EA014043B1 - Purine derivatives - Google Patents

Abstract

The invention discloses purine derivatives of formula (II), including pharmaceutically-acceptable solvate or hydrate thereof, wherein M<-> represents a pharmaceutically-acceptable acid anion. It also relates to the preparation of such compounds, pharmaceutical compositions containing them and the use of such compounds for the treatment of hepatitis B viral infections and/or concurrent infections in human being.

Description

FIELD OF THE INVENTION

The present invention relates to new derivatives of purine, their preparation and pharmaceutical compositions containing these compounds, and the use of data. compounds for the treatment of hepatitis B virus infections and / or concomitant infections.

State of the art

American patent (C8 5206244) describes a compound of formula (I) and its antiviral activity, especially activity in preventing hepatitis B virus infections. Chinese patent application (CU 1310969) describes a pharmaceutical composition comprising a low dosage of a compound of formula (I)

Solubility of Compound (I), [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine - 6-it is less than 2.5 mg / ml both in aqueous solution and / or in neutral physiological buffer solution at room temperature, which refers to an insoluble compound. Low solubility usually increases the complexity of manufacturing a pharmaceutical preparation and prevents the rapid release of the active component from the drug, and also affects the production of other drugs or preparations for parenteral administration, for example, the production of a solid preparation for oral administration. Therefore, increasing the solubility of an insoluble drug is important to increase the effect and expand the range of drugs from insoluble drugs, which is also advisable to reduce the cost of obtaining it.

Disclosure of invention

The aim of this invention is the discovery of new derivatives of purine and their salts having good solubility in water and stability in a finely divided solid state, for a substantially convenient and effective industrial production of an oral preparation or dosage form.

The compound of formula (I) was investigated by experimental methods of creating a drug molecule. It was found that the charge density of the nitrogen atom of the 2-amino group in the purine ring is 0.53, and the pKb is only 4.31. These data showed that the compound of formula (I) cannot form an acid salt with any acid anion.

In this invention, acid salts of a compound of formula (I) with certain inorganic acids were studied, including hydrobromic acid (pKa = -9), hydrochloric acid (pKa = -7), sulfuric acid (pKa = -7), nitric acid (pKa = -1.64), phosphoric acid (pKa = 2.12), carbonic acid (pKa = 3.88). It was found that the compound of formula (I) can react with hydrobromic acid, hydrochloric acid, sulfuric and nitric acids to form stable salts. Whereas under the same conditions the salt formed with phosphoric acid was unstable, and the compound did not react with carbonic acid to form a stable salt. In this invention, salts of acids of a compound of formula (I) with some organic acids were also studied, including methanesulfonic acid (pKa = 0.5), maleic acid (pKa = 1.92), tartaric acid (pKa = 2.98), fumaric acid (pKa = 3.02), citric acid (pKa = 3.13), malic acid (pKa - 3.4), lactic acid (pKa = 3.86) and acetic acid (pKa = 4.75). It has been found that a compound of formula (I) can react with methanesulfonic acid, maleic acid, tartaric acid, fumaric acid and citric acid to form a stable salt. Whereas under the same conditions the salts formed with malic acid, lactic and acetic acids were not stable. Obviously, it is impossible to predict whether the compound of formula (I) can form stable acid salts.

Therefore, the present invention relates to stable derivatives of purine of the formula (II)

- 1 014043 where M ^is a pharmaceutically acceptable acid anion;

acid anion M ^- selected from an inorganic acid with a pKa of less than 2.0 or an organic acid with a pKa of less than 3.5.

According to this invention, inorganic acids with pKa of less than 2.0 include hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, nitric acid, etc.

Organic acids with pKa less than 3.5 include methanesulfonic acid, maleic acid, tartaric acid, fumaric acid, citric acid, oxalic acid, etc.

