, a cross solution containing ether-bonded porphyrin dimer ester, and a product-free solution containing porphyrin derivative impurities. The secondary purified product solution containing the ether-bonded porphyrin dimer ester was then concentrated under reduced pressure at 20° C. in a reactor equipped with a stirrer, a temperature control device, a decompression device, and a secondary condenser. After washing with dichloromethane, the solution was again concentrated under reduced pressure to 2 L. The resulting ether-bonded porphyrin dimer ester-dichloromethane concentrate was dried at 30° C. in a vacuum drying oven (Shanghai Haixiang Instrument Factory, DZF-6090) to obtain 239 g of the ether-bonded porphyrin dimer ester in the form of a black-red powder with a yield of 55.2% and a purity of 98%. The purity of the ether-bound porphyrin dimer ester was analyzed by HPLC (chromatographic column: Waters Xbridge C8; column temperature: 30°C; mobile phase A: 0.05% trifluoroacetic acid in water, mobile phase B: 0.05% trifluoroacetic acid in acetonitrile, A / B = 70 / 30, 25 / 75 and 5 / 95, flow rate A+B = 0.8 mL / min).

[0130] Table 1

[0131] S3. Preparation of the compound of formula (I) sodium porphyrin

[0132] S3-a: Under a nitrogen atmosphere, 239 g of the ether-bonded porphyrin dimer ester prepared in Example S2 was dissolved in 4.78 L of dichloromethane and mixed with a methanolic sodium hydroxide solution prepared in advance in a reactor (Nantong Purui Technology, 10 L glass reactor) from 3.63 L of methanol and 167.3 g of sodium hydroxide. The mixture was stirred at 20° C. for 16 hours and allowed to stand. The mixture was then filtered through a tower filter (Tianjin Jinteng Experimental Equipment Co., Ltd., 10 L glass filtration device, filter membrane pore size 10 μm), washed with 303 mL of ethanol, and after concentration, the resulting ethanolic solution containing sodium porphyrin was dried in a vacuum drying oven (Shanghai Haixiang Instrument Factory, DZF-6090) at 35° C. to obtain 228 g of sodium porphyrin with a purity of 96% and a yield of 95%. The purity of sodium chloroporphyrin was analyzed by HPLC (chromatographic column: Waters Xbridge C8; column temperature: 30°C; mobile phase A: 0.05% trifluoroacetic acid in water, mobile phase B: 0.05% trifluoroacetic acid in acetonitrile, A / B = 70 / 30, 25 / 75 and 5 / 95, flow rate A+B = 0.8 mL / min).

[0133] S3-b: Under a nitrogen atmosphere, 2 L of the ether-bonded porphyrin dimer ester-dichloromethane concentrate to be dried, prepared in Example S2, was mixed with a sodium hydroxide methanol solution prepared in advance from 3.63 L of methanol and 167.3 g of sodium hydroxide in a reactor (Nantong Purui Technology, 30 L glass reactor). The mixture was stirred at 20°C for 16 hours and allowed to stand. The mixture was then filtered through a tower filter (Tianjin Jinteng Experimental Equipment Co., Ltd., 10 L glass filtration unit, 10 μm membrane pore size), washed with 320 mL of ethanol, and the resulting ethanol solution containing sodium chloroporphyrin was dried in a vacuum drying oven (Shanghai Haixiang Instrument Factory, DZF-6090) at 35°C to obtain 220 g of sodium chloroporphyrin with a purity of 95% and a yield of 91.5%. The residual dichloromethane (% w / w) was 0.27%, and the residual methanol (% w / w) was 0.15%.

[0134] S4. Refining Steps

[0135] 5.68 L of methanol and 18 L of water were mixed in a reaction kettle. Under a nitrogen atmosphere, 228 g of sodium chloroporphyrin, a compound of formula (I) prepared in Example S3-a, was added with stirring at 25° C. to fully dissolve the compound. 36 g of 0.5 N hydrochloric acid was added dropwise in batches to adjust the pH of the system to 9. The resulting mixture was filtered through a pipeline filter (Millipore, pore size: 0.45 μm). The resulting filtrate was subjected to preparative high pressure liquid chromatography (manufacturer: Jiangsu Hanbang; model: DAC80; column diameter: 8 cm; mobile phase A: 45% methanol; mobile phase B: 55% purified water) using the separation parameters shown in Table 2. Chromatographic separation was performed twice (using elution gradient (1)) to obtain a product solution containing sodium chloroporphyrin with a purity of 98%, a crossover solution containing sodium chloroporphyrin, and a product-free solution containing other impurities.

