HK1071143B - Crystalline form of a ribofuranosyluronamide derivative; a human adenosine a2a receptor agonist - Google Patents

Description

Crystalline form of ribofuranosyluronamide derivative, human adenosine A2aReceptor agonists

The present invention relates to a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide, as well as to processes for its preparation, to compositions containing it and to its use.

6- [ (2, 2-Diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (also known as 6- [ (2, 2-diphenylethyl) amino ] -9- { (2R, 3R, 4S, 5S) -5- [ (ethylamino) carbonyl ] -3, 4- [ dihydroxytetrahydro-2-furanyl } -N {2- [ ({ [1- (2-pyridyl) -4-piperidyl ] amino } carbonyl) amino ] ethyl } -9H-purine-2-carboxamide) has the general formula (R: (2, 2-diphenylethyl) -4-piperidyl ] amino } carbonyl) ethyl } -9H-purine-2-carboxamide) shown below I) Structures, methods for their preparation are disclosed in International patent application PCT/IB01/00973, publication WO-A-01/94368.

6- [ (2, 2-Diphenylethyl) amino group as described in PCT/IB01/00973]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Ureido } ethyl) -9H-purine-2-amide is a human adenosine A_2aSelective functional agonists of receptors are used as anti-inflammatory agents in the treatment of diseases, in particular respiratory diseases. Therefore, can be used for treating any diseases related to adenosine A_2aReceptor agonist-related disorders. The compounds are useful in the treatment of diseases involving tissue damage caused by leukocytes (e.g., neutrophils, eosinophils, basophils, lymphocytes, macrophages). The compounds are useful as anti-inflammatory agents in the treatment of respiratory diseases such as Adult Respiratory Distress Syndrome (ARDS), bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, asthma, emphysema, bronchiectasis, chronic sinusitis and rhinitis. It is also useful in the treatment of: septic shock, male erectile dysfunction, male infertility, female infertility, hypertension, stroke, epilepsy, cerebral ischemia, peripheral vascular disease, ischemia reperfusion injury, diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, dermatitis, allergic dermatitis, eczema, ulcerative colitis, crohn's disease, inflammatory bowel disease, helicobacter pylori (Heliobacter pylori) gastritis, non-helicobacter pylori (non-Heliobacter pylori) gastritis, gastrointestinal damage caused by non-steroidal anti-inflammatory drugs or psychiatric disease or wound healing.

Examples 8 and 35 of PCT/IB01/00973 both describe the preparation of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide. These methods provide a solid, amorphous form of the compound (see comparative examples 1 and 2 below).

Before a pharmaceutical compound can be commercialized, a mass production process that can reliably provide the compound in consistent and high purity must be developed. In addition, the method must provide a suitable formulation of the compound so that the compound can be provided to the patient in a convenient dosage form and be chemically and physically stable for a long period of time.

Crystalline forms of a pharmaceutical compound have various advantages over amorphous forms of the compound. For example, the compound can be easily purified by crystallization and recrystallization. Crystallization is a cheaper and more convenient method for large scale purification than other known purification methods such as chromatography. In addition, crystalline forms are generally more stable than amorphous forms before, during, and during subsequent storage. In addition, when formulated into a medicament for administration by inhalation, it is generally more readily milled or micronized to an inhalable size (generally considered to be a particle diameter less than 5 microns) than the amorphous form.

There is no generally applicable method of preparing crystalline forms of amorphous materials. In fact, it is not possible to know from the outset whether any crystalline form of a given compound exists. When a compound is shown to be crystallizable, extensive experimentation is usually required to determine which method can isolate the crystalline form. The correct combination of several independently variable conditions (e.g., solvent concentration, solvent composition, temperature, cooling rate) must be determined empirically through trial and error and success cannot be guaranteed.

Many attempts to crystallize 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide have failed. The compounds were slurried in various solvents (e.g., methanol, ethanol, tetrahydrofuran, acetonitrile, dichloromethane, toluene) with or without water at room temperature, but none had the results. Likewise, heating the slurry to obtain a solution which is cooled in a conventional manner does not result in a satisfactory crystalline form.

It has now surprisingly been found that 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide exists in crystalline form and can be prepared by the process described below.

The present invention therefore provides a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide.

The present invention also provides a process for the preparation of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide comprising the steps of:

(a) dissolving amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide in an organic solvent containing at least 2% W/W dissolved water, and

(b) the solution is heated to a temperature of at least 50 ℃ until crystallization occurs.

The method is particular in several respects. The solvent system developed (at least 2% w/w water in organic solvent) is unconventional. Further, crystallization is started by raising the temperature of a solution of the amorphous compound in the solvent, whereas in the conventional crystallization method, crystallization is performed by cooling the solution. Thus, the presented process provides a unique and unconventional combination of conditions that unexpectedly solves the crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-amide.

The crystalline form provided by the above described process has additional unexpected advantages over the amorphous form in solutions of the same concentration: it has a higher resistivity. This is particularly useful in the preparation of formulations for nebulisers operating by the principle of electro-hydraulic dynamics (see below), since the resistivity of the formulation can be reduced by adding, for example, sodium chloride, but it is not possible to increase it at present. Thus, the higher the resistivity of a compound formulated in solution, the greater the tunability in the final resistivity of the formulation.