As claimed by the invention, the preferred compounds of formula (II) are [18- (1α, 3α, 4β)] -2-amino-1,9-dihydro-9- [4-hydroxy-3 - (hydroxymethyl) -2-methylenecyclopentyl] -6Npurin-6-one hydrochloride;

[18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6Npurin-6-one methanesulfonate and [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6Npurin-6-one maleate.

In the present invention, the compounds of formula (II) also include their corresponding pharmaceutically acceptable solvates and / or hydrates.

In the present invention, the compounds of formula (II) have a much higher solubility than the compound of formula (I) under the same conditions. For example, in an aqueous solution and in a neutral physiological buffer solution at room temperature, the solubility of the compound of formula (II) [18 (1a, 3a, 4c) -2-amino-1,9-dihydro-9- [4-hydroxy-3- ( hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6one hydrochloride is more than 165 mg / ml, and the solubility of the compounds of formula (II) [18 (1a, 3a, 4c)] is 2-amino-1,9-dihydro 9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6one maleate monohydrate is 14.1 mg / ml. While under the same conditions, the solubility of the compounds of formula (I) is 2.4 mg / ml. The solubility of the compounds of formula (II) is markedly improved, from 5 to 68 times compared with the solubility of the compounds of formula (I). The markedly improved solubility provides good medical uses for the compound of formula (II), such as the quick release from a solid preparation or the bioavailability of the substance, and greatly and efficiently facilitates the production of various types of preparations for oral administration or other drugs.

In addition, the compounds of formula (II) have good stability in the solid state and in solution, especially in aqueous solution. For example, the compound of formula (II) [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- (4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6 -one maleate or its monohydrate is destroyed at high temperature or under destructive experimental conditions, such as in water at 100 ° C, in 0.1 M hydrochloric acid at 100 ° C or in a 0.1 M aqueous NaOH solution at 100 ° C in within 24 hours. The results show that the sample remains stable in water at 100 ° C, and the decomposition product is less than 2% by HPLC analysis. in industry for the production of various types of preparations for oral administration, especially for the production of a drug or a dosage form for oral administration.

More specifically, the compounds of formula (II) also have good processability, and they are stable crystalline compounds with a high melting point. In the solid state, they are very loose and have good fluidity. Consequently, they can be produced and processed on a large scale in industry, especially during processing in which heat is absorbed or heat is generated, such as grinding, drying by heat, drying in a fluidized bed, spray drying, sterilization at high pressure and high temperature. Therefore, the compound of formula (II) can be produced efficiently, economically and conveniently, especially on a large scale in industry.

The compounds of formula (II) are acid salts of the compounds of formula (I). The invention relates to all forms of salts, especially acid salts, formed by the association of the nitrogen atom of a 2-amino group in the purine ring of a compound of formula (I) with an acid anion.

The invention further relates to a process for preparing a compound of formula (II) and / or a pharmaceutically acceptable solvate and / or hydrate thereof. The compound of formula (I) can be obtained according to the method described in the literature (Wassa et al., Vyuguds & Meb1st1 Syetzhyu Leyega, Wo1. 7, Vos. 2, pp. 127-132, 1997). The compound of formula (I) reacts with an equivalent or slightly larger excess of M anion ^- under acidic conditions, usually in a solvent such as C1-6 lower alcohol solvent (such as methanol) or in an aqueous solution at any temperature that corresponds to an appropriate reaction rate, usually at room temperature or high temperature, such as the boiling point of the solvent. The product can then crystallize from a suitable solvent, for example a lower alkyl ketone such as acetone, usually cooling can accelerate crystallization. A pharmaceutically acceptable solvate and / or hydrate of the compound of formula (II) may

- 2 014043 be prepared by the usual chemical method.

