Synthesis of Yuehchukene Analogues, Murrapanine and Normurrapanine Utylizing Thermal Reaction of b-(1-Hydroxybutenyl)indoles under Neutral Reaction Conditions

Abstract

p-(1-Hydroxybutenyl)indoles, which were prepared in high yields from indole-3-carboxaldehyde, could be converted into yuehchukene analogues(8a.bJ rnurrapanine(9a)and normumpanine(9b)in one step under thermal-induced reaction conditions in neutral solution of ethylene glycol and water.p-(1-Hydroxybutenyl)indoles are supposed to be dehydrated to I-(6-indolyl)-1,3butadienes which react further to yuehchukene analogues via a Diels-Alder pathway.Mumapanine and normumapanine showed a cytotoxicity toward KB cells.