title: Cytotoxic clerodane diterpenoids from Casearia membranacea.
abstract: Bioassay-guided fractionation of the EtOAc extract of Casearia membranacea leaves and twigs afforded three new clerodane diterpenes, caseamembrins M-O (1-3), and the known rel-(2S,5R,6R,8S,9S,10R,18S,19R)-2-(2-methylbutyryloxy)-6-hydroxy-18,19-di-O-acetyl-18,19-epoxycleroda-3,13(16),14-triene (4) and caseamembrin D (5). The structures of 1-3, including the relative configurations, were established by extensive NMR spectroscopic analyses. The cytotoxic activities of the isolated diterpenoids against human oral epidermoid (KB), medulla (Med), and colon (DLD-1) cancer cell lines were evaluated.
authors.affiliation: Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung 804, Taiwan, Republic of China. ycshen@mail.nsysu.edu.tw
authors.forename: Ya-Ching
authors.initials: YC
authors.lastname: Shen
authors.forename: Yuan-Bin
authors.initials: YB
authors.lastname: Cheng
authors.forename: Atallah F
authors.initials: AF
authors.lastname: Ahmed
authors.forename: Cheng Lin
authors.initials: CL
authors.lastname: Lee
authors.forename: Shun-Ying
authors.initials: SY
authors.lastname: Chen
authors.forename: Ching-Te
authors.initials: CT
authors.lastname: Chien
authors.forename: Yao-Haur
authors.initials: YH
authors.lastname: Kuo
authors.forename: Guo-Lin
authors.initials: GL
authors.lastname: Tzeng
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D037821:Casearia / Q000737:chemistry*; D045785:Diterpenes, Clerodane / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D013624:Taiwan; D014407:Tumor Cells, Cultured
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D045785:Diterpenes, Clerodane; C506493:caseamembrin M; C506494:caseamembrin N; C506495:caseamembrin O