Salt form of coronavirus 3CL protease inhibitor as well as preparation method and application of salt form

Abstract

The invention discloses a salt form of a coronavirus 3CL protease inhibitor PLC-01 as well as a preparation method and application of the salt form, and belongs to the technical field of medicinal chemistry. Salt types of PLC-01 comprise inorganic acid salt, organic acid salt, sodium salt and a free state. According to the present invention, various organic acids, inorganic acids and solvents are mainly screened so as to obtain the PLC-01 hydrochloride Pattern A, the PLC-01 mesylate Pattern A, the PLC-01 sodium salt Pattern C and the PLC-01 free state Pattern A, wherein the PLC-01 hydrochloride Pattern A, the PLC-01 mesylate Pattern A, the PLC-01 sodium salt Pattern C and the PLC-01 free state Pattern A have characteristics of high purity and good stability; the invention also discloses a pharmaceutical composition of the salt form of the compound shown in the formula I. All salt forms of PLC-01 in the invention have strong inhibition efficacy on 3CL protease, and are expected to become novel active pharmaceutical ingredients for preventing or treating novel coronavirus infection.

Description

Technical Field

[0001] This invention belongs to the field of medicinal chemistry technology, specifically relating to a salt form of a coronavirus 3CL protease inhibitor, its preparation method, and its application. Background Technology

[0002] The coronavirus 3CL protease (3CLpro, also known as the major protease Mpro) is a key enzyme in viral replication, possessing cleavage site specificity similar to that of the microRNA virus 3C protease, and participating in the replication and transcription of progeny viruses. Composed of 306 amino acids, 3CLpro specifically recognizes and cleaves 11 cleavage sites of non-structural proteins NSP4-NSP16, thereby releasing other non-structural proteins that play important roles in viral genome replication, transcription, and post-translational modifications. Inhibiting 3CLpro can effectively block viral RNA replication and transcription, thus preventing viral proliferation; therefore, 3CLpro is an ideal target for coronavirus targeted drug development.

[0003] PLC-01 is a 3-triazolylmethyl-1,3,5-triazine-2,4-dione compound that has been shown to have a strong inhibitory effect on coronavirus 3CLpro, effectively blocking viral replication and transcription. Therefore, PLC-01 shows great promise as a potential anti-coronavirus drug. However, despite its inhibitory effect on coronavirus 3CL protease, existing PLC-01 crystal forms have some limitations in practical applications. They cannot fully exert their pharmacological activity, and bioavailability and efficacy need further improvement. Furthermore, its antibacterial spectrum is relatively narrow, effective only against specific types of coronaviruses, which limits its clinical application. In addition, PLC-01 also faces the problem of drug resistance with viral mutation and evolution.

[0004] The crystal form of a drug is a crucial factor influencing its physicochemical properties, bioavailability, and efficacy. Different crystal forms of drugs exhibit differences in solubility, stability, hygroscopicity, and dissolution rate, thereby affecting the absorption, distribution, metabolism, and excretion processes. Therefore, the research and optimization of drug crystal forms are key steps in improving drug efficacy and formulation quality. To fully realize the pharmacological activity and clinical therapeutic potential of PLC-01, developing new crystal forms of PLC-01 is particularly important. Summary of the Invention

[0005] In view of the limitations of the existing PLC-01 crystal form, such as low solubility, poor stability, insufficient pharmacological activity, and the need to improve bioavailability and efficacy, the purpose of this invention is to provide a salt form of coronavirus 3CL protease inhibitor, its preparation method and application.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] The first aspect of the present invention discloses a salt form of a coronavirus 3CL protease inhibitor, the structural formula of which is shown in Formula I. The salt form crystal is a free Pattern A crystal and an acid or base addition salt crystal, wherein the acid addition salt crystal is selected from either the hydrochloride Pattern A or the methanesulfonate Pattern A; and the base addition salt crystal is the sodium salt Pattern C.

[0008]

[0009] The free-state Pattern A crystal, when subjected to Cu-Kα radiation, exhibits characteristic diffraction peaks in its X-ray powder diffraction pattern, expressed as 2θ values ​​±0.2°, including: 7.81±0.2°, 13.30±0.2°, 17.01±0.2°, 17.90±0.2°, 19.47±0.2°, 20.19±0.2°, 20.60±0.2°, 23.51±0.2°, 24.93±0.2°, 25.45±0.2°, 26.83±0.2°, 28.26±0.2°, and 30.35±0.2°.

[0010] The characteristic diffraction peaks of the X-ray powder diffraction pattern of the Pattern A hydrochloride crystal, expressed as 2θ value ±0.2°, using Cu-Kα radiation, include: 8.01±0.2°, 14.09±0.2°, 15.95±0.2°, 17.02±0.2°, 20.24±0.2°, 21.04±0.2°, 21.40±0.2°, 21.96±0.2°, 23.38±0.2°, 24.76±0.2°, 25.51±0.2°, 25.83±0.2°, 28.37±0.2°, 30.87±0.2°, and 31.46±0.2°.

[0011] The characteristic diffraction peaks of the X-ray powder diffraction pattern of the methanesulfonate Pattern A crystal, expressed as 2θ value ±0.2°, are as follows: 6.75±0.2°, 7.32±0.2°, 14.81±0.2°, 16.59±0.2°, 18.51±0.2°, 19.14±0.2°, 19.42±0.2°, 21.07±0.2°, 22.36±0.2°, 22.95±0.2°, 25.89±0.2°, 27.21±0.2°.

[0012] The characteristic diffraction peaks of the X-ray powder diffraction pattern of the sodium salt Pattern C crystal, expressed as 2θ value ±0.2°, using Cu-Kα radiation, include: 9.21±0.2°, 9.46±0.2°, 11.02±0.2°, 13.17±0.2°, 16.55±0.2°, 17.66±0.2°, 18.42±0.2°, 21.04±0.2°, 22.10±0.2°, 25.70±0.2°, and 26.52±0.2°.

