若干非天然产C_(19)-二萜生物碱的结构及其核磁共振谱的研究

STUDIES ON THE STRUCTURES AND NMR SPECTRA OF SOME NONNATURALLY-OCCURING C_(19)-DITERPENOID ALKALOIDS

根据光谱分析确定了16个非天然产二萜生物碱1-16的结构。指定了化合物1-9、12-16的氢谱和1-10、12-14的碳谱。有趣的是N-氧化物8在乙酰氯(-5℃,2日)作用下生成去氮乙基化合物15。讨论了化合物12-16形成的可能反应机理。

Sixteen nonnatuaturall-y-occuring diterpenoid alkaloids 1-16 wereobtained in our studies on the diterpenoidalkaloids. Their structues were establishedon the basis of spectral analysis. The che-mical shifts of protons for 1-9, 12-16 andcarbon-13 for 1-10, 12-14, 16 were assign-ed. It is worth to note that N-oxide 8 re-acts with acetyl chloride to form N-dese-thyl compound 15 under a mild condition(-5℃, 2 days). In addition, mechanismsof formation for 12-16 were also discuss-ed.