Field of the invention:
The present invention relates to pharmaceutical composition of prasugrel or its pharmaceutically acceptable salts thereof, especially hydrochloride salt.
Prasugrel is chemically known as 2-acetoxy-5-cyclopropylcarbonyl-2-fluorobenzyl)-4,5,6,7-tetrahydrothieno[3,2-c]pyridine is represented by structural formula-1.

The present invention also relates to an improved process for the preparation of prasugrel and its pharmaceutically acceptable salts. It further relates to the method for the formulation of prasugrel hydrochloride.
Background of the invention:
Prasugrel is a thienopyridine derivative, and an ADP receptor antagonist. Prasugrel is an inhibitor of platelet activation and aggregation through the irreversible binding of its active metabolite to the P2Y12 class of ADP receptors on platelets. It produces more potent platelet inhibition, a rapid onset of action and may provide a superior therapeutic alternative to clopidogrel.
Prasugrel hydrochloride is marketed in Europe as Efient and in US as Effient for the treatment of patients with acute coronary syndrome who are managed with percutaneous coronary intervention.
US 5,288,726 disclose tetrahydrothienopyridine derivatives including prasugrel. This patent document discloses the use of these compounds for the treatment and prophylaxis of thrombosis and embolisms.
US 6,693,115 disclose the hydrochloric acid and maleic acid salts of prasugrel. The hydrochloride and maleate salt forms provide unexpected and unobvious

improvements in their efficacy and stability profiles compared to other salts and also compared to fi-ee base molecule. However, prolonged exposure of prasugrel to ah: and moisture results in degradation. Hence, there is need for unprovements in the stability, shelf life and therefore long term efficacy of individual doses of prasugrel.
International publication number WO 2006/135605 describes a formulation comprising a therapeutically effective amount of prasugrel hydrochloride packaged in an air and moisture impervious blister package, with an inert gas atmosphere, to improve the stability and shelf life of prasugrel.
International publication number WO 2008/073759 describes a formulation comprising packaging prasugrel tablet, capsule, caplet or other solid form of prasugrel in an air and/or moisture impervious container imder a positive liquid gas pressure, to enhance the stability and shelf life of prasugrel.
European patent application number EP 2,100,607 describes a pharmaceutical composition comprising prasugrel or pharmaceutically acceptable salt thereof; and a water-soluble polymer selected fi-om the group consisting of hydroxypropyl methyl cellulose, hydroxypropyl cellulose and polyvinyl pyrrolidone,
European patent application number EP 2,100,608 describes a method for producing a solid preparation containing prasugrel or pharmaceutically acceptable salt thereof is mixed, while applying mechanical stress to the composition.
European patent application number EP 2,100,609 describes a solid medicinal preparation, which comprises prasugrel or pharmaceutically acceptable salt thereof; and mannitol or lactose which, when examined under conditions, has a particle size distribution in which the 90% cumulative diameter is 80 to 300 pm.
European patent application number EP 2,100,610 describes a pharmaceutical composition comprising prasugrel or pharmaceutically acceptable salt thereof; and a low-substituted hydroxypropyl cellulose.

U.S. patent application number 2009/0281136 describes a pharmaceutical formulation comprising prasugrel or pharmaceutically acceptable salt thereof; and at least one stabilizing agent.
According to the invention, the pharmaceutical composition is in the form of a tablet, in which pregelatinized starch is used as a binder enhancing the crushing strength and dissolution profile. The use of ethyl cellulose a hydrophobic polymer in the coating material, provides a protective layer against absorption of moisture. The tablets are packed in alu-alu cold packing which has no air gap in the pocket of aluminium blister preventing any moisture being present in the atmosphere around the tablet.
Brief Description of Invention:
The present invention relates to a pharmaceutical composition of prasugrel and its pharmaceutically acceptable salts.
The first aspect of the present invention is to provide a pharmaceutical composition of prasugrel or its pharmaceutically acceptable salts, which comprises of;
a) the active pharmaceutical ingredient,
b) a water insoluble dry binder,
c) at least one diluent
d) at least one disintegrant
e) at least one lubricant, and
f) optionally coated with a film.
In an embodiment the pharmaceutical composition is in the form of a tablet which is coated with a film impregnated with ethyl cellulose a hydrophobic polymer, which protects the pharmaceutical composition firom moisture. The composition is prepared by dry granulation method.
The tablets are packed in alu-alu cold packing in order to avoid the pharmaceutical composition fi-om being exposed to moisture.

