Find in Library

Hollongdione is the first recorded example of the occurrence of a dammarane hexanor-triterpene in nature possessing antiviral and cytotoxic activity. Its simple one-stage transformation into compounds with terminal alkyne and vinyl chloride fragments via the interaction with phosphorus halides is reported. The copper(I)-catalyzed Mannich reaction of 3-oxo-22,23,24,25,26,27-hexanor-dammar-20(21)-in <b>3</b> led to a series of aminomethylated products, while 17-carboxylic acid was obtained by ozone oxidation of 3-oxo-22,23,24,25,26,27-hexanor-dammar-20-chloro-20(21)-en <b>4</b>; the following direct amidation of the latter has been developed. The structures of all new molecules were established by spectroscopic studies that included 2D NMR correlation methods; the molecular structures of compounds <b>2</b>–<b>5</b> were determined by X-ray analysis.