Process for preparing purine derivative
OwnerAsif Parvez Sayyed, Murali Krishna Ankaraju +4inventors
InventorsAsif Parvez Sayyed, Murali Krishna Ankaraju, Ravinder Reddy Vennapureddy, Shankar Rama, Ramesh Dandala, Sivakumaran Meenakshisunderam
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Abstract
A process for the preparation of famciclovir a compound of Formula (I) and its intermediates.
Claims45
1) A process for preparing a compound of Formula II,
- wherein R1 and R2 represents hydroxy protecting group selected from the group C6H5CH2—,
- acetonide, acetal of 1,3-dioxane such as
- R3 and R4 is selected from hydrogen, C1-5 alkyl, C3-8 cycloalkyl, substituted or unsubstituted aryl
- which comprises:
- i) reacting a compound of Formula III
- wherein R1 and R2 is same as defined above
- with a compound of Formula IV
- in the presence of a base and a solvent to give a compound of Formula V
- wherein R1 and R2 is same as defined above
- ii) reducing a compound of Formula V to give a compound of Formula II.
7) (canceled)
8) A compound of Formula V
- wherein R1 and R2 represents hydroxy protecting group selected from the group C6H5CH2—,
- acetonide, acetal of 1,3-dioxane such as
- R3 and R4 is selected from hydrogen, C1-5 alkyl, C3-8 cycloalkyl, substituted or unsubstituted aryl.
9) A compound of Formula IX
- wherein R1 and R2 represents hydroxy protecting group selected from the group C6H5CH2—,
- acetonide, acetal of 1,3-dioxane such as
- R3 and R4 is selected from hydrogen, C1-5 alkyl, C3-8 cycloalkyl, substituted or unsubstituted aryl.
10) The compound 3,3-bis(benzyloxymethyl)propionitrile of Formula C isolated with a purity greater than 98% as measured by Gas Chromatography.
11) A compound of Formula X
14) A process for the preparation of Famciclovir of Formula I
- which comprises
- a) condensing the compound of Formula II,
- wherein R1 and R2 is same as defined above
- with a compound of Formula XII,
- in the presence of base in a solvent to give compound of Formula IX,
- b) dechlorinating and deprotection of the compound of Formula IX using a catalyst in a solvent to obtain a compound of Formula X,
- c) cyclizing the compound of Formula X with trialkylorthoformate in the presence of an acid to give compound of Formula XI,
- d) acylating the compound of Formula XI with a suitable acylating agent to give compound of Formula I.
30) A process for the preparation of Famciclovir of Formula I
- which comprises
- a) deprotecting the compound of Formula II,
- wherein R1 and R2 is same as defined above
- to give compound of Formula VIII or a salt thereof
- b) condensing the compound of Formula VIII or a salt thereof with a compound of Formula XII,
- in presence of base in a solvent to give compound of Formula XIII,
- b) dechlorinating the compound of Formula XIII using a catalyst in a solvent to obtain a compound of Formula X,
- c) cyclizing the compound of Formula X with trialkylorthoformate in the presence of an acid to give compound of Formula XI,
- e) acylating the compound of Formula XI with a suitable acylating agent to give compound of Formula I.
Dependencies are inferred from the claim text.