[0013] The free-state Pattern A crystal also has one or more characteristics selected from the group consisting of:

[0014] (1) The differential scanning calorimetry (DSC) spectrum of the free-state Pattern A crystal shows a broad dehydration peak; and / or

[0015] (2) The thermogravimetric analysis spectrum of the free-state Pattern A crystal shows a weight loss of 6.5% when heated to 200℃; and / or

[0016] (3) The free-state Pattern A crystal absorbs moisture and gains 0.5% weight in an environment of 25°C and 40% to 95% humidity; and / or

[0017] (4) The FT-IR spectrum of the free-state Pattern A crystal has the following characteristic absorption peak, represented by wavelength λ: 3316±2cm -1 3164±2cm -1 3047±2cm -1 2904±2cm -1 2698±2cm -1 1676±2cm -1 1516±2cm -1 1451±2cm -1 1340±2cm -1 1218±2cm -1 1142±2cm -1 1066±2cm -1 959±2cm -1 875±2cm -1 845±2cm -1 779±2cm -1 738±2cm -1 679±2cm -1 634±2cm -1 598±2cm -1 ; and / or

[0018] (5) The free-state PatternA crystal is an irregular particle formed by the aggregation of tiny crystal aggregates with a particle size of 10 to 100 μm.

[0019] The hydrochloride Pattern A crystal also has one or more characteristics selected from the group consisting of:

[0020] (1) The differential scanning calorimetry (DSC) analysis of the Pattern A hydrochloride crystal shows a melting peak after dehydration, and the melting is accompanied by dissociation; and / or

[0021] (2) The thermogravimetric analysis of the hydrochloride Pattern A showed a weight loss of 7.3% when heated to 93°C and a weight loss of 6.5% during the process from 93°C to 180°C; and / or

[0022] (3) The hydrochloride pattern A absorbs moisture and gains approximately 4.3% weight at 25°C and 40% to 80% humidity; and approximately 12.4% weight at 25°C and 80% to 95% humidity; and / or

[0023] (4) The FT-IR spectrum of the hydrochloride pattern A has the following characteristic absorption peak, expressed in wavelength λ: 3132±2cm -1 2932±2cm -1 1729±2cm -1 1581±2cm -1 1506±2cm -1 1463±2cm -1 1428±2cm -1 1395±2cm -1 1331±2cm -1 1285±2cm -1 1246±2cm -1 1189±2cm -1 1151±2cm -1 1088±2cm -1 1027±2cm -1 994±2cm -1 930±2cm -1 886±2cm -1 782±2cm -1 749±2cm -1 691±2cm -1 651±2cm -1 584±2cm -1 ; and / or

[0024] (5) The hydrochloride pattern A is an irregular particle formed by the aggregation of tiny crystal aggregates with a particle size of 2 to 10 μm.

[0025] The methanesulfonate Pattern A crystal also has one or more characteristics selected from the group consisting of:

[0026] (1) The differential scanning calorimetry (DSC) analysis of the methanesulfonate Pattern A crystals showed a melting peak after dehydration; and / or

[0027] (2) The thermogravimetric analysis of the methanesulfonate Pattern A crystal showed a weight loss of 1.9% when heated to 160°C; and / or

[0028] (3) The methanesulfonate Pattern A crystals, when placed in an environment of 25°C and 40% to 80% humidity, showed a moisture absorption weight gain of 3.6%; when placed in an environment of 25°C and 80% to 95% humidity, the moisture absorption weight gain was 84.3%; and / or

[0029] (4) The FT-IR spectrum of the methanesulfonate Pattern A crystal has the following characteristic absorption peak, expressed in wavelength λ: 3109±2cm -1 2960±2cm -1 2796±2cm -1 1753±2cm -1 1663±2cm -1 1559±2cm -1 1464±2cm -1 1385±2cm -1 1347±2cm -1 1291±2cm -1 1202±2cm -1 1138±2cm -1 1087±2cm -1 1040±2cm -1 1005±2cm -1 957±2cm -1 895±2cm -1 850±2cm -1 804±2cm -1 757±2cm -1 705±2cm -1 682±2cm -1 632±2cm -1 ; and / or

[0030] (5) The methanesulfonate Pattern A crystals are irregular particles formed by the aggregation of tiny crystal aggregates with a particle size of 2 to 10 μm.

[0031] The sodium salt Pattern C crystal also has one or more characteristics selected from the group consisting of:

[0032] (1) The differential scanning calorimetry (DSC) spectrum of the sodium salt Pattern C crystal shows a melting peak after dehydration, and the melting is accompanied by dissociation; and / or

[0033] (2) The thermogravimetric analysis (TGA) spectrum of the sodium salt Pattern C crystal showed a weight loss of 3.2% at 90℃ and approximately 4.6% between 90℃ and 220℃; and / or

[0034] (3) The sodium salt Pattern C crystals, when placed at 25°C and with a humidity of 40% to 80%, absorb moisture and gain 32.0% in weight; when placed at 25°C and with a humidity of 80% to 95%, absorb moisture and gain 57.0% in weight; and / or

[0035] (4) The FT-IR spectrum of the sodium salt Pattern C crystal has the following characteristic absorption peak, represented by wavelength λ: 1695±2cm. -1 1568±2cm -1 1482±2cm -1 1408±2cm -1 1364±2cm -1 1307±2cm -1 1269±2cm -1 1200±2cm -1 1090±2cm -1 1005±2cm -1 839±2cm -1 793±2cm -1 745±2cm -1 708±2cm -1 677±2cm -1 652±2cm -1 580±2cm -1 ; and / or

[0036] (5) The sodium salt Pattern C crystal is an irregular particle formed by the aggregation of tiny crystal aggregates with a particle size of 2 to 10 μm.