Any solvent capable of simultaneously dissolving amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-amide and at least 2% w/w water may be used in the process of the present invention. Examples of suitable solvents include: 2-butanone, ethyl acetate, acetonitrile, isopropyl acetate, isopropanol, methyl acetate, butan-2-ol, and methyl acetate. Preferred organic solvents are 2-butanone, methyl acetate and ethyl acetate. Methyl acetate and ethyl acetate are particularly preferred.

The water content of the organic solvent can be conveniently measured using the Karl-Fischer method.

The temperature must be at least 50 c in order to initiate crystallization at a practical rate. Preferably, temperatures of 50 ℃ to 80 ℃ are used.

Crystallization is generally complete in 24 to 72 hours, but longer or shorter times are also possible, depending on the choice of organic solvent and temperature.

The crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (hereinafter "the compound of the invention") may be administered alone, but is typically administered in admixture with a suitable pharmaceutical excipient, diluent or carrier selected with regard to the intended route of administration and standard pharmaceutical practice.

For example, it may be administered orally, buccally or sublingually in the form of tablets, capsules, multiparticulates, gels, films, ovules, elixirs, solutions or suspensions, which may contain flavouring or colouring agents, for immediate, delayed, modified, sustained release, pulsed or controlled release. It may also be administered in a fast dispersing or fast dissolving dosage form, or as a high energy dispersion, or as coated particles. The formulations may be coated or uncoated as desired.

The solid pharmaceutical compositions, e.g. tablets, may comprise excipients such as microcrystalline cellulose, lactose, sodium citrate, calcium carbonate, dibasic calcium phosphate, glycine and starch (preferably corn, potato or tapioca starch), disintegrants such as sodium starch glycolate, croscarmellose sodium and certain complex silicates, and granulation binders such as polyvinylpyrrolidone, Hydroxypropylmethylcellulose (HPMC), Hydroxypropylcellulose (HPC), sucrose, gelatin and acacia. Additionally, lubricating agents such as magnesium stearate, sodium stearyl fumarate, sodium lauryl sulfate, stearic acid, glyceryl behenate, and talc may be included.

General examples

Tablet formulations may typically contain from 0.01 mg to 500 mg of active compound, whilst tablet fill weights may range from 50 mg to 1000 mg. An example of a 10mg tablet formulation is shown below:

composition (I) ％w/w

Compound 10.000 of the invention^*

Lactose 64.125

Starch 21.375

Croscarmellose sodium 3.000

Magnesium stearate 1.500

^*The dosage is adjusted according to the activity of the medicine.

The tablets may be prepared by standard methods, for example direct compression or wet or dry granulation. The tablet core may be coated with a suitable coating.

Solid compositions of a similar type may also be used as fillers in gel or HPMC capsules. Preferred excipients in this regard include lactose, starch, cellulose, milk sugar or high molecular weight polyethylene glycols. In preparing aqueous suspensions and/or elixirs, the compounds of the invention may be combined with various sweetening or flavouring agents, colouring matter or dyes, with emulsifying and/or suspending agents and with diluents such as water, ethanol, propylene glycol or glycerin, and combinations thereof.

The compounds of the invention may also be administered parenterally, for example intravenously, intraarterially, intraperitoneally, intrathecally, intraventricularly, intraureterally, intrasternally, intracranially, intramuscularly or subcutaneously, or may be administered by infusion or needleless injection techniques. For such parenteral administration, it is preferred to use a sterile aqueous solution which contains other substances, such as co-solvents and/or sufficient salt or glucose to render the solution isotonic with blood. The aqueous solution should be suitably buffered if necessary (preferably at a pH of 3 to 9). Preparation of suitable parenteral formulations under sterile conditions can be readily accomplished by standard pharmaceutical techniques well known to those skilled in the art.

For oral and parenteral administration to human patients, the daily dosage level of the compounds of the invention is generally from 0.00001 to 100mg/kg, preferably from 0.0001 to 100mg/kg (single or divided doses).

Thus, tablets or capsules of the compounds of the invention may contain from 0.01 to 500 mg of active substance for one or two or more administrations, as appropriate. In any event, the physician will determine the actual dosage which will be most suitable for any individual patient, and this will vary with the age, weight and response of the particular patient. The above-described doses are examples of common situations. Higher or lower dosage ranges are, of course, intended for certain individual cases and are also within the scope of the invention.

The compounds of the invention may also be administered intranasally or by inhalation, and are conveniently administered in dry powder form (alone or as a mixture, e.g. a lactose-containing mixture) from a dry powder inhaler, or as a spray aerosol from a pressurised container, pump, nebulizer, atomiser (preferably an electro-hydraulic powered nebulizer producing fine droplets) or spray device, with or without the use of a suitable propellant, examples of which are: dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, hydrofluorocarbons such as 1, 1, 1, 2-tetrafluoroethane (HFA 134A [ trade mark ]) or 1, 1, 1, 2, 3, 3, 3-heptafluoropropane (HFA 227EA [ trade mark ]), carbon dioxide, and perfluoro-substituted hydrocarbons such as perfluororon (Perflukron, trade mark) or other suitable gases. In the case of a pressurized aerosol, dosing can be achieved by defining a dosage unit through a valve. The pressurised container, pump, spray, atomiser or spray device may comprise a solution or suspension of the active compound, for example using ethanol (optionally aqueous ethanol) or a mixture of an agent suitable for dispersion, dissolution and expansion release (extending release) and a propellant as the solvent, which may further comprise a lubricant, for example sorbitan trioleate (sorbitantrioleate). Capsules for use in an inhaler or insufflator (insufflator) may be prepared, foamers and cartridges (prepared from, for example, gelatin or HPMC) containing a powder mix of a compound of the invention, a suitable powder base such as lactose or starch, and a performance modifier such as 1-leucine, mannitol or magnesium stearate.