The structure of the compound of formula (II) is established by NMR, MS, UV and IR spectra, thermogravimetric analysis (TGA) and X-ray diffraction on a single crystal, mainly ¹ H NMR and IR. For example, the infrared spectrum shows that when the compound of formula (I) turns into its salts, the characteristic vibrational peaks of its functional group, especially the characteristic vibrational peaks of the 2-amino group in the purine ring, are obviously shifted. For example, the chemical shift of the proton at the 2-amino group of the purine ring in the compound of formula (I) is 6.4 ppm, compared to 7.2 ppm. in its hydrochloride and 7.04 ppm in its methanesulfonate. The chemical shift of the proton in 1-nitrogen of the purine ring is 10.5 ppm. in the compound of formula (I), compared with 11.7 ppm. in its hydrochloride and 11.4 ppm in its methanesulfonate. FIG. from 4 to 6 are NMR spectra of the compounds of formula (I) and the hydrochloride and methanesulfonate compounds of the formula (II), respectively.

Basically, the present invention relates to the following objects of the invention:

1) the actual monohydrate [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2methylene-cyclopentyl] -6H-purine-6- onamaleate;

2) a pharmaceutical composition having antiviral activity, containing the monohydrate [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] 6H-purin-6-one maleate and a pharmaceutically acceptable carrier;

3) a method for producing monohydrate [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6 -one maleate, which includes the reaction of one equivalent or a slight excess of maleic acid as a source of anion M ^- with [18 (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3 - (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6one in methanol or water at room temperature to give [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy -3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate by crystallization followed by conversion pushing this compound into its hydrate;

4) a method for producing a pharmaceutical composition containing monohydrate [18- (1α, 3α, 4β)] - 2amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine -6-one maleate as an active ingredient, which comprises mixing an effective amount of the active ingredient with a pharmaceutically acceptable carrier;

5) the use of monohydrate [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) 2-methylenecyclopentyl] -6H-purin-6-one maleate in the manufacture of a medicament for the treatment of hepatitis B virus infection and / or concomitant infection.

Brief Description of the Figures

FIG. 1 is an IR spectrum of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3 (hydroxymethyl) -2-methylenecyclopentyl-3-6H-purin-6 -she;

FIG. 2 - IR spectrum of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2methylene cyclopentyl] -6H-purin-6-one hydrochloride ;

FIG. 3 - IR spectrum of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2methylene cyclopentyl] -6H-purin-6-one methanesulfonate ;

FIG. 4 - ¹ N ΝΜΚ. spectrum of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2methylenecyclopentyl] -6H-purin-6-one;

FIG. 5 - spectrum ¹ H ΝΜΚ. [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2methylenecyclopentyl] -6H-purin-6-one hydrochloride;

FIG. 6 - ¹ H NMR spectrum [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2methylene cyclopentyl] -6H-purine-6- she is methanesulfonate;

FIG. 7 - X-ray diffraction on a single crystal [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6- she is maleate.

A suitable M anion ^is derived from acids that are generally known and may be commercially available, such as hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, nitric acid, methanesulfonic acid, maleic acid, tartaric acid, fumaric acid., citric acid and oxalic acid, or can be prepared by some known methods.

According to this invention, the solubility of the compounds of the present invention can be determined in the usual way. For example, in a saturated aqueous solution at room temperature (25 ± 0.5 ° C), the solubility of the hydrochloride compound of formula (II) is more than 165 mg / ml, and the methanesulfonate compound is more than 200 mg / ml, while under the same conditions the solubility of the compound of formula (I) is 2.4 mg / ml. Compared to the compound of formula (I), the solubility of the compound of formula (II) is significantly improved in aqueous solution and in neutral physiological buffer solution. Such good solubility provides an advantage in the bioavailability of a compound of formula (II), as well as in the efficient production of an oral preparation containing a compound of formula II on a large scale.

According to this invention, the compound of formula (II) has good stability in solid

- 3 014043 condition, and stability can be measured by the usual method of quantitative analysis. For example, the stability of a compound of formula (II) can be measured by an accelerated stability test, for example, at 40 ° C, 75% relative humidity; at 40 ° C, relative humidity 92.5%; as well as at 80 ° C. The analysis can be done using HPLC, thin layer chromatography, differential scanning calorimetry (E8C), thermogravimetric analysis (TCA) and isothermal experiment with increasing temperature. A sample for quantitative analysis is taken before, during and after storage, respectively.

