Naturally occurring prenylated coumarins from Micromelum integerrimum twigs

A phytochemical investigation of secondary metabolites from Micromelum integerrimum was reported. Two new prenylated coumarins named as hydramicromelin D (1) and integerrimelin (2) were isolated along with 9 known coumarin derivatives. The chemical structures as well as relative stereochemistries of those coumarins were confirmed on the basis of extensive spectroscopic data interpretation and comparison with those previously published data.     

New coumarins from Coleonema album

Six coumarins have been isolated from the aerial parts of Coleonema album and identified as ulopterol, 7-(3′, 3′-dimethylallyloxy)-coumarin, (R)-(+)-2′,3′-epoxy-suberosin, and the novel coumarins (R)-(+)-7-(2′, 3′-epoxy-3′-methylbutoxy)-coumarin, (R)-(+)-7-(2′,3′-dihydroxy-3′-dihydroxy-3′-methylbutoxy)-coumarin and (R)-(+)-7-methoxy-8-(2′,3′-epoxy-3′-methylbutoxy)-coumarin.     

Two new sesquiterpene coumarins from the seeds of Ferula sinkiangensis

Two new sesquiterpene coumarins, namely, sinkiangenorin F (1) and 8-O-acetyl sinkiangenorin F (2) were isolated from the seeds of Ferula sinkiangensis. The structures of the new compounds, including the relative stereochemistry and the absolute configuration were elucidated through extensive spectroscopic methods. The two compounds were tested against the K562, HeLa, and AGS human cancer cell lines and showed cytotoxic activities with 50% inhibitory concentration values between 27.1 and 62.7 μM.     

Toddanol and toddanone,two coumarins from Toddalia asiatica

Two new constituents isolated from the roots of Toddalia asiatica and designated as toddanol and toddanone have been characterized as 5,7-dimethoxy-6-(2-hydroxy-3-methylbut-3-enyl)coumarin (1) and 5,7-dimethoxy-6-(3-methyl-2-oxobutanyl)coumarin (3), respectively, by spectral analysis and interconversion experiments.     

Simple coumarins from two populations of Diosma acmaeophylla

Investigation of two collections of Diosma acmaeophylla afforded seven simple coumarins, three of which were common to both samples. The chemotaxon     

Coumarins in Eremocitrus glauca; Rutaceae; chemotaxonomy; coumarins; artifact; MS fragmentation.

2′,3′-Dihydroxydihydrosuberosin its acetonide derivative and 7-hydroxycoumarin has been isolated from the extracts of Eremocitrus glauca. The s