The second aspect of the present invention is to provide a process for purification of compound of fonnula-3, which comprises of;
a) suspending the compound of formula-3 in a suitable solvents or mixture of solvents;
b) heating the suspension to reflux,
c) cooling the suspension,
d) filtering the suspension to get the compound of fonnula-3.
The third aspect of the present invention is to provide an improved process for the preparation of prasugrel and its pharmaceutically acceptable salts, which comprises of;
a) Removing the protecting group on nitrogen from N-trityl 5,6,7,7a-tetrahydro-4H-thieno[3,2-c] pyridine-2-one compound of formula-2,by treating with an hydrochloric acid in acetone to provide corresponding 5,6,7,7a-tetrahydro-4H-thieno[3,2-c] pyridine-2-one hydrochloride salt, which on purification in a mixture of dichloromethane and methanol to obtain highly pure compound of formula-3,
b) reacting the hydrochloride salt of 5,6,7,7a-tetrahydro-4H-thieno[3,2-c]pyridine-2-one hydrochloride compound of formula-3 with a-cyclopropylcarbonyl-2-fluorobenzyl bromide compound of formula-4, in presence of potassium carbonate in a acetonitrile, followed by treatment with hydrobromic acid to provide a compound of formula-5,
c) acetylating the compoimd of formula-5 with a suitable acetic anhydride in the presence oftriethylamine to provide prasugrel compound of formula-1,
d) converting the prasugrel into its hydrochloride by treating with a hydrochloric acid compound of formula- la, in acetone and ethyl acetate solvent.
The fourth aspect of the present invention is to provide a process for the preparation of crystalline form-B2 of prasugrel hydrochloride
Detailed description of the invention:
The present invention relates to a pharmaceutical composition of prasugrel and its pharmaceutically acceptable salts.

The first aspect of the present invention is to provide a pharmaceutical composition of prasugrel or its pharmaceutically acceptable salts, which comprises of;
a) the active pharmaceutical ingredient,
b) a water insoluble dry binder,
c) at least one diluent
d) at least one disintegrant
e) at least one lubricant, and
f) optionally coated with a film.
In an embodiment the pharmaceutical composition is in the form of a tablet which is prepared by dry granulation and direct compression method. The tablet is coated with a film which protects the pharmaceutical composition form coming into contact with moisture avoiding degradation of the active pharmaceutical ingredient. Further the tablets are packed in alu-alu cold packing without leaving an air gap in the pockets of aluminium blister, which prevents the pharmaceutical composition fi-om being exposed to air which may contain moisture, thereby avoids the formation of impurities and increase stability and shelf life of prasugrel.
When ethyl cellulose a hydrophobic polymer is added to the coating material it enhances the protective properties of the film coating against moisture.
As used herein the term "Prasugrel" means a compound including, but not limited to, the drug compound prasugrel, its pharmaceutical acceptable salts and their polymorphs and hydrates thereof
The term "pharmaceutically acceptable salts" refers to salts including but not limited to, hydrohalides like hydrochloride, hydrobromide and hydroiodide; inorganic acids such as nitrate, perchloric acid salt, sulfate or phosphate; lower-alkyl sulfonic acid salts such as methanesulfonate, or ethanesulfonate; arylsulfonic acid salts such as benzene sulfonate or p-toluenesulfoante; organic acid salts such as acteate, malate, fimierate, succinate, citrate, ascorbate, tartarate, oxalate or maleate; or an amino acid salts such as glycine salt, lysine salt, arginine salt, ornithine salt, glutamic acid salt or aspartic