Prior to inhalation of the compounds of the invention in a dry powder or suspension formulation, they are micronised to a size suitable for administration by inhalation (typically considered to be less than 5 microns). Micronization can be carried out by various methods, such as spiral jet milling, fluidized bed jet milling, or crystallization using supercritical fluids.

In a suitable solution formulation for use in an electro-hydraulic powered nebulizer for producing fine droplets, each stroke contains from 1 μ g to 10mg of a compound of the invention and the stroke volume varies from 1 to 100 μ l. A typical formulation may comprise a compound of the invention, propylene glycol, sterile water, ethanol and sodium chloride. Instead of propylene glycol, other solvents such as glycerol or polyethylene glycol may be used. Specific examples of formulations for use in an electro-hydraulic powered nebulizer are as follows:

composition (I) Dosage of

Compound of the invention 14.6mg

Propylene glycol 0.08mL

Sterile water 0.02mL

Ethanol to 1mL

Sodium chloride adjusts resistivity to 1100 ohm-m as required

Preferably, the aerosol or dry powder formulation used is controlled so that it contains from 1 to 4000 μ g of a compound of the invention per metered dose or "puff" administered to the patient. Aerosols, which range in total from 1 μ g to 20 mg per day, may be administered in a single dose, or more commonly, in divided doses throughout the day.

Alternatively, the compounds of the invention may be administered in the form of suppositories or pessaries, or may be administered topically in the form of lotions, solutions, emulsions, creams or dusting powders. The compounds of the present invention may also be administered through the skin or through the skin, for example, by using a skin patch. It may also be administered by pulmonary, vaginal or rectal means.

For topical application to the skin, the compounds of the invention may be formulated in a suitable ointment containing the active substance suspended or dissolved, for example, in a mixture of one or more of the following: mineral oil, liquid paraffin, white vaseline, propylene glycol, polyoxyethylene polyoxypropylene compound, emulsifying wax and water. Alternatively, it may be formulated as a suitable lotion or emulsion, suspended or dissolved in, for example, a mixture of one or more of the following: mineral oil, sorbitan monostearate, polyethylene glycol, liquid paraffin, polysorbate 60, cetyl esters wax, cetearyl alcohol, 2-octyldodecanol, benzyl alcohol and water.

The compounds of the invention may also be combined with cyclodextrins. Cyclodextrins are known to form entrapped and non-entrapped complexes with drug molecules. The form of the drug-cyclodextrin complex can modulate the solubility, dissolution rate, bioavailability, and/or stability of the drug molecule. Drug-cyclodextrin complexes are generally used in most dosage forms and routes of administration. In addition to direct complexation with the drug, cyclodextrins may also be used as auxiliary additives, e.g. as carriers, diluents or solubilisers. alphA-, betA-and gammA-cyclodextrins are most commonly used, and suitable examples are described in WO-A-91/11172, WO-A-94/02518 and WO-A-98/55148.

It is to be understood that reference herein to treatment includes curative, palliative and prophylactic treatment.

The crystalline forms of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide provided by the present invention may optionally be combined with other pharmacologically active compounds. Preferred combinations for use in airway obstruction and other inflammatory diseases include (a) a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide and (b) a corticosteroid, an adrenergic β 2 agonist or an anticholinergic compound. Examples of preferred adrenergic beta 2 agonists are salmeterol (salmeterol) and formoterol (formoterol). Preferred anticholinergic compounds are tiotropium bromide (tiotropium), ipratropium bromide (ipratropium) and oxitropium bromide (oxitropium) salts.

The present invention therefore provides:

(i) a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide;

(ii) a process for the preparation of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide;

(iii) a pharmaceutical composition comprising a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-amide, in association with a pharmaceutically acceptable excipient, diluent or carrier;

(iv) a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-amide for use as a medicament;

(v) one kind is used as having A_2a6- [ (2, 2-diphenylethyl) amino groups of agents with receptor agonist activity]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]A crystalline form of ureido } ethyl) -9H-purine-2-amide;

(vi) a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-amide for use as an anti-inflammatory agent;

(vii) a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-amide for use as a medicament for the treatment of a respiratory disease;

(viii) (viii) the crystalline form as in (vii), wherein the disease is selected from Adult Respiratory Distress Syndrome (ARDS), bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, asthma, emphysema, bronchiectasis, chronic sinusitis and rhinitis;

(ix) a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide for use as a medicament in the treatment of: septic shock, male erectile dysfunction, male infertility, female infertility, hypertension, stroke, epilepsy, cerebral ischemia, peripheral vascular disease, post-ischemic reperfusion injury, diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, dermatitis, allergic dermatitis, eczema, ulcerative colitis, crohn's disease, inflammatory bowel disease, heliobacter pylori gastritis, non-steroidal anti-inflammatory drug-induced gastrointestinal damage or psychiatric disease, or wound healing;