[0037] The method for preparing the salt form of the coronavirus 3CL protease inhibitor mentioned above includes the following steps:

[0038] (1) Dissolve the coronavirus 3CL protease inhibitor (PLC-01) shown in Formula 1, heat and stir to obtain suspension 1;

[0039] (2) Add solution 2 to the suspension 1 obtained in step (1) and stir to obtain suspension 2; the solution 2 is an acid solution or an alkaline solution, and the acid solution includes organic acid and inorganic acid solutions;

[0040] (3) After the suspension 2 obtained in step (2) is cooled naturally, it is stirred, centrifuged, washed, and vacuum dried to obtain the salt form of coronavirus 3CL protease inhibitor.

[0041] Furthermore, in step (1), the solvent used for dissolution is selected from any one of acetone, methyl tert-butyl ether, ethanol and tetrahydrofuran.

[0042] Further, in step (2), the organic acid is methanesulfonic acid, the inorganic acid is hydrochloric acid, and the alkaline solution is sodium hydroxide solution.

[0043] In step (1), the heating and stirring temperature is 40℃~60℃.

[0044] In step (2), the volume ratio of the suspension to solution 2 is 5 to 8:1.

[0045] In step (3), the temperature is naturally cooled to 24℃~26℃, stirred for 2d~4d, and then vacuum dried at 50℃~60℃ for 18h~24h.

[0046] This invention discloses a salt composition comprising at least two of the following salt compositions: hydrochloride Pattern A, methanesulfonate Pattern A, sodium salt Pattern C, and free Pattern A.

[0047] Based on the total weight of the salt combination, the total mass percentage of hydrochloride Pattern A, methanesulfonate Pattern A, sodium salt Pattern C, and free Pattern A is 60% to 99.999%.

[0048] Furthermore, based on the total weight of the salt combination, the total mass percentage of hydrochloride Pattern A, methanesulfonate Pattern A, sodium salt Pattern C, and free Pattern A is 80% to 99.999%.

[0049] Furthermore, based on the total weight of the salt combination, the total mass percentage of hydrochloride Pattern A, methanesulfonate Pattern A, sodium salt Pattern C, and free Pattern A is 90% to 99.999%.

[0050] The present invention discloses a pharmaceutical composition comprising a salt form of the above-mentioned coronavirus 3CL protease inhibitor, and one or more pharmaceutically acceptable excipients.

[0051] Furthermore, the excipient is selected from fillers, disintegrants, binders, lubricants, or combinations thereof.

[0052] The filler is selected from starch, lactose, microcrystalline cellulose, dextrin, mannitol, magnesium oxide, calcium sulfate, or combinations thereof.

[0053] The disintegrant is selected from carboxymethyl cellulose and its salts, croscarmellose and its salts, croscarmellose, sodium carboxymethyl starch, low-substituted hydroxypropyl cellulose or combinations thereof.

[0054] The adhesive is selected from polyvinylpyrrolidone, hydroxypropyl methylcellulose, starch paste, or combinations thereof.

[0055] The lubricant is selected from magnesium stearate, calcium stearate, or a combination thereof.

[0056] This invention discloses the use of the above-mentioned salt forms of coronavirus 3CL protease inhibitors, or combinations of the above-mentioned salt forms of coronavirus 3CL protease inhibitors, or the above-mentioned pharmaceutical compositions in the preparation of drugs for the prevention or treatment of novel coronavirus infection.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] This invention provides a salt form of a coronavirus 3CL protease inhibitor (PLC-01), including four crystalline forms: hydrochloride Pattern A, mesylate Pattern A, sodium salt Pattern C, and free Pattern A. The formation of different salt forms can alter the chemical structure and surface properties of drug molecules, thereby affecting their solubility in solvents. Salt forms such as hydrochloride and methanesulfonate introduce hydrophilic groups, increasing the interaction between drug molecules and water molecules and improving drug solubility in water, which is crucial for drug absorption and bioavailability. Selecting salt forms with better stability can extend the shelf life of drugs, ensuring quality stability during storage and use, and overcoming the shortcomings of poor stability in existing crystal forms. Different salt forms can alter the charge distribution and spatial conformation of drug molecules, thus affecting the binding ability and affinity of drugs to the coronavirus 3CL protease target, enhancing the inhibitory effect on the target, thereby improving pharmacological activity and fully exerting the antiviral effect of the drug. Compared with existing technologies, the salt form / crystal of this invention not only optimizes the physicochemical properties of the drug but also improves the stability and efficacy of the formulation, laying a solid foundation for the further development, clinical application, and industrialization of the coronavirus 3CL protease inhibitor (PLC-01) as a potential anti-coronavirus drug.

[0059] Furthermore, the free-state Pattern A salt form / crystal exhibits excellent physical stability, effectively resisting the influence of the external environment. No crystal form transformation was observed after DVS (Dynamic Vapor Adsorption) testing, demonstrating its good chemical stability and reducing the risk of drug degradation and transformation during storage and use. The Pattern A salt form / crystal also exhibits good solubility, which helps to improve the drug's dissolution rate. A faster dissolution rate means that the drug can reach an effective concentration in vivo more quickly, thereby enhancing its efficacy.

[0060] The method for preparing the salt form of the coronavirus 3CL protease inhibitor (PLC-01) disclosed in this invention is simple, highly controllable, and easy for large-scale production.

[0061] The salt form combination containing the above-mentioned coronavirus 3CL protease inhibitor salt form provided by this invention provides a basic material for drug formulation development, helps to apply the inhibitor to actual drug production, provides a feasible drug raw material to overcome the limitations of existing crystal forms, and promotes the progress of drug development to clinical application.

