Patent ID: 8835638

Claim:
A process for the preparation of 1,3-oxathiolane derivatives of Formula I and pharmaceutically acceptable salts thereof comprising cyclizing, in a first solvent and in the presence of a first acid, a compound of Formula VII or a salt thereof and optionally adding an acid of a pharmaceutically acceptable salt wherein R 2 is alkyl, substituted alkyl, aryl, substituted aryl, or arylalkyl; R 3 and R 4 are independently hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, or arylalkyl; and either (i) R 5 , R 6 and R 7 are independently hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, or substituted arylalkyl provided that at least one of R 5 and R 6 is alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, or substituted arylalkyl; (ii) R 5 and R 6 form a ring group together with the carbon to which they are bonded and R 7 is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl arylalkyl or substituted arylalkyl; or (iii) R 5 and R 7 form a ring group together with the carbons to which they are bonded and R 6 is hydrogen, alkyl, substituted alkyl, aryl, substituted aryl arylalkyl or substituted arylalkyl.