FORM 2THE PATENT ACT 1970(39 of 1970)&The Patents Rules, 2003COMPLETE SPECIFICATION(See section 10 and rule13)
1. TITLE OF THE INVENTION:A PROCESS FOR THE PURIFICATION OF ADENOSINE
2. APPLICANT (S)(a) NAME: WOCKHARDT LTD.(b) NATIONALITY: INDIAN(c) ADDRESS: Wockhardt Towers, Bandra-Kurla Complex, Bandra(East), Mumbai - 400 051.
3. PREAMBLE TO THE DESCRIPTIONThe present invention provides the purification process of adenosine to obtain pharmaceutical^ pure adenosine
The following specification particularly describes the invention and the manner in which it is to be performed.

4. DESCRIPTION
The present invention provides a process for the purification of adenosine having no impurities are more than 0.1%.
Adenosine of Formula I is chemically designated as 9-(β-D-Ribofuranosyl-9H-purin-6-amine and additional names are 6-amino-9-(β-D-ribofuranosyl-9H-purine; 9-β-D-ribofuranosidoadenine; adenine riboside. It is indicated for the treatment of the signs and symptoms of arrhythmia, hyperlipemia and cardiac infarction.

Adenosine is a naturally occurring nucleoside composed of the purine, adenine, and the sugar, D-ribose. In addition, it is commonly present in the body in the form of adenosine monophosphate (AMP), adenosine diphosphate (ADP) and adenosine triphosphate (ATP). Adenosine is manufactured from yeast nucleic acid.
Journal of medical chemistry, 30(6), 982-991, (1987), describes a process for the preparation of adenosine. It discloses a process for the preparation adenosine by condensation of tetra-O-acetyl ribofuranose with adenine. The obtained
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condensed product is further converted to adenosine. Adenosine obtained by this process having more than 0.1% impurities.
The present inventors have surprisingly found an efficient process for purification of adenosine, to get the synthetically produced adenosine of high purity. The process of present invention is cost-effective and easily scalable at commercial scale.
In one of the aspect of the present invention there is provided a process for purification of adenosine wherein the said process comprises of,
a) adding base to suspension or solution of adenosine
b) heating the resultant mixture,
c) isolating the adenosine from reaction mass thereof.
In another aspect of the present invention there is provided synthetically produced adenosine having purity 99.8% or more when measured by HPLC. To attain adenosine of such purity is difficult without using preparative HPLC technique.
Adenosine can be prepared by methods known in the art. The said adenosine containing impurities in the form of solution or suspension was treated with base at higher temperature. The mass is cooled and the separated product was isolated. The product obtained was dried to get pure adenosine having HPLC purity of 99.8% or more.
Base may be selected from a group comprising one or more of sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, triethylamine, methylamine, and ammonia solution.
While the present invention has been described in terms of its specific embodiments, certain modifications and equivalents will be apparent to those
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skilled in the art and are intended to be included within the scope of the present invention.
Example 1
Purification of adenosine
Crude adenosine (120 gm) was added to water (1.2 lit) and aqueous ammonia
solution (24% w/v) under reflux at about 80-90°C. The mass was cooled and the
separated product was isolated at about 10-15° C. The wet product obtained was
dried to get pure adenosine.
Yield: 80-90 gm
Purity: 99.99% (by HPLC)
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WE CLAIM:
1. A process for purification of adenosine wherein the said process comprises
of,
a) adding base to suspension or solution of adenosine
b) heating the resultant mixture,
c) isolating the adenosine from reaction mass thereof.

2. A process according to claim 1 wherein the base is inorganic or organic base.
3. A process according to claim 2 wherein base is ammonia.
4. A process according to claim 1 wherein adenosine so obtained having purity 99.8% w/w or more by HPLC.
Dated this 29TH day of September, 2006 For Wockhardt Limited

(Mandar Kodgule) Authorized Signatory
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