| abstract |
1. A compound of the formula (II):n or a pharmaceutically acceptable salt or pharmaceutically acceptable ester thereof, wherein R 1 is hydrogen, -CHO or -SO 3 H or a pharmaceutically acceptable salt thereof, R 2 is C 1-6 alkyl or benzyl, and R 3 is an optionally substituted pyrimidinyl group. Processes for the preparation of such compounds and pharmaceutical compositions containing these compounds are also disclosed. |