The invention also provides a compound; formula (II) and / or its pharmaceutically acceptable solvate or hydrate for the treatment of hepatitis B virus infections and / or concomitant infections.

The invention also relates to a pharmaceutical composition comprising a compound of formula (II) and / or its solvates or hydrate and a pharmaceutically acceptable carrier. The pharmaceutical composition can be administered in many forms, for example, in an oral tablet, capsule, powder, oral liquid, injection, transdermal preparation. According to a pharmaceutical convention, a pharmaceutically acceptable carrier includes a diluent, a bulking agent, a disintegrant, a wetting agent, a glidant, a coloring agent, a flavoring agent, and other conventional additives. A typical pharmaceutically acceptable carrier includes, but is not limited to, microcrystalline cellulose, starch, crospovidone, povidone, polyvinylpyrrolidone (RUR), maltol, citric acid, sodium dodecyl sulfonate (8-8) and magnesium stearate.

According to the invention, the compound of formula (II) has a markedly improved solubility and good stability, especially in aqueous solution. The pharmaceutical composition may be formulated for oral administration, usually containing from 0.001 to 50 mg, preferably from 0.01 to 10 mg, more preferably from 0.05 to 1 mg of the compound of formula (II). The liquid dosage form for oral administration may be a solution, syrup or emulsion. It can also be administered with a dry product that is mixed with water before applying the dry product. The liquid dosage form for oral administration may contain a conventional additive, such as maltol, sorbitol, syrup, gelatin, carboxyl methyl cellulose, citrate and phosphate, if required, it may also contain a flavoring or coloring agent.

The invention also relates to a method for treating hepatitis B virus infections and / or concomitant infections, which comprises administering to a patient with hepatitis B virus infections and / or concomitant infections in need of treatment, a therapeutically effective amount of a pharmaceutical composition containing a compound of formula (II) and / or its a pharmaceutically acceptable solvate or hydrate. The pharmaceutical composition is administered once a day and preferably comprises from 0.1 to 1 mg, more preferably 0.5 mg of the compound of formula (II). The pharmaceutical composition can be administered once a day to treat an adult patient with hepatitis B virus infection and / or concomitant infections.

The implementation of the present invention

The following examples are used only to illustrate the invention, but do not imply any limitation of the present invention.

Example 1. [18- (1a, 3a, 4c) -2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one hydrochloride .

2.77 g (0.01 mol) [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro [4-hydroxy-3- (hydroxymethyl) -2methylenecyclopentyl] -6H-purine- 6-it is placed in a 500 ml round bottom flask and 150 ml of methanol are added to dissolve the solid, followed by filtration. A methanolic solution of hydrochloric acid (12.0 M hydrochloric acid, 0.83 ml, 0.01 mol dissolved in 10 ml of methanol) was added to the filtrate, and the mixture was stirred until homogeneous. The solution was evaporated under reduced pressure to remove most of the methanol, and then acetone (150 ml) was added to the residue. When the solution was standing, crystals formed that were filtered off, washed with a small amount of acetone and dried at 40 ° C in vacuo to obtain 2.85 g of the indicated substance (90.2%).

IR ν cm ^-1 (KBr): 3365.0, 3164.1, 3126.6, 3062.2, 3015.6, 2916.0, 2876.4, 1701.2.1638.7, 1595.2.1468 0, 1360.1,1169.3, 1049.8, 1028.9, 778.0, 670.7.

Ή-NMR (600 MHz, ΌΜδΟ-άβ) δ ppm: 11.70 (s, 1H), 8.96 (s, 1H), 7.26 (s, 2H), 5.49-5.46 ( q, 1H), 5.22 (s, 1H), 4.83 (s, 1H), 4.26 ~ 4.25 (t, 1H), 3.59-3.53 (m, 2H), 2 55 (t, 1H), 2.33-2.29 (m, 1H), 2.16-2.12 (m, 1H), 2.09 ~ 1.99 (m, 1H).

