title: Cytotoxic tirucallane triterpenoids from the stem bark of Melia toosendan.
abstract: Three new tirucallane triterpenoids, 3β,16-dihydroxy-25-hydroperoxytirucalla-7,23(24)-dien-6-oxo acid (1), 3β,16β-hydroxytirucalla-7,24(25)-dien-21,23-olide (2), and 3β,16β-hydroxytirucalla-7,24(25)-dien-6-oxo-21,23-olide (3) were isolated from the 70% ethanol extract of the stem bark of Melia toosendan. Their structures were determined on the basis of 1D and 2D NMR (COSY, HMQC, HMBC and NOESY) analyses. The isolated compounds were evaluated in vitro for cytotoxic activities against A549, SK-OV-3, SK-MEL-2 and HCT15 tumor cell lines. Compounds 2 and 3 exhibited significant cytotoxic activities against the four tested cell lines with IC(50) values of 3.4-5.7 μg/mL and 3.2-5.0 μg/mL, respectively.
authors.affiliation: Department of Organic Chemistry, College of Pharmacy, Second Military Medical University, Shanghai 200433, China. qjzhao@smmu.edu.cn
authors.forename: Qingjie
authors.initials: Q
authors.lastname: Zhao
authors.forename: Yan
authors.initials: Y
authors.lastname: Song
authors.forename: Chuanwei
authors.initials: C
authors.lastname: Feng
authors.forename: Haisheng
authors.initials: H
authors.lastname: Chen
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage / Q000494:pharmacology*; D045744:Cell Line, Tumor; D006801:Humans; D020128:Inhibitory Concentration 50; D009682:Magnetic Resonance Spectroscopy; D031585:Melia / Q000737:chemistry*; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D024301:Plant Bark; D010936:Plant Extracts / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D018547:Plant Stems; D013729:Terpenes; D014315:Triterpenes / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: C580981:3beta,16-dihydroxy-25-hydroperoxytirucalla-7,23(24)-dien-6-oxo acid; C580980:3beta,16beta-hydroxytirucalla-7,24(25)-dien-21,23-olide; C580982:3beta,16beta-hydroxytirucalla-7,24(25)-dien-6-oxo-21,23-olide; D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D013729:Terpenes; D014315:Triterpenes; C514393:tirucallane