(x)6- [ (2, 2-Diphenylethyl) amino group]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Crystalline forms of ureido } ethyl) -9H-purine-2-carboxamide having formula A_2aUse in medicine of receptor agonist activity;

(xi) Use of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide in the manufacture of an anti-inflammatory agent;

(xii) Use of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide in the manufacture of a medicament for the treatment of a respiratory disease;

(xiii) The use as described in (xii), wherein the disease is selected from Adult Respiratory Distress Syndrome (ARDS), bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, asthma, emphysema, bronchiectasis, chronic sinusitis and rhinitis;

(xiv) Use of a crystalline compound of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide in the manufacture of a medicament for the treatment of: septic shock, male erectile dysfunction, male infertility, female infertility, hypertension, stroke, epilepsy, cerebral ischemia, peripheral vascular disease, post-ischemic reperfusion injury, diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, dermatitis, allergic dermatitis, eczema, ulcerative colitis, crohn's disease, inflammatory bowel disease, heliobacter pylori gastritis, non-steroidal anti-inflammatory drug-induced gastrointestinal damage or psychiatric disease, or wound healing;

(xv) Use of A_2aA method of treating mammals, including humans, with a receptor agonist comprising administering an effective amount of 6- [ (2, 2-diphenylethyl) amino]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]A crystalline form of ureido } ethyl) -9H-purine-2-amide for treating said mammal;

(xvi) A method of treating an inflammatory disease in a mammal, including a human, comprising treating said mammal with an effective amount of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide;

(xvii) A method of treating a respiratory disorder in a mammal, including a human, comprising treating said mammal with an effective amount of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide;

(xviii) A method as in (xvii), wherein the disease is selected from Adult Respiratory Distress Syndrome (ARDS), bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, asthma, emphysema, bronchiectasis, chronic sinusitis, and rhinitis; and

(xix) A method of treating the following diseases in mammals, including humans: septic shock, male erectile dysfunction, male infertility, female infertility, hypertension, stroke, epilepsy, cerebral ischemia, peripheral vascular disease, post-ischemic reperfusion injury, diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, dermatitis, allergic dermatitis, eczema, ulcerative colitis, Crohns disease, inflammatory bowel disease, Heliobacter pylori gastritis, non-steroidal anti-inflammatory drug-induced gastrointestinal damage or psychiatric disease, or wound healing comprising treating with an effective amount of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-amide The mammal.

The following examples serve to illustrate the invention.

Example 1

Amorphous 6- [ (2, 2-diphenylethyl) amino group]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Ureido } ethyl) -9H-purine-2-amide (5.0g, 0.0064 mol) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar, thermometer and condenser. A solution of 2% v/v water in 2-butanone (50ml) was then added and the resulting mixture was heated to 69-71 deg.C with stirring under a nitrogen atmosphere to give a preliminary clear transparent solution. After 24 hours at this temperature, a fluid white suspension had formed. The temperature of the mixture was then reduced to 59-61 ℃ and stirring was continued for 24 hours. The mixture was then cooled to room temperature over 30 minutes and stirred at that temperature for 1 hour. The solid was collected by filtration and the filter cake was rinsed with 2-butanone (50 mL). The solid was then dried under reduced pressure at a temperature of 50 ℃ for 48 hours until the title compound (3.99g) was obtained as colorless crystals,¹H-NMR measurement showed that it contained about 1% by weight of 2-butanone. Before further characterization data were obtained, the material obtained was dried under reduced pressure at a temperature of 50 ℃ for a further 5 days to give 6- [ (2, 2-diphenylethyl) amino ] containing approximately 0.5% by weight of 2-butanone]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Ureido } ethyl) -9H-purine-2-amide. The water content of the material is detected to show that the material also contains 1.6 weight portionsAmount% water. Increasing the temperature further dries, further reducing the level of 2-butanone present, indicating that the residual 2-butanone may not be an intrinsic part of the crystal lattice, but instead is trapped in the channels of the crystal lattice.

The crystalline form prepared by the above process has the following characteristics:

low resolution mass spectrometry

Positive atmospheric pressure chemical ionization: m/Z [ MH⁺]778。

Proton nuclear magnetic resonance

(300MHz，d₆-DMSO, 30 ℃) δ: 8.80(0.8H, brt), 8.67(0.2H, brs), 8.53(0.2H, brs), 8.48(0.8H, s), 8.28(1H, brt), 8.10-8.02(1.8H, m), 7.84(0.2H, brs), 7.50-7.30(5H, m), 7.26(4H, t), 7.14(2H, t), 6.75(1H, d), 6.56(1H, dd), 6.11-5.82(3H, m), 5.65(1H, m), 5.60-5.45(1H, m), 4.80-4.50((2.4H, m), 4.40-3.95(5.6H, m), 3.67-3.55(1H, m), 3.40-3.10(6H, m)), 3.67-3.35H, 3.83 (3H, t), 2.2H, m), 3.2H-3.2H, m), 3.2H, 3665 (3.0.2H, m), 3.3.3H, 3.2H, m), 3.3.6, 7H, 7-7H, 7.6, 7H, 7.6, 7, 7.6, 5H.