MS t / e: 277.1 [M] ⁺ , 260.1, 246.1 [100], 229.1, 216.1, 204.1, 151.1, 152.1, 135.0, 109, 0, 95.1, 81.1, 67.1.

Example 2. [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one methanesulfonate.

2.77 g (0.01 mol) [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] - 6H-purin-6-one was placed in a 500 ml round bottom flask and 150 ml of methanol was added to dissolve the solid, followed by filtration. To the filtrate was added a methanolic solution of methanesulfonic acid (0.98 g of methanesulfonic acid, 0.01 mol dissolved in 10 ml of methanol). The mixture was stirred until homogeneous, and the solution was evaporated under reduced pressure.

- 4 014043 to remove most of the methanol. Then, 150 ml of acetone is added to the residue. When the solution was standing, crystals formed that were filtered off, washed with a small amount of acetone and dried at 40 ° C in vacuo to obtain 3.2 g of the indicated substance (85.6%).

IR ν cm ^-1 (KBr): 3396.07, 1573.65, 1407.8, 1342.23, 1209.16, 1051.03, 1018.24, 921.82, 649.90.

¹ H NMR (600 MHz, ΌΜ8Θ-ά ₆ ) δ ppm: 11.42 (s, 1H), 8.93 (s, 1H), 7.04 (w, 2H), 5.49 ~ 5 46 (q, 1H), 5.22 (s, 1H), 4.82 (s, 1H), 4.25 (w, 1H), 3.59 ~ 3.54 (m, 2H), 2, 54 (t, 1H), 2.37 (s, 3H), 2.32 ~ 2.28 (s, 1H), 2.15-2.12 (m, 1H).

MS t / e: 277, [Μ ⁺ ], 260.1, 246.1, 229.1, 216.1, 204.1, 151.1 [100], 152.0, 146.0, 135.0 , 109.0, 96.0, 91.0, 81.0, 69.0.

Example 3. [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate.

1.21 g of maleic acid (0.011 mol) and 30 ml of water are placed in a 100 ml round bottom flask. After dissolving maleic acid, 2.77 g (0.01 mol) of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2- are added methylenecyclopentyl] -6H-purin-6-one. The mixture was stirred while heating to form a homogeneous solution, and then 15 ml of acetone was added. When the solution was standing, crystals formed that were filtered off, washed with a small amount of acetone and dried at 40 ° C in vacuo to obtain 3.19 g of the indicated substance (82.3%).

IR ν cm ^-1 (KBr): 3380.07, 3141.5, 1691.29, 1571.72, 1405.87, 1307.52, 1052.96, 1018.24.8.63.96.649.90.

'|| NMR (600 MHz, ΌΜ8Θ-ά ₆ ) δ ppm: 13.25 (s, 1H), 10.68 (s, 1H), 7.83 (s, 1H), 7.04 (w, 2H) ), 6.50 (s, 2H), 6.25 (s, 2H) 5.40-5.35 (q, 1H), 5.12 (s, 1H), 4.93 (w, 1H), 4.83 (s, 1H), 4.59 (s, 1H), 4.23 (s, 1H), 3.54-3.52 (m, 2H), 2.52 (t, 1H), 2 26 ~ 2.19 (m, 1H); 2.07 ~ 2.02 (m, 1H).

MS t / e: 277.2, 259.1, 246.1 [100], 229.1, 216.1, 204.1, 152.0, 151.1, 135.1, 109.1, 95, 1, 81.1, 69.1.

Example 4. [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate monohydrate.

1.44 g of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H- are placed in a conical flask purin-6-one maleate (prepared according to example 3) and 5 ml of water. The solid is dissolved by heating. After cooling to room temperature, the solution was left overnight at 0 ~ 5 ° C, and crystals formed, which were filtered off and dried to constant weight to form 1.38 g of the title compound (93.2%) as white crystals.