[0062] The pharmaceutical compositions provided by this invention greatly expand the formulation options for drugs. Different excipients can impart different physical and chemical properties to drugs, such as improving drug solubility, stability, and flowability, enabling drugs to be formulated into various dosage forms such as tablets, capsules, injections, and oral liquids to meet the medication needs of different patients and clinical application scenarios.

[0063] The applications provided by this invention address the limitations of existing PLC-01 crystal forms, such as low solubility, poor stability, insufficient pharmacological activity, and the need to improve bioavailability and efficacy. The application of these salt forms, active pharmaceutical ingredients, and pharmaceutical compositions improves drug performance by altering the physical and chemical properties of the drugs, thereby better enabling them to play a role in preventing and treating novel coronavirus infection. This provides a scientific basis for the final market launch of the drugs and helps to improve the level of prevention and control of novel coronavirus infection. Attached Figure Description

[0064] Figure 1 The X-ray powder diffraction pattern (XRPD) of the free-state Pattern A crystal of PLC-01 of this invention;

[0065] Figure 2 Differential scanning calorimetry (DSC) analysis spectrum of the free-state Pattern A crystal of PLC-01 of this invention;

[0066] Figure 3 Thermogravimetric analysis (TGA) spectrum of the free-state Pattern A crystal of PLC-01 of this invention;

[0067] Figure 4 The Fourier transform infrared spectrum (FT-IR) of the free-state PatternA crystal of PLC-01 of this invention;

[0068] Figure 5 The free-state Pattern A crystal of PLC-01 of this invention 1 H NMR spectrum;

[0069] Figure 6 The X-ray powder diffraction pattern (XRPD) of the hydrochloride Pattern A crystal of PLC-01 of this invention is shown.

[0070] Figure 7 The differential scanning calorimetry (DSC) spectrum of the hydrochloride Pattern A crystal of PLC-01 of this invention is shown.

[0071] Figure 8 Thermogravimetric analysis (TGA) spectrum of the hydrochloride Pattern A crystal of PLC-01 of this invention;

[0072] Figure 9 The Fourier transform infrared spectrum (FT-IR) of the hydrochloride Pattern A crystal of PLC-01 of this invention;

[0073] Figure 10 The hydrochloride pattern A crystal of PLC-01 of this invention 1 H NMR spectrum;

[0074] Figure 11 The X-ray powder diffraction (XRPD) pattern of the methanesulfonate Pattern A crystal of PLC-01 of this invention;

[0075] Figure 12 The differential scanning calorimetry (DSC) spectrum of the methanesulfonate Pattern A crystal of PLC-01 of this invention is shown.

[0076] Figure 13 Thermogravimetric analysis (TGA) spectrum of the methanesulfonate Pattern A crystal of PLC-01 of this invention;

[0077] Figure 14 The Fourier transform infrared spectrum (FT-IR) of the methanesulfonate Pattern A crystal of PLC-01 of this invention;

[0078] Figure 15 The Methanesulfonate Pattern A crystal of PLC-01 of this invention 1 H NMR spectrum;

[0079] Figure 16 The X-ray powder diffraction (XRPD) pattern of the sodium salt Pattern C crystal of PLC-01 of this invention is shown.

[0080] Figure 17 The differential scanning calorimetry (DSC) spectrum of the sodium salt Pattern C crystal of PLC-01 of this invention is shown.

[0081] Figure 18 Thermogravimetric analysis (TGA) spectrum of sodium salt Pattern C crystal of PLC-01 of this invention;

[0082] Figure 19 The Fourier transform infrared spectrum (FT-IR) of the sodium salt Pattern C crystal of PLC-01 of this invention;

[0083] Figure 20 The sodium salt Pattern C crystal of PLC-01 of this invention 1 H NMR spectrum. Detailed Implementation

[0084] To enable those skilled in the art to understand the features and effects of the present invention, the following descriptions and definitions are only general descriptions of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in the event of any conflict, the definitions in this specification shall prevail.

[0085] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0086] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under standard conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications in the art, unless otherwise stated.

[0087] The instruments used in the reference embodiments of the present invention are as follows:

[0088] (1) X-ray powder diffractometer (XRPD, Bruker D8 Advance)

[0089] (2) Differential Scanning Calorimeter (DSC, TA Instruments Discovery 2500)

[0090] (3) Thermogravimetric analyzer (TGA, TA Instruments Discovery 5500)

[0091] (4) Fourier transform infrared spectroscopy (FT-IR, Thermo Nicolet iS5)

[0092] The coronavirus 3CL protease inhibitor of this invention is a compound of Formula I, namely (E)-3-((1H-1,2,3-triazol-5-yl)methyl)-6-((6-chloro-2-methyl-2H-indazol-5-yl)imino)-1-(2,4,5-trifluorobenzyl)-1,3,5-triazine-2,4-dione, abbreviated as PLC-01.

[0093]

[0094] PLC-01, as a 3CL protease inhibitor, exhibits strong inhibitory efficacy. Its inhibitory activity reaches the nanomolar level, and its in vitro 3CL protease inhibitory activity is close to that of the marketed drug Ensitrelvir, but it has better pharmacokinetic characteristics. I. Specific Implementation Methods

[0096] Example 1

[0097] This embodiment provides the free-state Pattern A salt form / crystal of the coronavirus 3CL protease inhibitor (PLC-01). The specific preparation steps are as follows (see CN202210618258.2): The structural formula of compound 1 is...

[0098]

[0099]

[0100] Compound 1 (177.7 mg, 0.5 mmol), 6-chloro-2-methyl-2H-indazole-5-amine (118.1 mg, 0.65 mmol), and acetic acid (570 μL, 10 mmol) were placed in a reactor and dissolved in 5 mL of tert-butanol. The mixture was stirred at 100 °C for 4 hours and monitored by TLC. After the reaction was completed, the mixture was cooled to room temperature, concentrated under reduced pressure, and purified by column chromatography using cyclohexane and ethyl acetate in a volume ratio of 10:1 as the mobile phase. The purified compound was dried to obtain 125.6 mg of the compound, with a yield of 52.90%, which was compound 2.

