Sch 39304 is a new broad-spectrum orally active triazole antifungal agent that is active, orally and topically, against a broad range of fungal pathogens, including superficial Trichophyton mentagrophytes and vaginal Candida albicans infections. The mechanism of action of SCH-39304 appears similar to those of ketoconazole and fluconazole, involving inhibition of cell membrane ergosterol synthesis. SCH-39304 has two asymmetrical carbon atoms, and the formulation used in clinical trials has been a racemic mixture of two enantiomers, active SCH-42427 (RR (+)-) and inactive SCH-424264 (SS (–)-). Unfortunately, hepatocarcinomas associated with the use of SCH-39304 in animals have sharply restricted the development and use of this agent.

METHOPHOLINE, an isoquinoline derivative, is an opioid analgesic drug. Its (R)-enatiomer is approximately six times more potent than codeine, and (S)-enantiomer is inactive. METHOPHOLINE was withdrawn from the market for reasons of safety.

Crotamiton is a scabicidal and antipruritic agent available as a cream or lotion for topical use. The drug was approved by FDA for the treatment of scabies and pruritic skin. Crotamiton is a mixture of the cis and trans isomers of N-ethyl-N-(o-methylphenyl)-2butenamide. Although the activity of crotamiton was shown both in vitro and in vivo, the mechanism of its action is still unknown.

Broparestrol, (Z)- is an isomer of Broparestrol -- synthetic, nonsteroidal selective estrogen receptor modulator (SERM) of the triphenylethylene group that has been used in Europe as a dermatological agent and for the treatment of breast cancer. Broparestrol, (Z)- and Broparestrol, (E)- demonstrates antiestrogenic activity but, unlike broparestrol, were never marketed.