title: New bioactive clerodane diterpenoids from the roots of Casearia membranacea.
abstract: Bioassay-guided fractionation of the acetone extract of the roots of Casearia membranacea furnished three new clerodane diterpenes, caseamembrins S-U (1-3) and the known caseamembrin Q (4). Their structures were established by extensive spectroscopic analyses, especially 2D-NMR. Compounds 1-4 were tested against human tumor cells, including HeLa (cervical epitheloid carcinoma), DLD-1 (colon carcinoma), Daoy (medulloblastoma), and KB (oral epidermoid carcinoma) cell lines. Caseamembrin T (2) exhibited the most potent activity against Daoy cells (ED(50)=10 ng/ml), superior to that of the standard drug mitomycin.
authors.affiliation: Center of General Education, Tzu-Hui Institute of Technology, Kaohsiung, Taiwan, Republic of China.
authors.forename: Ching-Yu
authors.initials: CY
authors.lastname: Chen
authors.forename: Yuan-Bin
authors.initials: YB
authors.lastname: Cheng
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: Jih-Hwa
authors.initials: JH
authors.lastname: Guh
authors.forename: Ashraf Taha
authors.initials: AT
authors.lastname: Khalil
authors.forename: Ya-Ching
authors.initials: YC
authors.lastname: Shen
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D037821:Casearia / Q000737:chemistry*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D045785:Diterpenes, Clerodane / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006367:HeLa Cells; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D008968:Molecular Conformation; D018517:Plant Roots / Q000737:chemistry*; D012015:Reference Standards; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D000970:Antineoplastic Agents; D045785:Diterpenes, Clerodane