[0101]

[0102] Compound 2 (2.4 g, 5 mmol), azidotrimethylsilane (864.1 mg, 7.5 mmol), and cuprous iodide (47.6 mg, 0.25 mmol) were placed in a reactor and dissolved in a mixture of 90 mL N,N-dimethylformamide and 10 mL methanol. The mixture was heated and stirred overnight, and the reaction was monitored by TLC. After the reaction was completed, the mixture was cooled to room temperature, washed with saturated sodium chloride aqueous solution, extracted with ethyl acetate, and the organic phase was collected and purified by column chromatography (using dichloromethane:methanol (V:V) = 12:1 as the mobile phase). The purified organic phase was dried to give 1995.3 mg of the compound, with a yield of 38.44%, in the free state of PLC-01.

[0103] The free-state Pattern A obtained in this embodiment was tested by XRPD, DSC, TGA, FT-IR and 1H NMR.

[0104] See appendix Figure 1 The X-ray powder diffraction (XRPD) pattern of the free-state Pattern A salt type / crystal of PLC-01 shows that the free-state Pattern A has absorption peaks at 7.81°, 13.30°, 17.01°, 17.90°, 19.47°, 20.19°, 20.60°, 23.51°, 24.93°, 25.45°, 26.83°, 28.26°, and 30.35°.

[0105] See appendix Figure 2 The differential scanning calorimetry (DSC) spectrum of the free-state Pattern A salt form / crystal of PLC-01 shows that the free-state Pattern A has a broad dehydration peak, starting from about 70℃, and there is a relatively broad endothermic dehydration peak with a melting enthalpy of 159 J / g at 95℃.

[0106] See appendix Figure 3 The thermogravimetric analysis (TGA) spectrum of the free-state Pattern A salt form / crystal of PLC-01 shows that the free-state Pattern A loses 6.5% of its weight at 200℃.

[0107] See appendix Figure 4 The image shows the Fourier transform infrared (FT-IR) spectrum of the free-state Pattern A salt type / crystal of PLC-01. It can be seen that the free-state Pattern A is at 3316 cm⁻¹. -1 3164cm -1 3047cm -1 2904cm -1 2698cm -1 1676cm -1 1516cm -11451cm -1 1340cm -1 1218cm -1 1142cm -1 1066cm -1 959cm -1 875cm -1 845cm -1 779cm -1 738cm -1 679cm -1 634cm -1 598cm -1 There is an absorption peak at that point.

[0108] See appendix Figure 5 For PLC-01 free state Pattern A salt type / crystal 1 H NMR spectrum.

[0109] Example 2

[0110] This embodiment provides the coronavirus 3CL protease inhibitor (PLC-01) hydrochloride in Pattern A salt form / crystal, and the specific preparation process is as follows:

[0111] Weigh 299.7 mg of PLC-01 free-state PatternA and place it in a 20 mL glass bottle; add 3.0 mL of acetone and stir at 50 °C for 5 min to obtain suspension 1 (or turbid suspension 1); add 1.0 mL of hydrochloric acid-acetone solution (a mixed solution of hydrochloric acid and acetone, with hydrochloric acid as the counterion, mixed at a volume ratio of 1:2.1) to suspension 1 and stir for 2 h to obtain suspension 2 (or turbid suspension 2); allow suspension 2 to cool naturally to 25 °C and stir at 25 °C for about 3 days, then centrifuge through a 0.45 μm nylon filter membrane at 14,000 rpm, wash the filter cake twice with acetone, and dry the obtained solid under vacuum at 50 °C for 18 h, then under vacuum at 60 °C for 2 h to obtain 309.0 mg of white powder of PatternA hydrochloride, with a yield of 93%.

[0112] The hydrochloride pattern A prepared in this embodiment was subjected to XRPD, DSC, TGA, FT-IR and... 1 1H NMR test results are attached. Figures 6-10 As shown.

[0113] See appendix Figure 6The X-ray powder diffraction (XRPD) pattern of PLC-01 hydrochloride Pattern A salt form / crystal shows that Pattern A hydrochloride has absorption peaks at 8.01°, 14.09°, 15.95°, 17.02°, 20.24°, 21.04°, 21.40°, 21.96°, 23.38°, 24.76°, 25.51°, 25.83°, 28.37°, 30.87°, and 31.46°.

[0114] See appendix Figure 7 The differential scanning calorimetry (DSC) spectrum of PLC-01 hydrochloride Pattern A salt form / crystal shows that Pattern A hydrochloride begins with a broad dehydration endothermic peak at about 18℃ and melts at a Tonset of 143.9℃, with melting accompanied by dissociation.

[0115] See appendix Figure 8 The thermogravimetric analysis (TGA) spectrum of PLC-01 hydrochloride Pattern A salt form / crystal shows that the weight loss of hydrochloride Pattern A is 7.3% at 93℃ and about 6.5% between 93℃ and 180℃.

[0116] See appendix Figure 9 The image shows the Fourier transform infrared (FT-IR) spectrum of PLC-01 hydrochloride Pattern A salt form / crystal. It can be seen that Pattern A hydrochloride is at 3132 cm⁻¹. -1 2932cm -1 1729cm -1 1581cm -1 1506cm -1 1463cm -1 1428cm -1 1395cm -1 1331cm -1 1285cm -1 1246cm -1 1189cm -1 1151cm -1 1088cm -1 1027cm -1 994cm -1 930cm -1 886cm -1 782cm -1 749cm -1 691cm -1 651cm -1 584cm -1 There is an absorption peak at that point.

[0117] See appendix Figure 10 PLC-01 hydrochloride Pattern A salt type / crystal 1 H NMR spectrum.

