Patent ID: 6844338

Claim:
A compound of the formula: in which R 1 and R 2 are each hydrogen or C 1-6 alkyl, R 3 is —SR 10 , —SOR 10 , —SO 2 R 10 , —COR 10 , —CH 2 OH or —CONHR 11 , where R 10 is C 1-6 alkyl and R 11 is hydrogen or C 1-6 alkyl, R 4 , R 5 , R 6 and R 7 are each hydrogen or C 1-6 alkyl, provided that at least one of R 4 , R 5 , R6 and R 7 is C 1-6 alkyl, R 8 and R 9 are each hydrogen, halo, C 1-6 alkyl or cyano, n is 0 or 1 and m is 2 or 3, X is and Y is wherein R 12 and R 13 are each hydrogen, C 1-6 alkyl, cyclopropyl or cycopropyl-C 1-6 alkyl; and salts thereof.