ond and R1 is phenyl, R2 is not methyl, methoxy, C(???O)CH3 or C(???O)H; when A is a direct bond and R1 is 4-Me-phenyl, R2 is not methyl; when A is a direct bond and R1 is 4-F-phenyl, R2 is not trifluoromethyl; when A is a direct bond or ???C???C??? and R1 is phenyl, R2 is not ???COOEt; and when A is a direct bond and R1 is 6,7-dimethoxyisoquinolin-1-yl, R2 is not hydroxy.