acid salt, preferably hydrohalides or organic acid salts, more preferably hydrochloride or maleate and most preferably hydrochloride.
In a preferred embodiment of the present invention provides a pharmaceutical composition of prasugrel, which comprises of;
a) prasugrel hydrochloride,
b) the water insoluble dry binder is pregelatinized starch,
c) the diluent is microcrystalline cellulose,
d) the disintegrant is croscarmellose sodium,
e) the lubricant is magnesium stearate and
f) coated with a film comprising of hydroxypropyl cellulose, polyethylene glycol, titanium dioxide, color and ethyl cellulose.
The formulation according to the invention preferably comprises fi-om 2 to 20%, most preferably fi"om 5 to 10%, of prasugrel or its salts and/or hydrates thereof (all the percentages are % by weight based on the weight of the pharmaceutical preparation).
The pharmaceutical composition of the present invention contains binders, diluents, disintegrants, lubricants and/or coating materials.
The "diluents" that may be used include but are not limited to, cellulose derivatives such as microcrystalline cellulose, phosphates such as dibasic calcium phosphate anhydrous, tricalcium phosphate anhydrous, sulfates such as calcium sulfate
i
and silicified microcrysline cellulose. Particular preference according to the invention is given using microcrystalline cellulose having the diameter in the range of 420 microns to 105 microns, which increases greater compressibility and more resistance towards crushing strength. The pharmaceutical preparation advantageously comprises from 50 to 96%, preferably from 60 to 95%, particularly preferably from 70 to 90% of the diluents.
The "binders" that may be used include but are not limited to, starch derivatives such as pregelatized starch, polymers such as carbomer, chitosan. Particularly preference according to the invention is given using pregelatinized starch. The pharmaceutical

preparation advantageously comprises from 1 to 25%, preferably from 1.5 to 20%, particularly more preferably from 2 to 16% of the binders.
The "disintegrants" that may be used may be, selected from the group consisting of starch, starch glycolates, crosslinked polyvinylpyrrolidone and sodium carboxymethylcellulose (croscarmellose sodiirai). Particular preference according to the invention is given to using croscarmellose sodium. The pharmaceutical preparation advantageously comprises from 1 to 10%, preferably from 1.5 to 8%, particularly preferably from 2 to 6% of the disintegrant.
The "lubricants" that may be used include but are not limited to, stearic acid, stearic acid metal salts such as magnesium stearate or calcium stearate; talc; colloidal silica; waxes such as bee's wax or spermaceti; boric acid; adipic acid; sulfates such as sodium sulfate glycol; fumeric acid; sodium steryl fimierate. Particular preference according to the invention is given to using magnesium stearate.The pharmaceutical preparation advantageously comprises from 0.05 to 1.5%, preferably from 0.2 to 1.2%, particularly preferably from 0.5 to 1% of the lubricant.
As the "coating agents" used, may be selected fix)m hydroxypropyl cellulose, hydroxymethyl cellulose, ethyl cellulose, talc, polyethylene glycol, titanium dioxide and color.
The pharmaceutically composition of the present invention is preferably in the form of solid preparation for example, tablets, capsules, granules, fine granules, powders, pills, chewables or troches. Preferably, it is in the form of powders, granules, fine granules, capsules or tablets and most preferably tablets.
The present invention utilizes the dry method for formulation which is more advantageous as prasugrel and its salts are moisture sensitive.
The dry method of the present invention involves dry granulation and the direct compression method.

The "dry granulation method" is a method in which a preparation is produced by using granules prepared by crushing and dividing by an appropriate method by compress-molded slug or sheet of raw material powders.
The "direct compression method" is a method which raw material powders are directly subjected to compression-molding to produce a preparation.
The dosage of the compound represented by the aforementioned general formula (I) or pharmacologically acceptable salt thereof, which is an active ingredient of the pharmaceutical composition of the present invention, may vary depending on various conditions such as the activity of the drug, symptoms, age or body weight of a patient. The daily dosage amount for an adult human has a lower limit of 0.01 mg (preferably 1 mg) and an upper limit of 200 mg in the case of oral administration (preferably 100 mg).
Prasugrel and its pharmaceutically acceptable salts used in the present mvention can be taken from those prepared by the processes cited in the prior art. Prasugrel and its pharmaceutically acceptable salts can be prepared according to the improved process illustrated in the present invention.
The second aspect of the present invention provides a process for purification of 5,6,7,7a-tetrahydro-4H-thieno[3,2-c] pyridine-2-one hydrochloride salt compound of fonnula-3, which comprises of:
a) suspending the compound of formula-3 in a suitable solvent selected from chloro solvents like dichloromethane, chloroform and 1,2-dichloroethane; alcoholic solvents like methanol, ethanol,l-propanol, isopropyl alcohol and n-butanol or mixtures thereof, preferably in a mixture of dichloromethane and methanol,
b) heating the suspension to reflux,
c) cooling the suspension,
d) filtering the solid to get highly pure compound of formula-3.
All the reported processes for the preparation of prasugrel involve the usage of compound of formula-3, which is having very low quality and hence lead to the formation of corresponding impurities in fiirther steps. So far no purification technique