Obtained at 70 deg.C¹The H-NMR spectrum results in the disappearance of the signal peak because more than one conformational isomer is observed at 30 ℃.

Infrared spectroscopy

Infrared spectroscopy was performed using a Nicolet 360 Avatar FT-IR spectrometer equipped with a d-TGS detector and a single reflection diamond ATR accessory (Golden Gate, trade Mark). The sample was prepared by placing approximately 0.5mg of sample on the diamond ATR crystal and applying pressure through an anvil and embedded pressure control mechanism to ensure good crystalline sample contact. At 4cm^-1Spectra were recorded at resolution using 32 background and 32 sample scans with Happ Genzel apodization function.

Major peaks 3478, 33 recorded95, 3375, 3301, 3060, 3024, 2971, 2943, 1657, 1639, 1597, 1552, 1527, 1494, 1475, 1468, 1456, 1434, 1405, 1374, 1351, 1324, 1310, 1300, 1233, 1220, 1163, 1150, 1123, 1113, 1102, 1078, 1054, 1000, 976, 947, 932, 909, 864, 813, 777, 759, 734, 699, 683, and 667cm^-1。

X-ray diffraction (PXRD)

The powder X-ray diffraction pattern was measured using a SIEMENS D5000 powder X-ray diffractometer equipped with an automatic sample changer, a theta-theta goniometer, an automatic beam diverging slit, a secondary monochromator and a scintillation counter. Samples for analysis were prepared by filling the powder onto a silicon wafer sample holder. Rotation of the sample while using copper K-alpha₁X-ray (wavelength: 1.5406 a) the sample was irradiated by operating an X-ray tube under 40kV/40mA conditions. The analysis was performed using a step-and-scan type goniometer, set under the condition that 5 seconds were counted at intervals of 0.020 ° at 2 θ angles ranging from 4 ° to 45 °.

The resulting diffraction pattern is shown in FIG. 1.

The peaks with peak intensities greater than 5% are shown in table 1. In Table 1, the "2-theta angle" is related to the interplanar spacing of the crystal, and the intensity is expressed as a percentage of the maximum peak value (I/I)₁)。

TABLE 1

2 theta angle °	Strength%	2 theta angle °	Strength%	2 theta angle °	Strength%	2 theta angle °	Strength%
								5.185	22.9	17.099	27.4	24.861	29.5	33.177	13.8
6.647	96.0	17.369	23.8	24.966	29.5	33.596	18.3
								8.232	23.7	17.908	35.6	25.795	26.9	34.484	18.2
9.131	11.3	18.517	35.8	26.214	24.4	35.048	16.2
								9.794	15.4	18.753	29.0	26.570	21.4	35.399	13.7
10.702	10.1	19.414	62.3	26.949	40.8	35.704	14.2
								11.370	16.1	20.079	35.3	27.054	38.5	36.797	17.1
12.495	6.3	20.418	100	27.308	28.3	37.819	15.4
								13.494	30.1	21.357	38.0	27.776	21.2	38.667	16.6
14.393	7.8	21.696	77.7	28.718	25.1	39.568	12.8
								14.536	6.8	22.455	28.3	28.991	24.4	40.463	12.9
14.899	8.1	23.187	65.2	29.854	43.7	40.929	17.6
								15.148	10.1	23.697	27.0	30.581	16.7	41.473	16.2
15.369	9.9	24.030	15.0	31.142	15.6	42.455	14.5
								16.111	33.5	24.755	28.5	32.517	17.2	43.347	14.5
16.439	30.2

The skilled crystallographist will appreciate that the relative intensities of the peaks in table 1 may vary due to a number of factors, such as the directional effect of the crystals in the X-ray beam, or the purity of the material being analyzed, or the crystallinity of the sample. Sample height variations may also cause the peak position to shift, but its peak position remains substantially at the peak position as defined in table 1.

The skilled crystallographist will also understand that using different wavelengths will result in different shifts according to the bragg equation-n λ ═ 2d sin θ.

Such further PXRD patterns generated by utilizing different wavelengths are considered additional representations of the PXRD patterns of the crystals of the present invention and are also included within the scope of the present invention.

Differential Scanning Calorimetry (DSC)

Differential scanning calorimetry was performed using a Perkin Elmer DSC-7 instrument equipped with an automatic sample changer. Approximately 3mg of sample was accurately weighed, placed in a 50 microliter aluminum dish, and sealed with a perforated lid flange. While blowing nitrogen gas, the sample was heated at 20 ℃/min in a temperature range of 40 ℃ to 250 ℃.

The results are shown in FIG. 2. The melting range is approximately 185-195 ℃.

Thermogravimetric analysis (TGA)

Thermogravimetric analysis was performed using a Perkin Elmer pyrral TGA instrument equipped with an automatic sample changer. Approximately 8mg of sample was accurately weighed and placed in a ceramic dish. While blowing nitrogen gas, the sample was heated at 20 ℃/min in a temperature range of 20 ℃ to 350 ℃.

The results are shown in FIG. 3.