[0136] The above-mentioned product solution containing sodium chrysophorphyrin was enriched once by preparative high pressure liquid chromatography (manufacturer: Jiangsu Hanbang; model: DAC80; column diameter: 8 cm; mobile phase A: methanol; mobile phase B: purified water) using the parameters for enrichment shown in Table 2 to obtain an enriched product solution containing sodium chrysophorphyrin. The product solution was concentrated under reduced pressure (4 times, first washed with 4L water and 1.7L acetonitrile, then washed with acetonitrile each time) to 2L at 10°C using a rotary evaporator (internal pressure of -0.06MPa) to obtain an acetonitrile-water concentrated solution containing sodium chrysophorphyrin. The acetonitrile-water concentrated solution containing sodium chrysophorphyrin was enriched twice by preparative high pressure liquid chromatography using the same parameters as the first enrichment to obtain a product solution containing sodium chrysophorphyrin. The product solution after secondary enrichment was concentrated in batches at 10° C. under reduced pressure using a rotary evaporator (internal pressure of −0.06 MPa), then washed with 2.7 L of water and 2.7 L of acetonitrile, and concentrated to 2 L under reduced pressure. The acetonitrile-water concentrated solution containing sodium chloroporphyrin was combined.

[0137] Table 2

[0138] The acetonitrile-water concentrated solution containing sodium porphyrin obtained after the secondary enrichment was passed through a flat-plate freeze dryer (Shanghai Dongfulong Technology Co., Ltd., 2m 2 ) was freeze-dried to obtain 194 g of refined sodium porphyrin with a purity of 99.6%, a purification yield of 85%, and a moisture content of 3.3%.

[0139] Calculations show that the total weight yield of the method for preparing sodium chloroporphyrin of formula (I) is 51%. The total weight yield of sodium chloroporphyrin synthesized from dimethyl protoporphyrin of formula (III) is 52.4%.

[0140] 1H NMR (δ, ppm): 10.30, 10.08, 9.99, 9.93 (each s, 1H, meso H); 8.28 (m, 1H, CH=CH2), 6.41, 6.18 (each s, 1H, meso H) d, 1H, CH=CH2); 6.25 (q, 1H, CH(OH)CH3); 4.33 (m, 2H, 2CH2CH2CO2CH3); 3.69 (s, 9H, 2CO2CH3 and 1CH3); 3.55, 3.51, 3.40 (each s,3H,3CH3); 3.21(t,4H,2CH2CH2CO2CH3); 2.03(d,3H,CH(OH)CH3).

[0141] Accutof CS cryospray mass spectrometer (JEOL, Japan); CSI ion source; spray temperature: room temperature; desolvation temperature: 250°C; solvent: methanol; concentration: 40 ng / uL.

[0142] The cold spray MS data of sodium chloroporphyrin obtained in Example 1 are shown below.

[0143] Cold spray MS m / z: 1253.44 [M+Na] + ,1231.96[M+H] + ,1209.47[M+2H-Na] + ,1187.48[M+3H-2Na] + ,1165.50[M+4H-3Na] + ,1143.52[M+5H-4Na] + .

[0144] High-resolution electrospray ionization mass spectrometry (HR-ESI-MS) gave a quasi-molecular ion peak [M+Na] at m / z 1253.44231. + , corresponding to the molecular formula C 68 H 66 N8O9Na4+Na (calculated value 1253.44412).

[0145] The results of the synthesis reaction and MS analysis both showed that the final product was sodium porphyrin, namely, di[1-[sodium 6,7-dipropionate-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether.

