Studies on some biologically important compounds

Abstract

Investigations on P. tabacina infected tobacco plants has resulted in the isolation of a highly active inhibitor of P. tabacina germination. The inhibitor, named Quiesone, was isolated via ethanolic extraction of infected leaves, countercurrent distribution, silica gel and alumina column chromatography, and gas chromatography on SE-52 and carbowax 20M. The isolation was monitored by biological assay against P. tabacina germination. The small weight of Quiesone isolated necessitated that the structure be derived from spectroscopic data. This indicated that Quiesone was 4- (4-hydroxy-2,6, 6-trimethyl-l-cyclohexen-l-yl)-3-buten-2-one butyrate. A possible biological role for Quiesone is discussed. Studies on the synthesis of the dimethoxy derivatives of mycelianamide and related compounds showed that when the formation of the benzylidene linkage was attempted by elimination of a methyl sulphoxide group, the methoxy group attached to the nearest nitrogen atom was also eliminated. In order to gain more insight into the elimination of the methoxy group the synthesis of the model compound 4a,8-diphenyl-l-methoxy- 2-oxo Δ8,8a octahydroquinoline was attempted. Show more