3 groups of r s r 2 r 3 r 4 and r 5 independently are h trifluoromethyl c 5 c 10 aryl c 5 c 10 heteroaryl c 1 c 10 alkyl c 2 c 10 alkenyl c 2 c 10 alkynyl c 3 c 10 cycloalkyl saturated c 5 c 10 heteroaryl c 5 c 10 aryl c 1 c 10 alkyl c 5 c 10 heteroaryl c 1 c 10 alkyl cor 7 c 0 2 r 7 conr 7 r 8 so 2 nr 7 r 8 said aryl heteroaryl alkyl alkenyl and cycloalkyl optionally substituted with 1 to 3 groups of r s r 7 and r 8 independently are h hydroxy c 1 c 10 alkyl c 2 c 10 alkenyl c 2 c 10 alkynyl c 3 c 10 cycloalkyl c 5 c 10 aryl c 5 c 10 heteroaryl said aryl heteroaryl alkyl alkenyl and cycloalkyl optionally substituted with 1 to 3 groups of r s r s represents a member selected from the group consisting of halo cyano nitro trihalomethyl carbamoyl hydroxy ocf 3 acyl aryl heteroaryl s o r 8 u2550 n or 8 so 2 r 8 coor 8 u2014.