[0146] Example 2

[0147] Preparation of lyophilized solution of sodium chloroporphyrin for injection

[0148] Weigh 10g of the sodium porphyrin raw material prepared in Example 1, place it in a light-proof glass container, add water for injection and dissolve it to a concentration of 2.5mg / mL. The solution is pressure-filtered through a stainless steel bacteria filter, wherein it first passes through a pre-filter membrane with a pore size of 0.45μm, and then through a sterilizing membrane with a pore size of 0.2μm. In a sterile operating room, the solution is quantitatively divided into 10mL glass ampoules, and the subpackage volume is 4mL. Freeze dryer is used to vacuum freeze-dry at -20°C to obtain a lyophilized agent for injection.

[0149] Comparative Example 1

[0150] 1. Preparation of ether-bonded porphyrin dimer ester (i.e., bis[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether)

[0151] (a) Preparation of dimethyl protoporphyrin derivative

[0152] Under stirring, 100g of protoporphyrin dimethyl ester was added to 500mL hydrochloric acid to dissolve it completely. The mixture was stirred and reacted in a 25°C water bath for 6 hours. 2800mL of 20% sodium hydroxide solution was added, wherein the solution pH = 13. The reaction was allowed to stand for 1 hour, 500mL of acetic acid was added, and the reaction was continued for another 30 minutes at pH = 5. After suction filtration and washing the filter residue with water, the mixture was drained and placed in a vacuum drying oven to dry to obtain 95g of a brown solid. The above-mentioned 95g solid was dissolved in 1000mL of 5% sulfuric acid methanol solution and stirred and reacted at room temperature for 30 minutes. Then, (NH4)2CO3 was added to neutralize the mixture to pH 7. The mixture was concentrated under reduced pressure. The concentrated solution was extracted with dichloromethane and washed with water. After dehydration with anhydrous sodium sulfate, the mixture was filtered and the dichloromethane was recovered under reduced pressure to obtain the protoporphyrin derivative dimethyl ester. The dimethyl protoporphyrin derivative was dissolved in an appropriate amount of acetone and chromatographed on a silica gel column (1600 g silica gel, 200-400 mesh, pre-balanced with 0.2% methanol-dichloromethane solution) using 0.2% methanol-dichloromethane solution to obtain 78 g of the dimethyl protoporphyrin derivative 4(2)-(1-hydroxyethyl)-6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2(4)-vinylporphyrin, with a yield of 75.7%.

[0153] (b) Separation and purification of dimethyl ester of protoporphyrin derivative

[0154] 78 g of the above-prepared dimethyl protoporphyrin derivative 4(2)-(1-hydroxyethyl)-6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2(4)-vinylporphyrin was dissolved in 400 mL of dichloromethane and chromatographed on a glass chromatography column (1000 g of silica gel, fineness 160-200 mesh, eluent dichloromethane, column diameter 60 mm) to obtain 50 g of 4-(1-hydroxyethyl)-6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2-vinylporphyrin with a purity of 98% and a yield of 64.1%.

[0155] (c) Preparation of ether-bonded porphyrin dimer methyl ester

[0156] 50g of 4-(1-hydroxyethyl)-6,7-bis[2-(methoxycarbonyl)ethyl]-1,3,5,8-tetramethyl-2-vinylporphyrin was dissolved in 3L of anhydrous dichloromethane. 1L of a dichloromethane solution saturated with hydrogen bromide gas was added, and the mixture was shaken thoroughly. The reaction was allowed to proceed in a dark, sealed container. Water was added to terminate the reaction, and the dichloromethane solution was separated, washed with water, and dehydrated with anhydrous sodium sulfate. The dichloromethane was recovered under reduced pressure and purified by silica gel column chromatography (eluting with acetone and dichloromethane (1:60)) to yield 30g of ether-bonded porphyrin dimer methyl ester. The purity was 94%, and the yield was 62.1%.

[0157] 2. Preparation of sodium porphyrin

[0158] 30 g of ether-bonded porphyrin dimer ester was dissolved in 3.6 L of tetrahydrofuran. 2.4 L of 0.1 mol / L aqueous sodium hydroxide solution was added. The mixture was heated under reflux in an oil bath at 80°C in the dark for 8 hours. The aqueous tetrahydrofuran solution was then evaporated under reduced pressure. The dried reaction product was placed in a reflux eluent and refluxed with an appropriate amount of anhydrous ethanol to remove excess sodium hydroxide and other impurities. 18 g of purified sodium porphyrin was obtained with a purity of 98% and a yield of 62.2%.