Example 2

To amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (66.1g, 0.085 mol) was added a 2% v/v water solution in 2-butanone (660mL) and the resulting mixture was heated at 69-71 ℃ for 18 hours. Thereafter, crystals of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (0.149g) were seeded to the mixture and stirring was continued at 69-71 ℃ for 8 hours. The temperature of the mixture was then reduced to 59-61 ℃ and stirring was continued at this temperature for 64 hours. The resulting slurry was then cooled to room temperature and the solids collected by filtration. The filter cake was washed with 2-butanone (2X 100mL), and the resulting solid was dried at 60 ℃ under vacuum for 60 hours and then at 80 ℃ under vacuum for 72 hours to give a crystalline solid (35.72g) containing a trace of 2-butanone. The analytical data collected for this product, including characterization by powder X-ray diffraction, were consistent with the data described in example 1.

Example 3

Ethyl acetate (25mL) was shaken with deionized water (10mL) at room temperature and the organic phase was collected to give a solution of ethyl acetate saturated with water. Amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (1.0g, 0.0013 moles) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar and condenser. To the amorphous solid was then added a water-saturated ethyl acetate solution (10mL) prepared as above, and the resulting mixture was heated to 55-60 ℃ under a nitrogen atmosphere. Crystalline 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (about 0.005g) was added as seed crystals, and the resulting mixture was stirred at 55-60 ℃ for 3 days to form a slurry. The mixture was then cooled to room temperature and the solid was collected by filtration. The filter cake was then washed with ethyl acetate (2X 5mL) and the resulting solid was then dried at 50 ℃ for 24 hours to give a crystalline solid (0.898g) containing traces of sodium chloride (inadvertently present in the starting material and subsequently filtered off with the product) and ethyl acetate. The analytical data collected for this product, including characterization by powder X-ray diffraction, are consistent with the data described in example 1, except for the presence of trace amounts of sodium chloride.

Example 4

A2% v/v solution of water in acetonitrile was prepared by dissolving deionized water (2.0mL) in acetonitrile and then adding acetonitrile to bring the volume to 100 mL. Amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (1.0g, 0.0013 moles) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar and condenser. To the amorphous solid was then added a 2% v/v solution of water in acetonitrile (10mL) prepared as above and the resulting mixture was heated to 55-60 ℃ under a nitrogen atmosphere. Crystalline 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (approximately 0.005g) was added as seed crystals, and the resulting mixture was stirred at 55-60 ℃ for 3 days to form a thick slurry. The mixture was then cooled to room temperature and acetonitrile (10mL) was added. The solid was then collected by filtration and the filter cake was washed with acetonitrile (2X 5mL) and then dried at 50 ℃ for 24 hours to give a crystalline solid (0.866g) containing traces of sodium chloride (inadvertently present in the starting material and subsequently filtered off with the product) and acetonitrile. The analytical data collected for this product, including characterization by powder X-ray diffraction, are consistent with the data described in example 1, except for the presence of trace amounts of sodium chloride.

Example 5

Isopropyl acetate (25mL) was shaken with deionized water (10mL) at room temperature and the organic phase was collected to give a water saturated isopropyl acetate solution. Amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (1.0g, 0.0013 moles) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar and condenser. To this amorphous solid was then added the water saturated isopropyl acetate solution prepared as above and the resulting mixture was heated to 55-60 ℃ under a nitrogen atmosphere. Crystalline 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (about 0.005g) was added as seed crystals, and the resulting mixture was stirred at 55-60 ℃ for 3 days to form a slurry. The mixture was then cooled to room temperature and the solid collected by filtration and the filter cake washed with isopropyl acetate (2 x 5mL) and then dried at 50 ℃ for 24 hours to give a colourless, crystalline solid (0.445g) containing traces of sodium chloride (inadvertently present in the starting material and subsequently filtered off together with the product) and isopropyl acetate. The analytical data collected for this product, including characterization by powder X-ray diffraction, are consistent with the data described in example 1, except for the presence of trace amounts of sodium chloride.

Example 6

A2% v/v solution of water in isopropanol was prepared by dissolving deionized water (2.0ml) in isopropanol and then adding isopropanol to bring the volume to 100 ml. Amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (1.0g, 0.0013 moles) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar and condenser. To this amorphous solid was then added a 2% v/v solution of water in isopropanol prepared above and the resulting mixture was heated to 55-60 ℃ under a nitrogen atmosphere. Crystalline 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (about 0.005g) was added as seed crystals, and the resulting mixture was stirred at 55-60 ℃ for 8 days to form a slurry. The mixture was then cooled to room temperature and the solid collected by filtration and the filter cake washed with isopropanol (2X 5ml) and then dried at 50 ℃ for 24 hours to give a colourless, crystalline solid (0.866g) containing traces of sodium chloride (inadvertently present in the starting material and filtered off with the product) and isopropanol. The analytical data collected for this product, including characterization by powder X-ray diffraction, are consistent with the data described in example 1, except for the presence of trace amounts of sodium chloride.

Example 7

Amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (1.0g, 0.0013 moles) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar and condenser. To the amorphous solid was then added a methyl acetate solution (10mL) and deionized water (0.20mL), and the resulting mixture was heated to 55-60 ℃ under a nitrogen atmosphere. Crystalline 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (approximately 0.005g) was added as seed crystals, and the resulting mixture was stirred at 55-60 ℃ for 24 hours to form a slurry. The mixture was then cooled to room temperature and the solid was collected by filtration. The solid was then collected by filtration and the filter cake was washed with methyl acetate (2X 5mL) and then dried at 50 ℃ for 24 hours to give a crystalline solid (0.860g) containing traces of sodium chloride (inadvertently present in the starting material and filtered off with the product) and methyl acetate. The analytical data collected for this product, including characterization by powder X-ray diffraction, are consistent with the data described in example 1, except for the presence of trace amounts of sodium chloride.

