4-Methylene-1,3-dioxolanes - obtd. by dehydrobromination of a 4-bromomethyl dioxolane and used as anti bronchoconstrictors, anticholinergics, etc.

摘要

Dioxolanes are of formula (I): (where either R1 is CH3; and R2 = 3,4,5-trimethoxy phenyl or R1CR2 is a gp. (IIa) or (IIb). (where --- is an opt. double bond). (I) are used as anti-bronchoconstrictors, anticholinergics, cardiac analeptics and analgesics; and may be prepd. by dehydrohalogenation of cpd. (I: = CH2 is -CH2Br), eg by NaH in hexamethyl phosphonotriamide in presence of N-methyl aniline.