[0159] The total weight yield of the method in Comparative Example 1 was 18.8%.

[0160] Unexpectedly, compared with the sodium chrysophorphyrin prepared by the prior art method of Comparative Example 1, the sodium chrysophorphyrin prepared by the method of the present invention has a significantly improved yield. For example, the total weight yield of the method for preparing sodium chrysophorphyrin using protoporphyrin dimethyl ester as the starting material is 52.4% (significantly higher than the 18.8% of Comparative Example 1). At the same time, the purity of the obtained sodium chrysophorphyrin is as high as 99.6%. Such high purity is conducive to its application in fields with high application requirements such as anti-tumor, antibacterial, and for the development of therapeutic diagnostic reagents. In addition, the method for preparing sodium chrysophorphyrin of the present invention uses inexpensive and readily available raw materials, has low equipment requirements, and has mild reaction conditions. Various intermediates can be obtained with high quality (e.g., good yield and purity) suitable for the synthesis of sodium chrysophorphyrin, thereby being particularly suitable for the industrial production of sodium chrysophorphyrin.

Claims

1. A method for preparing a compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether, the method comprising: The compound of formula (III), dimethyl protoporphyrin, is reacted at -10-10° C. in the presence of a halogenated alkane solvent, hydrogen bromide gas, and oxygen to obtain the compound of formula (II), di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether.

2. The method according to claim 1, wherein The halogenated alkane solvent is selected from C1-C3 halogenated alkanes, preferably at least one selected from dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and dibromomethane, more preferably dichloromethane.

3. The method according to claim 1 or 2, wherein: The weight ratio of the compound of formula (III) protoporphyrin dimethyl ester to hydrogen bromide gas is 1:(0.7-1.4), preferably 1:(0.75-1.3), and more preferably 1:(0.8-1.2); preferably, in the reaction system, the molar content of oxygen in the hydrogen bromide gas is 4%-6%, preferably 4.5%-5.5%.

4. A method for preparing the compound of formula (I) sodium porphyrin, the method comprising the following steps: (S1) reacting hemin, a compound of formula (IV), with methanol and reduced iron powder in the presence of a halogenated alkane solvent and hydrogen chloride gas to obtain protoporphyrin dimethyl ester, a compound of formula (III); (S2) obtaining a compound of formula (II) of di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphine]ethyl]ether from a compound of formula (III) by the method of any one of claims 1 to 3; (S3) reacting the compound of formula (II) di[1-[6,7-dipropionic acid methyl ester-1,3,5,8-tetramethyl-2-vinyl-4-porphyrin]ethyl]ether with a sodium hydroxide C1-C3 fatty alcohol solution in the presence of a halogenated alkane solvent to obtain sodium porphyrin of formula (I).

5. The method according to claim 4, wherein The halogenated alkane solvent is selected from C1-C3 halogenated alkanes, preferably at least one selected from dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and dibromomethane, more preferably dichloromethane; the C1-C3 fatty alcohol is selected from methanol, ethanol, propanol or a mixture thereof, preferably methanol.

6. The method according to claim 4 or 5, wherein: The method further comprises a step (S4) of purification by preparative high performance liquid chromatography.

7. The method according to claim 4 or 5, wherein: In step (S1), the reaction is carried out at 18-30°C, preferably 20-30°C, for 1-7 hours, preferably 2-6.5 hours, and more preferably 3-6 hours; preferably, the weight ratio of the compound of formula (IV) hemin, reduced iron powder, hydrogen chloride gas and methanol is 1: (0.045-0.065): (1.08-1.35): (7.7-8.0), preferably 1: (0.048-0.06): (1.1-1.32): (7.8-8.0), more preferably 1: (0.05-0.06): (1.1-1.3): (7.8-7.9); preferably, the reduced iron powder is added in batches.

8. The method according to claim 4 or 5, wherein: In step (S3), the reaction is carried out at 15-30°C, preferably 15-25°C, for 6-18 hours, preferably 8-16 hours; preferably, the weight ratio of the compound of formula (II) to the sodium hydroxide C1-C3 fatty alcohol solution is 1:(10-15), preferably 1:(11-14), wherein the weight ratio of sodium hydroxide to C1-C3 fatty alcohol is 1:(13-22), preferably 1:(15-20).

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