A potential anti-implantation and spermicidal strategy: putative derivatives of nonoxynol-9 and anti-inflammatory agents and their spermicidal activity

Abstract Objectives We report the synthesis of novel ester derivatives of nonoxynol-9, an approved spermicidal agent, using the non-steroidal inflammatory drugs (NSAIDs) ibuprofen and indomethacin. Indomethacin has previously been shown to inhibit the implantation of the fertilised ovum into the uterus wall of pregnant rats. It is proposed that nonoxynol-9, in combination with a non-selective NSAID may exhibit both anti-implantation and spermicidal properties. Methods Both novel derivatives and nonoxynol-9 were then tested on boar spermatozoa in order to establish if spermicidal activity was retained following the esterification. Results The results showed that both the ibuprofen and indomethacin derivatives enabled complete cell death of boar spermatozoa at a concentration of 100 µg ml-1, which is comparable to nonoxynol-9 at the same concentration. Conclusions These results indicate that NSAID derivatives of nonoxynol-9 retain the activity of the parent molecule and may have other advantages associated with the molecular incorporation of the NSAID moieties and their anti-implantation activity. Keywords: Spermicide; Nonoxynol-9; Ibuprofen; Indomethacin; Boar spermatozoa; Contraceptive; Anti-implantation