Example 8

Amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (1.0g, 0.0013 moles) was added to a vessel equipped with a Teflon ® (trade Mark) sealed magnetic stir bar and condenser. Butan-2-ol (10mL) and deionized water (0.20mL) were then added to the amorphous solid and the resulting mixture was heated to 55-60 ℃ under a nitrogen atmosphere. Crystalline 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. beta. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide (approximately 0.005g) was added as seed crystals and the resulting mixture was stirred at 55-60 ℃ for about 3 weeks, during which time a slurry was slowly formed. The mixture was then cooled to room temperature and the solid was collected by filtration. The solid was then collected by filtration and the filter cake was washed with butan-2-ol (2X 5ml) and then dried at 50 ℃ for several days to give a crystalline solid (0.860g) containing traces of sodium chloride which were inadvertently present in the starting material and filtered off with the product. The analytical data collected for this product, including characterization by powder X-ray diffraction, are consistent with the data described in example 1, except for the presence of trace amounts of sodium chloride.

Example 9

Methanesulfonic acid (17.5mL, 0.269 mol) was added to A suspension of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl-. betA. -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide (200g, 0.245 mol) (see WO-A-01/94368) in deionized water (1000mL) under A nitrogen atmosphere with stirring. The resulting mixture was then heated up to 95 ℃ and stirred in this temperature range for approximately 5 hours, during which time all the starting material was consumed. The reaction was then stopped by the addition of 10% w/w aqueous sodium phosphate dibasic heptahydrate (82mL), and the resulting solution was cooled to room temperature, followed by the addition of methyl acetate (2000 mL). Then, while stirring vigorously, 10% w/w aqueous sodium dihydrogen phosphate heptahydrate solution (1300mL) was slowly added to the resulting mixture. The phases were then separated and the organic phase was washed with 2% w/w aqueous sodium phosphate dibasic heptahydrate (2000 mL). After phase separation, the organic layer was collected and methyl acetate (1000ml) was added. The resulting mixture was then azeotropically dried by distillation at atmospheric pressure until the amount of water remaining in the mixture was approximately 2% w/w as indicated by Karl-Fischer analysis. Where more methyl acetate (3000mL, added in portions during the distillation) was added and about 3000mL of fractions were collected in total. The mixture was heated at reflux for 18 hours with a water content of 1.8% w/w. Deionized water (4mL) was then added to adjust the water content of the mixture to 2.0% w/w and refluxing was continued for 24 hours before a slurry was formed. The mixture was then cooled to room temperature and the solid was collected by filtration. The filter cake was washed with a 2% w/w solution of water in methyl acetate (200mL then 400mL) and dried at 50 ℃ under reduced pressure for 20 hours to give a crystalline material (155.6g) contaminated with trace amounts of inorganic salts. This material (153.6g) was suspended in a mixture of ethyl acetate (1070ml) and ethanol (460ml) and heated to reflux for 10 minutes to give a slightly turbid solution. After cooling to room temperature, the mixture was filtered to give a clear filtrate, which was then distilled at atmospheric pressure. During the distillation, ethyl acetate (2900mL) was added in additional portions, and a total of 2900mL fractions were collected. Near the end of the distillation it was necessary to add deionized water (60mL, added in two portions) to keep the product in solution and to create the necessary conditions for crystals to appear. At the end of the distillation, approximately 2 mole% ethanol, and approximately 2.3% w/w water remained in the mixture. For convenience, the mixture was held at this point for 60 hours at room temperature. The mixture was then heated at about 60 ℃ for 30 hours, during which time a slurry was formed. The mixture was then cooled to room temperature and the solid was collected by filtration. The filter cake was then washed with a 2% v/v solution of water in ethyl acetate (150mL then 300mL) and dried under vacuum at 70 ℃ to give a colorless crystalline solid (134g) containing traces of residual ethyl acetate. The analytical data collected for this product, including characterization by powder X-ray diffraction, were consistent with the data described in example 1.

Comparative example 1

For 6- [ (2, 2-Diphenylethyl) amino prepared by the method of example 8 of WO-A-01/94368]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Ureido } ethyl) -9H-purine-2-carboxamide a sample was subjected to powder X-ray diffraction analysis and was found to be amorphous. The respective X-ray diffraction patterns are shown in fig. 4. The powder X-ray diffraction pattern was measured by using a SIEMENS D5000 powder X-ray diffractometer equipped with an automatic sample changer, an theta-theta goniometer, an automatic beam diverging slit, a secondary monochromator and a scintillation counter. Samples for analysis were prepared by filling the powder onto a silicon wafer sample holder. While rotating the sample, copper K-alpha was used₁X-ray (wavelength: 1.5406 a) the sample was irradiated by operating an X-ray tube under 40kV/40mA conditions. The analysis was performed using a goniometer operated in a segmented scanning mode, with the conditions set to count 5 seconds at intervals of 0.020 ° for 2 θ angles in the range of 4 ° to 45 °.

