title: Two novel alkaloids with a unique fused hexacyclic skeleton from Daphniphyllum subverticillatum.
abstract: Two novel major alkaloids, deoxycalyciphylline B (1) and deoxyisocalyciphylline B (2) with a unique fused hexacyclic skeleton, together with a quite recently reported alkaloid calyciphylline B (3), were isolated from the stem of Daphniphyllum subverticillatum. Their structures were established by spectral methods and chemical evidence, especially 2D NMR techniques. The structure of 1 was further confirmed by a single-crystal X-ray diffraction determination.
authors.affiliation: State Key Laboratory of Drug Research, Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 555 Zu Chong Zhi Road, Zhangjiang Hi-Tech Park, Shanghai 201203, P. R. China.
authors.forename: Sheng-Ping
authors.initials: SP
authors.lastname: Yang
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Yue
mesh_terms: D000470:Alkaloids / Q000302:isolation & purification*; D002236:Carbohydrate Conformation; D018360:Crystallography, X-Ray; D006576:Heterocyclic Compounds, 4 or More Rings / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D018547:Plant Stems / Q000737:chemistry; D031995:Saxifragaceae / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D006576:Heterocyclic Compounds, 4 or More Rings; C482084:deoxycalyciphylline B; C482083:deoxyisocalyciphylline B