has been reported for the compound of formula-3. While working to resolve this issue it was surprisingly found that the purification of compound of formula-3 in a mixture of dichloromethane and methanol provided the compound of formula-3 with very high quality in terms of its assay. Here highly pure compound means, a compound having purity greater than 95%, preferably greater than 98%, more preferably 99.00% by HPLC and having assay greater than 95%, preferably greater than 98%, more preferably 99%.
When the highly pure compound of fonnula-3 prepared by the present invention is used in the preparation of prasugrel or its pharmaceutically acceptable salts it provides the final compounds with high yields and purity. In particular, the yield of condensation reaction between the compound of formula-3 with a-cyclopropylcarbonyl-2-fluorobenzyl bromide compound of formula-4 substantially increased.
The third aspect of the present invention is to provide an improved process for the preparation of prasugrel and its pharmaceutically acceptable salts, which comprises of;
a) Removing the protecting group on nitrogen fi-om N-trityl 5,6,7,7a-tetrahydro-4H
thieno[3,2-c] pyridine-2-one compound of formula-2,

by treating with hydrochloric acid in acetone to provide corresponding 5,6,7,7a-tetrahydro-4H-thieno[3,2-c] pyridine-2-one hydrochloride salt, which on purification in a mixture of dichloromethane and methanol provides a highly pure compound of formula-3,

b) reacting the hydrochloride salt of 5,6,7,7a-tetrahydro-4H-thieno[3,2-c]pyridine-2-one
hydrochloride compound of formula-3 with a-cyclopropylcarbonyl-2-fluorobenzyl
bromide compound of formula-4.


in presence of potassium carbonate in a acetonitrile, followed by treatment with hydrobromic acid to provide a compoimd of formula-5,

c) acetylating the compoimd of formula-5 with a suitable acetic anhydride in the
presence oftriethylamine to provide prasugrel compoimd of fonnula-1,

d) converting the prasugrel into its hydrochloride salt by treating with a hydrochloric
acid in acetone and ethyl acetate solvent.
Three different crystalline forms A, Bi and B2 of prasugrel hydrochloride are known in the art. The disclosed process involves the usage of acetone solvent and aqueous hydrochloric acid for the preparation of said crystalline forms. When the reported process was repeated with the exception that dry hydrochloric acid in ethylacetate was used in place of aqueous hydrochloric acid it provided prasugrel

hydrochloride the physical characteristics of which matched completely with known crystalline form B2 of prasugrel hydrochloride.

The fourth aspect of the present invention is to provide a process for the preparation of crystalline form-Ba of prasugrel hydrochloride, which comprises of;
a) dissolving the prasugrel in acetone,
b) heating the solution and subjected to carbon treatment,
c) cooling the solution,
d) adding ethylacetate hydrochloride,
e) filtering the solid to get the crystalline form-B2 of prasugrel hydrochloride.

Dissolution test of the pharmaceutical composition prepared in the invention in

The dissolution profile conducted in three dififerent media indicates that O.OIN HCl has got more discriminatory power comparative with other dissolution mediums. The formulation prepared according to the present invention is equivalent to the in-vitro studies of the innovator's drug.

The process described in the present invention was demonstrated in examples illustrated below. These examples are provided as illustration only and therefore should not be construed as limitation of the scope of the invention. Examples:

Manufacturing process:
Prasugrel hydrochloride and all excipients were shifted through #40 mesh sieve and mixed thoroughly, Prasugrel hydrochloride was mixed with 1:1 proportion microcrystalline cellulose, mixed pregelatinized starch and croscarmellose sodium by using blender. Then blend with remaining microcrystalline cellulose followed by magnesium stearate. The blend was then subjected to compression on machine to make tablets.
The cores were aqueous coated in a coating pan with hydroxypropyl cellulose, polyethylene glycol, titanium dioxide and color.


