【摘 要】
：
Tabernaesine J(1),an unprecedented vincamine-type indole alkaloid with 6/5/6/6/6/5/5 heptacyclic-ring system,as well as one new biogenetically related vincamine-type indole alkaloid(2),were isolated from leaves of Tabernaemontana pachysiphon.Their structu
【机 构】
：
State Key Laboratory of Phytochemistry and Plant Resources in West China,Kunming Institute of Botany
论文部分内容阅读
Tabernaesine J(1),an unprecedented vincamine-type indole alkaloid with 6/5/6/6/6/5/5 heptacyclic-ring system,as well as one new biogenetically related vincamine-type indole alkaloid(2),were isolated from leaves of Tabernaemontana pachysiphon.Their structures were established by a combination of HRESIMS,NMR,single crystal X-ray diffraction,and ECD calculation.The unprecedented pen-ta-lactone ring in tabernaesine J(1)was postulated to be derived from acetyl-CoA enolate anion.Alkaloid 2 combined with fluconazole has the potential to overcome fluconazole resistance in Candida albicans.
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