title: Symmetric dimers of ent-kaurane diterpenoids with cytotoxic activity from Croton tonkinensis.
abstract: Breast cancer is the most common malignant tumor in women these days accounting for approximately 24% of all cancer. During our screening program searching for cytotoxic materials from natural products, two new symmetric dimers of ent-kaurane diterpenoid, crotonkinensins C (1) and D (2), with connectivity at C-17 were isolated from the leaves of the Vietnamese endemic medicinal plant Croton tonkinensis. Their structures were determined on the basis of physicochemical and spectroscopic data. Compound 2 showed a potent cytotoxic activity against MCF-7, tamoxifen-resistant MCF-7 (MCF-7/TAMR), adriamycin-resistant MCF-7 (MCF-7/ADR), and MDA-MB-231 breast cancer cell lines.
authors.affiliation: Vietnam National Institute of Medicinal Materials, 3B Quangtrung, Hoankiem, Hanoi, Viet Nam.
authors.forename: Phuong Thien
authors.initials: PT
authors.lastname: Thuong
authors.forename: Thi Hong Minh
authors.initials: TH
authors.lastname: Pham
authors.forename: Thi Van Thu
authors.initials: TV
authors.lastname: Le
authors.forename: Trong Tuan
authors.initials: TT
authors.lastname: Dao
authors.forename: Thai Trung
authors.initials: TT
authors.lastname: Dang
authors.forename: Quyet Tien
authors.initials: QT
authors.lastname: Nguyen
authors.forename: Won Keun
authors.initials: WK
authors.lastname: Oh
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D029802:Croton / Q000737:chemistry*; D019281:Dimerization; D045786:Diterpenes, Kaurane / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D005260:Female; D006801:Humans; D015394:Molecular Structure; D013329:Structure-Activity Relationship
chemical_list: D000970:Antineoplastic Agents; D045786:Diterpenes, Kaurane