[0118] Example 3

[0119] This embodiment provides the methanesulfonate Pattern A salt form / crystal of the coronavirus 3CL protease inhibitor (PLC-01), and the specific preparation process is as follows:

[0120] Weigh 300.3 mg of PLC-01 free Pattern A and place it in a 20 mL glass bottle; add 2.6 mL of ethanol and stir at 50 °C for 5 min to obtain suspension 1 (or turbidity 1); add 0.4 mL of methanesulfonic acid ethanol solution (1.10 eq) to the above suspension 1 and stir for 2 h to obtain suspension 2 (or turbidity 2); allow suspension 2 to cool naturally to 25 °C and stir at 25 °C for 3 days; centrifuge the obtained suspension through a 0.45 μm nylon filter membrane at 14,000 rpm; vacuum dry the obtained solid at 50 °C for 18 h and then vacuum dry at 60 °C for 3 h to obtain 316.9 mg of methanesulfonate Pattern A off-white powder, with a yield of 90%.

[0121] The PLC-01 methanesulfonate pattern A prepared in the examples was subjected to XRPD, DSC, TGA, FT-IR and... 1 For H NMR test results, please refer to the appendix. Figures 11-15 As shown.

[0122] See appendix Figure 11 The X-ray powder diffraction (XRPD) pattern of PLC-01 methanesulfonate Pattern A salt form / crystal shows that methanesulfonate Pattern A has absorption peaks at 6.75°, 7.32°, 14.81°, 16.59°, 18.51°, 19.14°, 19.42°, 21.07°, 22.36°, 22.95°, 25.89°, and 27.21°.

[0123] See appendix Figure 12 The differential scanning calorimetry (DSC) spectrum of PLC-01 methanesulfonate Pattern A (salt form / crystal) shows that PLC-01 methanesulfonate Pattern A has an endothermic peak for dehydration and desolvation at approximately 93 °C, and the peak is located at T... onset It melts at 206.8℃, with a melting enthalpy of approximately 85 J / g.

[0124] See appendix Figure 13The thermogravimetric analysis (TGA) spectrum of PLC-01 methanesulfonate Pattern A salt form / crystal shows that the methanesulfonate Pattern A loses 1.9% of its weight at 160℃.

[0125] See appendix Figure 14 The image shows the Fourier transform infrared (FT-IR) spectrum of the PLC-01 methanesulfonate Pattern A salt form / crystal. It can be seen that the methanesulfonate Pattern A is at 3109 cm⁻¹. -1 2960cm -1 2796cm -1 1753cm -1 1663cm -1 1559cm -1 1464cm -1 1385cm -1 1347cm -1 1291cm -1 1202cm -1 1138cm -1 1087cm -1 1040cm -1 1005cm -1 957cm -1 895cm -1 850cm -1 804cm -1 757cm -1 705cm -1 682cm -1 632cm -1 There is an absorption peak at that point.

[0126] See appendix Figure 15 PLC-01 methanesulfonate Pattern A salt type / crystal 1 H NMR spectrum.

[0127] Example 4

[0128] This embodiment provides a sodium salt of coronavirus 3CL protease inhibitor (PLC-01) in Pattern C salt form / crystal. The specific preparation steps are as follows:

[0129] Weigh 302.0 mg of PLC-01 free-state Pattern A and 45.84 mg of sodium hydroxide (2.10 eq) and place them in a 20 mL glass bottle; add 3.0 mL of acetone and stir at 50 °C for 2 h to obtain suspension 1 (or turbid suspension 1); add 0.4 mL of sodium hydroxide acetone solution (1:1.10 eq) to the above suspension 1 and stir for 2 h to obtain suspension 2 (or turbid suspension 2); allow suspension 2 to cool naturally to 25 °C and stir at 25 °C for 3 days; centrifuge the obtained suspension through a 0.45 μm nylon filter membrane at 14,000 rpm; and vacuum dry the obtained solid at 50 °C for 5 h. A total of 193 mg of sodium salt Pattern C white powder was obtained, with a yield of 60%.

[0130] The PLC-01 sodium salt pattern C prepared in this embodiment was tested by XRPD, DSC, TGA, FT-IR and 1H NMR. Specific results are shown in the appendix. Figures 16-20 As shown.

[0131] See appendix Figure 16 The X-ray powder diffraction (XRPD) pattern of sodium salt C-type / crystal of PLC-01 is shown below. Figure 16 It can be seen that the sodium salt Pattern C has absorption peaks at 9.21°, 9.46°, 11.02°, 13.17°, 16.55°, 17.66°, 18.42°, 21.04°, 22.10°, 25.70°, and 26.52°.

[0132] See appendix Figure 17 The differential scanning calorimetry (DSC) spectrum of sodium salt pattern C salt type / crystal of PLC-01 is obtained from... Figure 17 It can be seen from the pattern C of sodium salt that there is a broad endothermic peak for dehydration and desolvation starting at about 5℃ and continuing at T onset It melts at 100.8℃, and melting is accompanied by decomposition.

[0133] See appendix Figure 18 The thermogravimetric analysis (TGA) spectrum of the sodium salt Pattern C salt form / crystal of PLC-01 shows that the sodium salt Pattern C loses 3.2% of its weight at 90℃ and about 4.6% of its weight between 90℃ and 220℃.

[0134] See appendix Figure 19 The image shows the Fourier transform infrared (FT-IR) spectrum of the sodium salt Pattern C salt form / crystal of PLC-01. It can be seen that the sodium salt Pattern C is at 1695 cm⁻¹. -1 1568 cm -1 1482 cm-1 1408 cm -1 1364 cm -1 1307 cm -1 1269 cm -1 1200 cm -1 1090 cm -1 1005 cm -1 839 cm -1 793 cm -1 745 cm -1 708cm -1 677 cm -1 652 cm -1 580 cm -1 There is an absorption peak at that point.

