Patent ID: 8263755
Filing Date: 2012-09-11
Classification: A61P,C07J

Abstract:
1. A method for preparing a compound of formula I: or a pharmaceutically acceptable salt thereof, wherein: each of Ring A, Ring B, Ring C, Ring D, and Ring E is independently saturated, partially unsaturated or aromatic; G is S, CH R each R is independently hydrogen, an optionally substituted C n is 0-2; R m is 0-2; R each T is independently a valence bond or an optionally substituted straight or branched, saturated or unsaturated, C each R′ and R″ is independently selected from R, OR, SR, SO R Q is a valence bond or an optionally substituted straight or branched, saturated or unsaturated, C comprising the steps of: (a) providing a compound of formula II:  and (b) converting the compound of formula II to the compound of formula I, where the conversion is achieved by intramolecular dehydration reaction.