Elemental analysis: С1 ₂ Н ₁₅ М5Оз-С ₄ Н ₄ О ₄ -Н ₂ О (calculated,%): С 46.72, Н 5.15, N 17.02; measured values,%: C 46.81, H 5.16, N 16.82.

IR ν cm ^-1 (KBr): 3446.5, 3366.3, 3294.9, 2949.2, 2856.6, 2704.2, 1724.3, 1630.1, 1599.5, 1539.5, 1485 7, 1396.5, 1061.2, 1014.6.

'|| NMR (600 MHz, ΌΜ8Ο ~ ά ₆ ) δ ppm: 10.56 (s, 1H), 7.66 (s, 1H), 6.41 (s, 2H), 5.38-5.35 (8.1H), 5.11 ~ 5.10 (t, 1H), 4.87 (d, 1H), 4.84 ~ 4.82 (t, 1H}, 4.57 ~ 4.56 (1 ,, 1H), 4.239-4.236 (m, 1H), 3.55 ~ 3.53 (q, 1H), 2.54-2.52 (t, .1H), 2.25-2.20 (m , 1H), 2.06 ~ 2.03 (m, 1H).

MS t / e: 277.2 [M ⁺ free base], 259.2, 246.2 [100], 242.0, 229.2, 152.0, 151.1, 135.1, 109.1, 95.1, 69.1.

TGA analysis: when heated, the indicated compound began to lose its mass at 75.9 ~ 88.3 ° С, and the rate of weight loss was 4.60%, which was equal to the calculated value of 4.3% in accordance with the indicated compound (С ^ Н (COOLDO-HdO), corresponding to one molecule of crystallization water.

Example 5. Determination of the stability of [18- (1a, 3a, 4c)] - 2-amines: but-1,9-dihydro-9- [4-hydroxy-3 (hydroxymethyl) -2-methylenecyclopentyl) -6H-purine - 6-one maleate monohydrate.

[18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6Npurin-6-one maleate monohydrate is placed in an oven at 80 ° C. Samples were taken on the 0th, 15th and 45th day for quantitative analysis on American HP 1100 HPBC. The chromatographic column was Раск ^ Rask OE8-L 3μ 4.6x150 mm, the mobile phase was 0.01 M KN ₂ PO ₄ : acetonitrile (94.5: 5.5), the flow rate was 1 ml / min, the detector wavelength was 254 nm, and the contents of all samples were calculated by the method of normalizing the area. The measurement results showed that the content of all samples is more than 99%, the decomposition product was less than 1%. Thus, the stability of the samples was good in an accelerated experiment at high temperature.

Example 6. Determination of hydroscopic stability [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6- it is maleate monohydrate.

[18- (1a, 3a, 4c) -2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6Nurin-6-one maleate monohydrate is placed in a desiccator with saturated KNΟ ₃ solution (relative humidity 92.5%) and saturated No. 101 solution (relative humidity 75%) at a constant temperature of 40 ° С, respectively. Samples taken on the 0th, 15th, 30th days were studied on the American HP 1100 HPLC. The chromatographic column was ΥΜC-Rask OE8-L 3μ 4.6x150 mm, the mobile phase was 0.01 M KH ₂ PO ₄ : acetonitrile (94.5: 5.5), the flow rate was 1 ml / min, the detector wavelength was 254 nm, and the contents of all samples were calculated by the method of area normalization. The measurement results showed that all sample contents were more than 99%, product times

- 5 014043 deposits was less than 1%. Thus, the stability of the samples was good at high humidity.

Example 7. Determination of the stability of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6 -one maleate monohydrate under destructive conditions.

