title: Kleinhospitines A-D, new cycloartane triterpenoid alkaloids from Kleinhovia hospita.
abstract: Kleinhospitines A-D, four unprecedented cycloartane triterpenoid alkaloids possessing a spiro α,β-unsaturated γ-lactamlactone side chain, were isolated as two mixtures of C-23 epimers from Kleinhovia hospita. Kleinhospitines C and D represent the first examples of naturally occurring cycloartane triterpenoids with a 9α,10α-cyclopropyl ring. The structures and absolute configurations were determined on the basis of spectroscopic analyses and comprehensive quantum chemical calculations. The two mixtures showed hepatoprotective activity against H2O2-induced oxidative damages on primary cultured rat hepatocytes with EC50 values of 167.0 and 126.5 μM.
authors.affiliation: College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, PR China.
authors.forename: Chang-Xin
authors.initials: CX
authors.lastname: Zhou
authors.forename: Li
authors.initials: L
authors.lastname: Zou
authors.forename: Li-She
authors.initials: LS
authors.lastname: Gan
authors.forename: Yue-Lan
authors.initials: YL
authors.lastname: Cao
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology*; D000818:Animals; D022781:Hepatocytes / Q000737:chemistry* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011789:Quantum Theory; D051381:Rats; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D014315:Triterpenes; C584717:kleinhospitine C; C584718:kleinhospitine D; C085352:cycloartane; D006861:Hydrogen Peroxide