[0135] See appendix Figure 20 The sodium salt pattern of PLC-01 is in C salt form / crystal. 1 H NMR spectrum.

[0136] II. Performance Testing

[0137] Based on Examples 1-5, the performance of the salt form of the coronavirus 3CL protease inhibitor (PLC-01) prepared in the embodiments of the present invention was tested.

[0138] (1) Solid stability verification

[0139] Open containers containing free Pattern A, hydrochloride Pattern A, methanesulfonate Pattern A, and sodium salt Pattern C were placed at 25℃ / 60%RH, 25℃ / 92%RH, and 40℃ / 75%RH for one week, respectively. Closed containers containing free Pattern A, hydrochloride Pattern A, methanesulfonate Pattern A, and sodium salt Pattern C were placed at 60℃ for one week. The samples were characterized by XRPD and HPLC after solid stability assessment, and color changes were observed. It was found that PLC-01 hydrochloride Pattern A and PLC-01 free pattern A exhibited the best physical stability.

[0140] Table 1: Stability, Purity, and Appearance

[0141]

[0142]

[0143] Note A: No color change; B: Slight color change; C: Moderate color change; D: Severe color change

[0144] (2) Hygroscopicity test

[0145] The hygroscopicity of the four salt forms at 25°C was evaluated by DVS. The results are shown in Tables 2 and 3. The results showed that PLC-01 free state Pattern A had the best hygroscopic stability.

[0146] Table 2: Hygroscopicity test

[0147]

[0148]

[0149] Table 3: Hygroscopicity test

[0150]

[0151] Note " / / ": Not carried out;

[0152]

[0153] Water absorption = Water absorption at a specific RH level (80% to 95%) - Water absorption at 40% RH level

[0154] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A salt form of a coronavirus 3CL protease inhibitor, characterized in that, The structural formula of the coronavirus 3CL protease inhibitor is shown in Formula I. The salt crystal is a free Pattern A crystal and an acid addition salt crystal or a base addition salt crystal. The acid addition salt crystal is selected from either the hydrochloride Pattern A or the methanesulfonate Pattern A. The base addition salt crystal is the sodium salt Pattern C. The free-state Pattern A crystal, when subjected to Cu-Kα radiation, exhibits characteristic diffraction peaks in its X-ray powder diffraction pattern, expressed as 2θ values ​​±0.2°, including: 7.81±0.2°, 13.30±0.2°, 17.01±0.2°, 17.90±0.2°, 19.47±0.2°, 20.19±0.2°, 20.60±0.2°, 23.51±0.2°, 24.93±0.2°, 25.45±0.2°, 26.83±0.2°, 28.26±0.2°, and 30.35±0.2°. The characteristic diffraction peaks of the X-ray powder diffraction pattern of the Pattern A hydrochloride crystal, expressed as 2θ value ±0.2°, using Cu-Kα radiation, include: 8.01±0.2°, 14.09±0.2°, 15.95±0.2°, 17.02±0.2°, 20.24±0.2°, 21.04±0.2°, 21.40±0.2°, 21.96±0.2°, 23.38±0.2°, 24.76±0.2°, 25.51±0.2°, 25.83±0.2°, 28.37±0.2°, 30.87±0.2°, and 31.46±0.2°. The characteristic diffraction peaks of the X-ray powder diffraction pattern of the methanesulfonate Pattern A crystal, expressed as 2θ value ±0.2°, are as follows: 6.75±0.2°, 7.32±0.2°, 14.81±0.2°, 16.59±0.2°, 18.51±0.2°, 19.14±0.2°, 19.42±0.2°, 21.07±0.2°, 22.36±0.2°, 22.95±0.2°, 25.89±0.2°, 27.21±0.2°. The characteristic diffraction peaks of the X-ray powder diffraction pattern of the sodium salt Pattern C crystal, expressed as 2θ value ±0.2°, using Cu-Kα radiation, include: 9.21±0.2°, 9.46±0.2°, 11.02±0.2°, 13.17±0.2°, 16.55±0.2°, 17.66±0.2°, 18.42±0.2°, 21.04±0.2°, 22.10±0.2°, 25.70±0.2°, and 26.52±0.2°.

2. The salt form of the coronavirus 3CL protease inhibitor according to claim 1, characterized in that, The free-state Pattern A crystal also has one or more characteristics selected from the group consisting of: (1) The differential scanning calorimetry (DSC) spectrum of the free-state Pattern A crystal shows a broad dehydration peak; and / or (2) The thermogravimetric analysis spectrum of the free-state Pattern A crystal shows a weight loss of 6.5% when heated to 200℃; and / or (3) The free-state Pattern A crystal absorbs moisture and gains 0.5% weight in an environment of 25°C and 40% to 95% humidity; and / or (4) The FT-IR spectrum of the free-state Pattern A crystal has the following characteristic absorption peak, represented by wavelength λ: 3316±2cm -1 3164±2cm -1 3047±2cm -1 2904±2cm -1 2698±2cm -1 1676±2cm -1 1516±2cm -1 1451±2cm -1 1340±2cm -1 1218±2cm -1 1142±2cm -1 1066±2cm -1 959±2cm -1 875±2cm -1 845±2cm -1 779±2cm -1 738±2cm -1 679±2cm -1 634±2cm -1 598±2cm -1 ; and / or (5) The free-state PatternA crystal is an irregular particle formed by the aggregation of tiny crystal aggregates with a particle size of 10 to 100 μm.

