摘要 |
<p>A process is provided for the preparation of a compound of Formula (1) wherein: R<1 >is H, optionally substituted acyl, optionally substituted alkyl, optionally substituted aryl or optionally substituted heteroaryl: R<2 >and R<3 >each independently are H or a hydroxy protecting group; comprising the steps: (a) reacting a compound of Formula (2) in a solvent in the presence of a base with a compound of formula R<4>SO2X to give a compound of Formula (3); wherein: R<4 >is an optionally substituted alkyl, optionally substituted aryl or optionally substituted heteroaryl group; and X is halogen: and (b) reacting the compound of Formula (3) with a cyanide source in the presence of a phase transfer catalyst.</p> |