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 1D 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), 3-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-6-ol-3-one (11), 5α,6-dihydroxy-daucosterol (12), -sitosterol (13), daucosterol (14), 1-O--d-glucopyranosyl-(2S, 3R, 4E, 8Z)-2-N-(2′-hydroxypalmitoyl)-octadeca-sphinga-4,8-dienine (15), respectively. Compounds 4-6, 9-12 and 15 were isolated from Taxus plants for the first time.