3. The salt form of the coronavirus 3CL protease inhibitor according to claim 1, characterized in that, The hydrochloride Pattern A crystal also has one or more characteristics selected from the group consisting of: (1) The differential scanning calorimetry (DSC) analysis spectrum of the Pattern A hydrochloride crystal shows a melting peak after dehydration, and the melting is accompanied by dissociation; and / or (2) The thermogravimetric analysis of the hydrochloride pattern A showed a weight loss of 7.3% when heated to 93°C and a weight loss of 6.5% during the process from 93°C to 180°C; and / or (3) The hydrochloride pattern A absorbs moisture and gains approximately 4.3% weight at 25°C and 40% to 80% humidity; and approximately 12.4% weight at 25°C and 80% to 95% humidity; and / or (4) The FT-IR spectrum of the hydrochloride pattern A has the following characteristic absorption peak, expressed in wavelength λ: 3132±2 cm⁻¹ -1 2932±2cm -1 1729±2cm -1 1581±2cm -1 1506±2cm -1 1463±2cm -1 1428±2cm -1 1395±2cm -1 1331±2cm -1 1285±2cm -1 1246±2cm -1 1189±2cm -1 1151±2cm -1 1088±2cm -1 1027±2cm -1 994±2cm -1 930±2cm -1 886±2cm -1 782±2cm -1 749±2cm -1 691±2cm -1 651±2cm -1 584±2cm -1 ; and / or (5) The hydrochloride pattern A is an irregular particle formed by the aggregation of tiny crystal aggregates with a particle size of 2 to 10 μm.

4. The salt form of the coronavirus 3CL protease inhibitor according to claim 1, characterized in that, The methanesulfonate Pattern A crystal also has one or more characteristics selected from the group consisting of: (1) The differential scanning calorimetry (DSC) analysis of the methanesulfonate Pattern A crystals showed a melting peak after dehydration; and / or (2) The thermogravimetric analysis of the methanesulfonate Pattern A crystal showed a weight loss of 1.9% when heated to 160°C; and / or (3) The methanesulfonate Pattern A crystals, when placed in an environment of 25°C and 40% to 80% humidity, showed a moisture absorption weight gain of 3.6%; when placed in an environment of 25°C and 80% to 95% humidity, the moisture absorption weight gain was 84.3%; and / or (4) The FT-IR spectrum of the methanesulfonate Pattern A crystal has the following characteristic absorption peak, expressed in wavelength λ: 3109±2cm -1 2960±2cm -1 2796±2cm -1 1753±2cm -1 1663±2cm -1 1559±2cm -1 1464±2cm -1 1385±2cm -1 1347±2cm -1 1291±2cm -1 1202±2cm -1 1138±2cm -1 1087±2cm -1 1040±2cm -1 1005±2cm -1 957±2cm -1 895±2cm -1 850±2cm -1 804±2cm -1 757±2cm -1 705±2cm -1 682±2cm -1 632±2cm -1 ; and / or (5) The methanesulfonate Pattern A crystals are irregular particles formed by the aggregation of tiny crystal aggregates with a particle size of 2 to 10 μm.

5. The salt form of the coronavirus 3CL protease inhibitor according to claim 1, characterized in that, The sodium salt Pattern C crystal also has one or more characteristics selected from the group consisting of: (1) The differential scanning calorimetry (DSC) spectrum of the sodium salt Pattern C crystal shows a melting peak after dehydration, and the melting is accompanied by dissociation; and / or (2) The thermogravimetric analysis (TGA) spectrum of the sodium salt Pattern C crystal showed a weight loss of 3.2% at 90℃ and approximately 4.6% between 90℃ and 220℃; and / or (3) The sodium salt Pattern C crystals, when placed at 25°C and with a humidity of 40% to 80%, absorb moisture and gain 32.0% in weight; when placed at 25°C and with a humidity of 80% to 95%, absorb moisture and gain 57.0% in weight; and / or (4) The FT-IR spectrum of the sodium salt Pattern C crystal has the following characteristic absorption peak, represented by wavelength λ: 1695±2cm. -1 1568±2cm -1 1482±2cm -1 1408±2cm -1 1364±2cm -1 1307±2cm -1 1269±2cm -1 1200±2cm -1 1090±2cm -1 1005±2cm -1 839±2cm -1 793±2cm -1 745±2cm -1 708±2cm -1 677±2cm -1 652±2cm -1 580±2cm -1 ; and / or (5) The sodium salt Pattern C crystal is an irregular particle formed by the aggregation of tiny crystal aggregates with a particle size of 2 to 10 μm.

6. A method for preparing the salt form of the coronavirus 3CL protease inhibitor according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Dissolve the coronavirus 3CL protease inhibitor described in Formula 1, heat and stir to obtain suspension 1; (2) Add solution 2 to the suspension 1 obtained in step (1) and stir to obtain suspension 2; the solution 2 is an acid solution or an alkaline solution, and the acid solution includes organic acid and inorganic acid solutions; (3) After the suspension 2 obtained in step (2) is cooled naturally, it is stirred, centrifuged, washed, and vacuum dried to obtain the salt form of coronavirus 3CL protease inhibitor.

7. A salt-type combination, characterized in that, The salt combination comprises at least two of the following salt forms as described in claim 1: hydrochloride Pattern A, methanesulfonate Pattern A, sodium salt Pattern C, and free Pattern A.

8. A salt-type combination according to claim 7, characterized in that, Based on the total weight of the salt combination, the total mass percentage of hydrochloride Pattern A, methanesulfonate Pattern A, sodium salt Pattern C, and free Pattern A is 60-99.999%.

9. A pharmaceutical composition, characterized in that, It comprises a salt form of the coronavirus 3CL protease inhibitor according to any one of claims 1 to 5, and one or more pharmaceutically acceptable excipients.

10. The use of a salt form of the coronavirus 3CL protease inhibitor according to any one of claims 1 to 5, or a combination of salt forms according to claim 7 or 8, or the pharmaceutical composition according to claim 9 in the preparation of a drug for the prevention or treatment of novel coronavirus infection.

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