In three vessels, each of which contained a sample of 10 mg [18- (1a, 3a, 4p)] - 2-amino-1,9-dihydro-9 [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate monohydrate, respectively, add 10 ml of 0.1Ν HCl, 10 ml of 0.1Ν ΝαΟΗ and 10 ml of neutral water. The vessels are sealed and heated in a thermostat at 100 ° C. Samples were taken at the 0 and 24 hours and then measured in them the content of the decomposition product using American HPH00 HPC. The chromatographic column was UMS-Rask ΟΌ8-Ά 3μ 4.6x150 mm, the mobile phase was 0.01 M KH ₂ PO ₄ : acetonitrile (94.5: 5.5), the flow rate was 1 ml / min, the detector wavelength was 254 nm, and the contents of all samples were calculated by the method of normalizing the area. The measurement results showed that the amount of decomposed product was less than 2% in an aqueous solution at 100 ° C. Thus, this compound was stable in an aqueous solution under destructive experimental conditions at high temperature.

Example 8. Determination of the solubility of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3 (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6- it is maleate monohydrate.

0.20 g of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H- is placed in a conical flask purin-6-one maleate monohydrate (purity> 99.5%). At 25 ° C., water was added dropwise with stirring until the solid had completely dissolved, a total of 14.2 ml of water was added. The solubility of the compound was calculated as 14.1 mg / ml, according to the volume of total added water.

Example 9. Determination of the structure of the single crystal [18- (1a, 3a, 4p)] - 2-amino-1,9-dihydro-9- [4hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purine-6- it is maleate monohydrate.

Single crystal growth: 0.20 g of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H is placed in a conical flask Purin-6-one maleate monohydrate (purity> 99.5%). Then, water is added dropwise with heating to dissolve the solid, followed by filtration. A little water was added to ensure that a solid did not form when the solution was cooled to room temperature. The conical flask is placed in a vacuum dryer with a window. A few days later, needle crystals formed and were measured with the help of X-gau 81pd1e Cg81a1 1) 1Gggas1ots1sg, Kdaki Kakh18 Kar1b 1P, MoK (0.71073A) monochromatic emitter, at a temperature of 293K.

Experimental data on the crystal structure of [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate monohydrates are presented as follows: __

Solvent Water The melting temperature Started to lose water at 65 ° С and melt at 156 ° С Crystalline form Colorless prism but 5.8947A B 25,097 A from 7.0881 A but 90.00 3 98.01 7 90.00 Us 1038,4 A ³ “ Space group P2 (1) Molecular formula С12Н1 ₅ Х5Оз-С4Н ₄ О ₄ -Н ₂ О Ζ 2 Orac.> Fuels and lubricants 1,408

Single crystal structure [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) 2-methylenecyclopentyl] -6H-purin-6-one maleate monohydrate .

Claims (5)

CLAIM 1. Monohydrate [18- (1a, 3a, 4c)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate. 2. A pharmaceutical composition having antiviral activity, comprising the compound of claim 1 and a pharmaceutically acceptable carrier. 3. The method of obtaining the compound according to claim 1, which includes the reaction of one equivalent or a slight excess of maleic acid as a source of anion M ^- with [18- (1a, 3a, 4p)] - 2-amino-1,9-dihydro-9- [ 4-hydroxy-3- (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one in methanol or water at room temperature to give [18- (1a, 3a, 4p)] - 2-amino-1.9 -dihydro-9- [4-hydroxy-3 (hydroxymethyl) -2-methylenecyclopentyl] -6H-purin-6-one maleate by crystallization followed by conversion of this compound to its hydrate. 4. A method of obtaining a pharmaceutical composition containing a compound according to claim 1 as an active component, which comprises mixing an effective amount of the active component with a pharmaceutically acceptable carrier. 5. The use of monohydrate [18- (1 a, 3a, 4p)] - 2-amino-1,9-dihydro-9- [4-hydroxy-3- (hydroxymethyl) 2-methylenecyclopentyl] -6H-purine-6- she is a maleate in the manufacture of a medicament for the treatment of hepatitis B virus infection and / or concomitant infection.