Title of Invention

AN IMPROVED PROCESS FOR THE PREPARATION OF THYMIDINE DERIVATIVE

Abstract

The present invention provides an improved and economical method for the preparation of 3’-azido-3’ –deoxy-5’ –trityl thymidine of formula (I-A). The present invention further provides a simple and industrially useful method for the preparation of 3’ –azido-3’ –deoxy-5’ – trityl thymidine of formula (I-A), in a single-pot, which comprises the reaction of beta-thymidine (II) with trityl choride in presence of base utilizing an inert organic solvent to give a 5’ –O-tritylthymidine of formula (III), which on reaction with methanesulphonyl chloride in the same pot gives 5’ –O-trityl 3’ –O-mesylthymidine, which on subsequent cyclization with an inorganic base gives 5’-O-trityl-2,3’-anhydrothymidine (V). Thus, 3’ –azido-3’ –deoxy-5’ –O-tritylthymidine (VI), prepared from 5’ –O-trityl-2,3’ –anhydrothymidine (V), without isolation is allowed to react with sodium azide in presence of ammonium chloride to give 3’ –azido-3’ –deoxy-5’-trityl thymidine of formula (I-A).

Full Text

Documents:

91-MUM-2005-ABSTRACT(5-5-2009).pdf

91-MUM-2005-ABSTRACT(AMENDED)-(5-5-2009).pdf

91-mum-2005-abstract(granted)-(24-6-2009).pdf

91-MUM-2005-CANCELLED PAGES(5-5-2009).pdf

91-MUM-2005-CLAIMS(30-12-2005).pdf

91-MUM-2005-CLAIMS(5-5-2009).pdf

91-mum-2005-claims(granted)-(24-6-2009).pdf

91-MUM-2005-CORRESPONDENCE(5-5-2009).pdf

91-MUM-2005-CORRESPONDENCE(7-7-2006).pdf

91-MUM-2005-CORRESPONDENCE(IPO)-(14-7-2009).pdf

91-MUM-2005-DESCRIPTION(COMPLETE)-(30-12-2005).pdf

91-MUM-2005-DESCRIPTION(COMPLETE)-(5-5-2009).pdf

91-mum-2005-description(granted)-(24-6-2009).pdf

91-MUM-2005-DESCRIPTION(PROVISIONAL)-(28-1-2005).pdf

91-MUM-2005-FORM 1(28-1-2005).pdf

91-MUM-2005-FORM 1(30-12-2005).pdf

91-MUM-2005-FORM 1(30-2-2005).pdf

91-MUM-2005-FORM 1(5-5-2009).pdf

91-MUM-2005-FORM 18(7-7-2006).pdf

91-mum-2005-form 2(5-5-2009).pdf

91-MUM-2005-FORM 2(COMPLETE)-(30-12-2005).pdf

91-mum-2005-form 2(granted)-(24-6-2009).pdf

91-MUM-2005-FORM 2(PROVISIONAL)-(28-1-2005).pdf

91-MUM-2005-FORM 2(TITLE PAGE)-(5-5-2009).pdf

91-MUM-2005-FORM 2(TITLE PAGE)-(COMPLETE)-(30-12-2005).pdf

91-mum-2005-form 2(title page)-(granted)-(24-6-2009).pdf

91-MUM-2005-FORM 2(TITLE PAGE)-(PROVISIONAL)-(28-1-2005).pdf

91-MUM-2005-FORM 26(5-5-2009).pdf

91-MUM-2005-FORM 3(28-1-2005).pdf

91-MUM-2005-FORM 3(30-12-2005).pdf

91-MUM-2005-FORM 5(28-1-2005).pdf

91-MUM-2005-FORM 5(30-12-2005).pdf

91-MUM-2005-PETITION UNDER RULE 137(5-5-2009).pdf

91-MUM-2005-SPECIFICATION(AMENDED)-(5-5-2009).pdf

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