Manufacturing process:
Prasugrel hydrochloride and all excipients were shifted through #40 mesh sieve and mixed thoroughly, Prasugrel hydrochloride was mixed with 1:1 proportion microcrystalline cellulose, mixed pregelatinized starch and croscarmellose sodium by using blender. Then blend with remaining microcrystalline cellulose followed by magnesium stearate. The blend was then subjected to compression on machine to make tablets.
The cores were aqueous coated in a coating pan with hydroxypropyl cellulose, polyethylene glycol, ethyl cellulose, titanium dioxide and color.
Example-5: Purification of 5,6,7,7a-tetrahydro-4H-thieno[3;j-cl-pyridm-2-one-hydrochloride
A mixture of dichloromethane (425 ml), methanol (75 ml) and 5,6,7,7a-tetrahydro-4H-thieno[3,2-c]-pyridin-2-one-hydrochloride (100 grams) was heated to reflux. The reaction mixture was stirred for 30 mmutes and cooled to 25-30°C and further stirred for

1 hour. The solid obtained was filtered, washed with dichloromethane and dried to get the
title compound.
Yield: 88 grams; Assay: 98.5%.
Exainple-6: Preparation of 5-(2-cyclopropyl-l-(2-fluorophenyI)-2-oxoethyl)-5,6,7,7a-tetrahydrothieno[3,2-c]pyridine-2(4H)-oiie hydrobromide
A mixture of 5,6,7,7a-tetrahydro-4H-thieno[3,2-c]-pyridin-2-one-hydrochloride (100 grams), potassium carbonate (215 grams) and acetonitrile (1750 ml) was stirred for 30 minutes at 25-30°C. 2-bromo-l-cyclopropyl-2-(2-fluorophenyl) ethanone (85.5 grams) in acetonitrile (50 ml) was added to the reaction mixture and stirred for 6 hours at 25-30°C. The precipitated solid was removed by filtration. Silica gel (200 grams) was added to the filtrate and stirred for 30 minutes and filtered. The filtrate was distilled off completely under reduced pressure and ethyl acetate followed by cyclohexane was added to it. The reaction mixture was stured for 25 minutes at 25-30°C. Added silica gel (150 grams) to the reaction mixture and stirred for 30 minutes at 25-30''C. The reaction mixture was filtered and solvent form the filtrate was distilled off completely under reduced pressure. Acetone (300 ml) was added to the obtained residue, stirred for 30 minutes and then cooled to 0-5°C. Aqueous hydrobromide (102 grams) was added to the reaction mixture at 0-5°C and stirred the reaction mixture at 25-30''C for 5 hours. The reaction mixture was cooled to 0°C and stirred for 2 hours. The solid formed was filtered, washed with acetone and dried to get the title compound. Yield: 84 grams; M.R.: 188-198°C.
ExampIe-7: Preparation of prasugrel compound of formula-1:
Triethylamine (98 grams) was added to the solution of 5-(2-cyclopropyl-l-(2-fluoro phenyl)-2-oxoethyl)-5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one hydrobromide (100 grams) in dichloromethane (1000 ml) and stirred for 15 minutes at 25-30°C and then cooled to 0-5°C. Acetic anhydride (62 grams) was added to the reaction mixture and stirred for 6 hours at 0-5°C. The reaction mixture was quenched with water at 20-25°C and separated both the aqueous and organic layers. Organic layer was washed with aqueous sodium bicarbonate followed by water and then the solvent from the organic

layer was distilled off under reduced pressure and isopropyl alcohol (125 ml) was added to the obtained residue and stirred for 45 min at 40-50°C. The reaction mixture was cooled to 10-15°C and stirred for 60 minutes. The solid obtained was filtered, washed with isopropyl alcohol and then dried to get the title compound. Yield: 84 grams,
Example-8: Preparation of Prasugrel hydrochloride crystalline form-B2:
Dissolved 5-(2-cyclopropyl-l-(2-fluorophenyl)-2-oxoethyl)-4,5,6,7-tetrahydrothieno [3,2-c] pyridin-2-yl acetate (100 grams) in acetone (800 ml) and then heated to 35-40°C. Carbon (5 grams) was added to the reaction mixture and stirred for 15 minutes. Filtered the reaction mixture and filtrate was cooled to 0-5°C and then ethyl acetate hydrochloric acid (500 ml) was added to it. Then the reaction mixture was stirred for 45 minutes at 0-5°C. The precipitated solid was filtered and washed with acetone. To the wet material added acetone (800 ml) and stirred for 45 minutes at 25-30°C. Filtered the reaction mixture, washed with acetone and dried the compound to get the title compound. Yield: 89 grams; Purity: 99.65% by HPLC
Example-9: Preparation of Prasugrel hydrochloride crystalline form-B2:
Dissolved 5-(2-cyclopropyl-l-(2-fluorophenyl)-2-oxoethyl)-4,5,6,7-tetrahydrothieno [3,2-c] pyridin-2-yl acetate (100 grams) in acetone (800 ml) and then heated to 35-40°C. Carbon (5 grams) was added to the reaction mixture and stirred for 15 minutes. Filtered the reaction mixture and filtrate was cooled to 0-5°C and ethyl acetate (500 ml) was added to it. Then hydrochloric acid gas was bubbled through it. The precipitated solid was filtered and washed with acetone. To the wet material added acetone (800 ml) and stirred for 45 minutes at 25-30°C. Filtered the reaction mixture, washed with acetone and dried the compound to get the title compound. Yield: 85grams; Purity: 99.5% by HPLC

