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The petroleum ether and acetone extracts of the aerial parts of Sideritis arguta afforded two new and six known diterpenoids with the ent-kaurane skeleton. The structures of the new diterpenoids were determined as ent-7alpha,18-diacetoxy-16beta-hydroxykaurane (diacetyldistanol) (1) and ent-7alpha-acetoxy,15alpha,18-dihydroxykaur-16-ene (15-epi-eubol) (2) by spectroscopic data interpretation. Antioxidant potential was investigated for the ent-kauranes and the plant extracts by three methods (beta-carotene bleaching, free-radical scavenging, and superoxide-anion scavenging activity). Acetylcholinesterase and butyrylcholinesterase inhibitory activity were also evaluated, and the ent-kauranes eubol (3), sideroxol (5), and 7-epi-candicandiol (6) exhibited moderate butyrylcholinesterase inhibitory activity.

Salvia species are important medicinal and culinary plants, and they have been the subject of numerous chemical and biological studies. The bioactive triterpenoids of Salvia species, reported in the literature to date, are reviewed. About 200 triterpenoids, almost 80 of which are new, isolated, and characterized from about 100 Salvia species, are presented herein. In addition to the diverse biological activities of the pure triterpenoids, studies on biological activity of extracts of Salvia species are also described.

A beta-carboline-, a tryptamine-, and two phenylethylamine-derived alkaloids and three known aromatic compounds were isolated from the aerial parts and roots of Cyathobasis fruticulosa (Bunge) Aellen, and their structures were elucidated by spectroscopic techniques. The one new alkaloid, N-methyl-N-formyl-4-hydroxy-beta-phenylethylamine (1), showed marginal antifungal activity.

The three new triterpenes (1-3) and five known triterpenes and a sterol were isolated from the acetone extract of a Turkish collection of Salvia kronenburgii. The structures of the new triterpenes were established as 1beta,2alpha-dihydroxy-3beta-acetoxy-11-oxours-12-ene (1), 2alpha,20beta-dihydroxy-3beta-acetoxyurs-9(11),12-diene (2), and 1beta,2alpha-dihydroxy-3beta-acetoxyurs-9(11),12-diene (3) on the basis of spectral analyses, including 1D and 2D NMR and mass spectroscopy. It is probable that compounds 2 and 3 are artifacts from dehydration of the corresponding allylic alcohols. 1beta,2alpha,3beta,11alpha-Tetrahydroxyurs-12-ene (5), the most abundant compound in the extract, was found to be highly cytotoxic to renal, non-small cell lung, and breast cancer cell lines.

The acetone extract of Nepeta caesarea yielded four new nepetalic acid derivatives, 3'alpha-[beta-sitosteryl-3beta-oxy]dihydronepetalactone (1), 3'beta-[5alpha-stigmast-7-ene-3beta-oxy]dihydronepetalact one (2), 3'alpha-[olean-12-ene-28-oyl-3beta-oxy]dihydronepetalactone (3), and 3'alpha-[lup-20(29)-ene-28-ol-3beta-oxy]dihydronepetalactone (4). The structures were elucidated by NMR and MS techniques.