Patent ID: 7601838

Claim:
A compound of formula 1: wherein R is selected from the group consisting of the methyl ester, —C(O)OCH 3 , and the amide, —C(O)NH 2 ; and R 1 is selected from the group consisting of (a) a C 1 to C 10 alkyl; (b) an aryl selected from the group consisting of: unsubstituted phenyl, phenyl substituted by a moiety selected from the group consisting of halogen, alkyl, and alkoxy, unsubstituted naphthyl, naphthyl substituted by dimethyl amino; and (c) quinoline provided that when R is —C(O)OCH 3 , (b) is not tolyl an unsubstituted phenyl or a phenyl substituted by an alkyl.