We Claim:
1. A pharmaceutical composition of prasugrel or its pharmaceutically acceptable salts,
which comprises of;
a) the active pharmaceutical ingredient,
b) a water insoluble dry binder,
c) at least one diluent
d) at least one disintegrant,
e) at least one lubricant, and
f) optionally coated with a film,
2. A pharmaceutical composition of claim-1 wherein,
a) the active pharmaceutical ingredient is prasugrel hydrochloride,
b) the water insoluble dry binder is selected from starch, carbomer, and chitosan,
c) the diluent is selected from microcrystalline cellulose, dibasic calcium phosphate, tribasic calcium phosphate and calcium sulphate,
d) the disintegrant is selected from croscarmellose sodium, starch glycolates and crosslinked polyvinylpyrrolidone
e) the lubricant is selected from magnesium stearate and calcium stearate,
f) coating consisting of hydroxyl propyl methyl cellulose, poly ethylene glycol, titanium dioxide, color with/ without ethyl cellulose.

3. A pharmaceutical composition which comprises of prasugrel hydrochloride, microcrystalline cellulose, pregelatinizsed starch, croscarmellose sodium and magnesium stearate and coating consisting of hydroxyl propyl methyl cellulose, poly ethylene glycol, titanium dioxide, color with/ without ethyl cellulose.
4. A pharmaceutical composition of claims 1 to 4 wherein the pharmaceutical composition is in the form of a tablet is which is prepared by dry granulation and direct compression method.

5. A pharmaceutical composition of prasugrel hydrochloride in the form of a tablet, coated by a film containing ethyl cellulose a hydrophobic polymer.
6. The pharmaceutical preparation according to the invention comprises preferably from 1 to 25%, preferably from 1.5 to 20%, particularly more preferably from 2 to 16% of the binders.
7. A process for purification of compound of formula-3 comprise,

a) suspending the compound of formula-3 in dichloromethane and methanol,
b) heating the suspension to reflux,
c) cooling the suspension,
d) filtering the suspension to get highly pure compound of formula-3.

8. Thieno pyridine compoimd of formula-3 prepared as per the process claimed in claim 8 having purity greater than 98%.
9. An improved process for the preparation of prasugrel and its pharmaceutically acceptable salts, which comprises of;
a) Removing the protecting group on nitrogen from N-trityl 5,6,7,7a-tetrahydro-4H-thieno[3,2-c] pyridine-2-one compound of formula-2,

by treating with an hydrochloric acid m acetone to provide correspondmg 5,6,7,7a-tetrahydro-4H-thieno[3,2-c] pyridine-2-one hydrochloride salt, which on purification using dichloromethane and methanol to obtain a highly pure compound of formula-3,


b) reacting the hydrochloride salt of 5,6,7,7a-tetrahydro-4H-thieno[3,2-c]pyridine-2-
one hydrochloride compound of formula-3 with a-cyclopropylcarbonyl-2-
fluorobenzyl bromide compound of formula-4,

in presence of potassium carbonate in acetonitrile, followed by treatment with hydrobromic acid to provide a compound of formula-5,

c) acetylating the compound of formula-5 with a suitable acetic anhydride in the
presence oftriethylamine to provide prasugrel compound of formula-1,

d) converting the prasugrel into its hydrochloride salt by treating with a hydrochloric
acid in acetone and ethyl acetate solvent.
0. A process for the preparation of crystalline form-B2 of prasugrel hydrochloride, which comprises of;
a) dissolving the prasugrel in acetone,
b) heating the solution and subjected to carbon treatment,
c) cooling the solution,

d) adding ethylacetate hydrochloride,
e) filtering the solid to get the crystalline fonn-B2 of prasugrel hydrochloride.