Non-taxane compounds from the bark of Taxus yunnanensis.

From the bark of Taxus yunnanensis, 15 non-taxane compounds were isolated. Through spectroscopic methods such as ID and 2D NMR and MS experiments, one of them was determined as a new abietane-type diterpenoid named taxayunnin (1). The other 14 known compounds were identified as taxamairin C (2), taxamairin A (3), 3beta-hydroxy-sandaracopimaric acid (4), (+)-3-hydroxy-isodrimenin (5), rubrosterone (6), ponasterone A (7), ecdysterone (8), 20-hydroxy-echysone-20,22-monoacetonide (9), 7-oxositosterol (10), stigmast-4-en-6beta-ol-3-one (11), 5alpha,6beta-dihydroxy-daucosterol (12), beta-sitosterol (13), daucosterol (14), 1-O-beta-D-glucopyranosyl-(2S, 3R, 4E, 8Z)-2-N-(2'-hydroxypalmitoy])-octadeca-sphinga-4,8-dienine (15), respectively. Compounds 4-6, 9-12 and 15 were isolated from Taxus plants for the first time.