Some progress on the chemistry of natural bioactive terpenoids from Chinese medicinal plants

Abstract

(1) Pseudolaric acids--Novel diterpenes, Pseudolaric acid A, B, C and D were isolated from Pseudolarix kaempferi Gorden (pinaceae). Their structures were assigned by spectroscopic data and chemical correlations. In the continuous studies, the absolute configurations, the conformations in the solutions, the fragmentation mechanisms of MS and assignments of all NMR spectral signals were also reported. They showed the antifungal and cytotoxic activities. (2)--Daphnane diterpenes--In the further studies on the plants of Thymelaeaceae, besides 10 known diterpenes, 16 new daphnane diterpenes were isolated from Daphne genkwa, D. tangutica, D. giraldii, Wikstroemie chamaedaphne. They showed the antifertilities activities. (3) Tripterygium diterpenes--14 new diterpenes were isolated from Triperygium wilfordii, T. regeli and T. hypoglaucum. Some of them showed the antitumour activities. The CD spectra showed that A/B ring of all compounds have trans configuration as same as tripdiolide and triptolide determined by X-ray diffraction. (4) Pregnane glycosides from Marsdenia koi--Two new pregnane glycosides marsdenikoiside A and marddenikoiside B which can terminate the early pregnancy were isolated from Marsdeia koi. Their structures were elucidated by hydrolysis and spectroscopic methods.

PIP: Bioactive terpenes were isolated from the following plant species: 1) Pseudolaric acids: The active compounds of novel diterpenes, Pseudolaric acid A, B, C, and D, were isolated from Pseudolarix kaempferi Gordon (pinaceae). Their structures were determined by spectroscopic data and chemical correlations. In continuous studies, absolute configurations, confirmation in solutions, fragmentation mechanisms of MS, and assignments of all nuclear magnetic resonance (NMR) spectral signals were also reported. They showed antifungal and cytotoxic activities. Pseudolaric acid A 1 and B 2 showed antifungal activities. Recently, pseudolaric acid B was established as a general cytotoxic agent against P-388 lymphocytic leukemia, KB carcinoma of the nasopharynx, HT-1080 fibrosarcoma, H00 578T breast cancer, human melanoma, human lung cancer, and human colon cancer cell lines. 2) Daphnane diterpenes: In further studies on the plants of Thymelaeaceae, besides 10 known diterpenes, 16 new daphnane diterpenes were isolated from Daphne genkwa, D. tangutica, D. giraldii, Wikstroemie chamaedaphne that showed antifertility activities. In continuous studies, besides 6 known compounds, 17 new daphnane diterpenes were isolated. 3) Tripterygium diterpenes: 14 new diterpenes were isolated from Tripterygium wilfordii, T. regeli and T. hypoglaucum. Tripterygium wilfordii has been used as an anticancer drug, male contraceptive, and immunedepressant in Chinese folk medicine for a long time. Some of them showed antitumor activities. The CD spectra showed that A/B ring of all diterpenes had the same transconfiguration as tripdiolide and triptolide as determined by X-ray diffraction. In 1972 triptolide, tripdiolide and triptonide were isolated with significant anti-tumor activities. Celastrol demonstrated immunodepressive activities. In addition to 10 known triterpenes, 15 new diterpenes were isolated from the plants of Tripterygium by silica gel chromatography. 4) Pregnane glycosides from Marsdenia koi: Two new pregnane glycosides, marsdenikoiside A and marsdenikoiside B, which can terminate early pregnancy were isolated from Marsdenia koi. Their structures were elucidated by hydrolysis and spectroscopic methods.