New natural diterpene acids from Juniperus communis
作者:J. de Pascual Teresa、A.F. Barrero、L. Muriel、A. San Feliciano、M. Grande
DOI:10.1016/0031-9422(80)83074-3
日期:1980.1
Abstract Three new diterpeneacids have been isolated from the leaves of Juniperus communis and their structures, elucidated by spectroscopic methods, were identified as 7-oxo-13-epi- pimara-8,15-dien-18-oic acid, 7α-hydroxysandaracopimaric acid and (14 S)-14,15-dihydroxylabda- 8(17),13(16)-dien-19-oic acid. Biflavonyls, fatty acids and diterpenoids with known structures were also isolated.
Abstract13C NMR spectra of several hydroxy diterpene derivatives having a pimarane, isopimarane and (13S, 8α)rosane skeleton have been recorded. The most significant effects caused by the introduction of hydroxyl groups in such a skeleton are demonstrated. The magnitudes of the γ‐ and δ‐effects are large enough to allow their use in sterochemical assignments.