Comparative example 2

For 6- [ (2, 2-Diphenylethyl) amino group prepared by the method of example 35 of WO-A-01/94368]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Ureido } ethyl) -9H-purine-2-carboxamide a sample was subjected to powder X-ray diffraction analysis and was found to be amorphous. The respective X-ray diffraction patterns are shown in fig. 5. The powder X-ray diffraction pattern was obtained by using a sample changer equipped with an automatic sample changer, a theta-theta goniometer, an automatic beam diverging slit,two-stage monochromator and scintillation counter SIEMENS D5000 powder X-ray diffractometer. Samples for analysis were prepared by filling the powder onto a silicon wafer sample holder. While rotating the sample, copper K-alpha was used₁X-ray (wavelength: 1.5406 a) the sample was irradiated by operating an X-ray tube under 40kV/40mA conditions. The analysis was performed using a goniometer operated in a segmented scanning mode, with the conditions set to count 5 seconds at intervals of 0.020 ° for 2 θ angles in the range of 4 ° to 45 °.

Claims (13)

1.6- [ (2, 2-Diphenylethyl) amino group]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]A crystalline form of ureido } ethyl) -9H-purine-2-amide characterized by a solid infrared spectrum having significant absorptions as follows: v is 3478, 3395, 3375, 3301, 3060, 3024, 2971, 2943, 1657, 1639, 1597, 1552, 1527, 1494, 1475, 1468, 1456, 1434, 1405, 1374, 1351, 1324, 1310, 1300, 1233, 1220, 1163, 1150, 1123, 1113, 1102, 1078, 1054, 1000, 976, 947, 932, 909, 864, 813, 777, 759, 734, 699, 683 and 667cm^-1And copper K-alpha at a wavelength of 1.5406 angstroms₁X-ray obtained powder X-ray diffraction pattern showing the following main peaks: 5.185, 6.647, 8.232, 9.131, 9.794, 10.702, 11.370, 12.495, 13.494, 14.393, 14.536, 14.899, 15.148, 15.369, 16.111, 16.439, 17.099, 17.369, 17.908, 18.517, 18.753, 19.414, 20.079, 20.418, 21.357, 21.696, 22.455, 23.187, 23.697, 24.030, 24.755, 24.861, 24.966, 25.795, 26.214, 26.570, 26.949, 27.054, 27.308, 27.776, 28.718, 28.991, 29.854, 30.581, 31.142, 32.517, 33.177, 33.596, 34.484, 35.048, 35.399, 35.704, 36.797, 37.819, 38.667, 39.568, 40.463, 40.929, 41.473, 42.455 and 43.347 degrees 2 θ.

2. A pharmaceutical composition comprising a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide as defined in claim 1, together with a pharmaceutically acceptable excipient, diluent or carrier.

3. 6- [ (2, 2-diphenylethyl) amino group as defined in claim 1]-9- (N-ethyl-beta-D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl]Crystalline forms of ureido } ethyl) -9H-purine-2-carboxamide having formula A_2aUse in medicine of receptor agonist activity.

4. Use of a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide as defined in claim 1 for the manufacture of an anti-inflammatory medicament.

5. Use of the crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide as defined in claim 1 for the manufacture of a medicament for the treatment of respiratory diseases.

6. The use according to claim 5, wherein the disease is selected from adult respiratory distress syndrome, bronchitis, chronic obstructive pulmonary disease, cystic fibrosis, asthma, emphysema, bronchiectasis, chronic sinusitis and rhinitis.

7. Use of the crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidinyl ] ureido } ethyl) -9H-purine-2-carboxamide as defined in claim 1 in the manufacture of a medicament for the treatment of: septic shock, male erectile dysfunction, male infertility, female infertility, hypertension, stroke, epilepsy, cerebral ischemia, peripheral vascular disease, post-ischemic reperfusion injury, diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, dermatitis, allergic dermatitis, eczema, ulcerative colitis, crohn's disease, inflammatory bowel disease, heliobacter pylori gastritis, non-steroidal anti-inflammatory drug-induced gastrointestinal damage or psychiatric disease, or wound healing.

8. A process for preparing a crystalline form of 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide as defined in claim 1, comprising the steps of:

(a) dissolving amorphous 6- [ (2, 2-diphenylethyl) amino ] -9- (N-ethyl- β -D-ribofuranosyluronamide) -N- (2- { N' - [1- (2-pyridyl) -4-piperidyl ] ureido } ethyl) -9H-purine-2-carboxamide in an organic solvent containing at least 2% w/w dissolved water; and is

(b) The resulting solution is heated to at least 50 ℃ until crystals appear.

9. The process according to claim 8, wherein the organic solvent is 2-butanone, ethyl acetate, acetonitrile, isopropyl acetate, isopropanol, methyl acetate, butan-2-ol or methyl acetate.

10. The process according to claim 8, wherein the organic solvent is 2-butanone, methyl acetate or ethyl acetate.

11. A process as claimed in any one of claims 8 to 10, wherein the organic solvent has a water content of 2% v/v.

12. The method of any one of claims 8 to 10, wherein the solution is heated from 50 ℃ to 80 ℃.

13. The method of claim 11, wherein the solution is heated from 50 ℃ to 80 ℃.