Abstract
The acid-catalysed dehydration of some 4-amino-1, 2-diarylbutan-2-ols yields all four possible 4-amino-1, 2-diarylbutenes. The structure and configuration of pure isomers have been established from spectroscopic data, and the ability of these compounds to anatagonize histamine-induced contractions of the guinea-pig ileum is reported. The most potent derivatives are all cis(H/Ar)-4-amino-1, 2-diarylbut-2-enes. These results together with other data are discussed in terms of the possible structural and conformational requirements of histamine antagonists.