Patent ID: 8193213

Claim:
A method for killing motile spermatozoa, comprising: contacting a spermatozoa containing composition with a spermicidal composition comprising a compound of formula I(a): wherein R 1 is hydrogen or straight-chain or branched C 1-6 alkyl or C 3 -C 8 cycloalkyl; R 2 is hydrogen, straight-chain or branched C 1-6 alkyl; R 3 and R 5 are each, independently, hydrogen, SO 3 H, straight-chain or branched C 1-6 alkyl, CH 2 OH, CH 2 OMe, straight chain or branched C 1-6 alkoxy, carboxyl (COOH), carboxylic acid ester (COOR where R is C 1-10 alkyl, C 6-10 aryl, C 7-10 aralkyl), hydroxymethyl ester (CH 2 OC(O)—R where R is as defined above), CONH 2 , CONHR, CONR 2 , CH 2 OCONHR, CN, CH═NHNHCONH 2 , and halogen; and R 4 is hydrogen, halogen, R 3 Si or COR, or a pharmaceutically acceptable salt thereof.