<unk>  (Motofen, R-15403) is a 4-phenylpiperidine derivative that is related to the opioid analgesic drug pethidine (meperidine) and more distantly related to alphaprodine and piritramide, and it is an active metabolite of the anti-diarrhoea drug diphenoxylate.<unk>  et al. have a high peripheral/central actions ratio, working primarily on various opioid receptors in the intestines.<unk>  was developed in 1970 in Belgium at Janssen Pharmaceutica.
Difenoxin
Aflatoxin
Medigoxin
Rubratoxin
Clioquinol
Metobromuron
Cyclochlorotine
Rotenone