Vladimuliecins A and B: cytotoxic pentacyclic pregnanols from Vladimiria muliensis.
Two new steroids, vladimuliecins A (1) and B (2), were isolated by bioassay-guided fractionation from the rhizome of Vladimiria muliensis. Compounds 1 and 2 are the first examples possessing a pentacyclic 3alpha,5alpha-cyclopregnane-type framework. The structures of vladimuliecins A (1) and B (2) and their deacetylated derivative (3) were determined on the basis of IR, MS, 1D NMR, 2D NMR, and X-ray data analyses. The absolute configuration of the 10 stereogenic centers of compounds 1 and 2 was determined to be 3R,5R,6R,8S,9R,10R,13R,14R,17S,20R by means of auxiliary chiral MTPA derivatives and optical rotation calculation. A probable biosynthesis pathway to 1 and 2 is also proposed and discussed. In addition, the cytotoxicity of compounds 1, 2, and 3 was evaluated against selected cancer cell lines, including human leukemia cell (HL-60), human hepatoma cell (SMMC-7721), and human cervical carcinoma cell (HeLa) lines.
Chen
Jian-Jun
JJ
State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, People's Republic of China.
Li
Zheng-Ming
ZM
Gao
Kun
K
Chang
Jin
J
Yao
Xiao-Jun
XJ
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D018922:HL-60 Cells; D006367:HeLa Cells; D006801:Humans; D020128:Inhibitory Concentration 50; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010946:Plants, Medicinal / Q000737:chemistry*; D011278:Pregnanes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D027343:Rhizome / Q000737:chemistry; D013237:Stereoisomerism
D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D011278:Pregnanes; C542028:vladimuliecin A; C542029:vladimuliecin B