stigmasterol and Leukemia-P388

Two new isomeric acylated oleanane-type triterpenoids along with three known compounds were isolated from the MeOH extract of the dried fruits of Barringtonia racemosa. On the basis of spectroscopic methods, with special emphasis on 1D and 2D NMR techniques as well as chemical methods, the structures were characterized as racemosol A (1) [22alpha-acetoxy-3beta,15alpha,16alpha,21beta-tetrahydroxy-28-(2-methylbutyryl)olean-12-ene] and isoracemosol A (2) [21beta-acetoxy-3beta,15alpha,16alpha,28-tetrahydroxy-22alpha-(2-methylbutyryl)olean-12-ene]. The isolated compounds (1-5) were not active against HeLa and P388 D1 carcinoma cell lines.

Topics: Animals; Barringtonia; Drug Screening Assays, Antitumor; HeLa Cells; Humans; India; Leukemia P388; Mice; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Oleanolic Acid; Stereoisomerism

Bioassay (P388 lymphocytic leukemia cell line and human cancer cell lines)-guided separation of an extract prepared from the stem bark and twigs of the previously uninvestigated Ruprechtia tangarana led to the isolation of a new isocarbostyril designated ruprechstyril (1), secalonic acid A (2), 2'-O-methylevernic acid (3), 3,3',4-tri-O-methylflavellagic acid (4), lichexanthone (5), methyl asterrate (6), and 3beta,22E,24S-stigmasta-5,22-dien-3-ol (7). Only secalonic acid A exhibited cancer cell and microbial growth inhibition. The structure of ruprechstyril (1) was determined by HRMS and 1D and 2D NMR spectra and confirmed by single-crystal X-ray analysis. The structures and absolute stereochemistry of five of the other compounds were also established by X-ray crystal structure determination.

Topics: Animals; Antineoplastic Agents, Phytogenic; Crystallography, X-Ray; Drug Screening Assays, Antitumor; Humans; Hydroxyquinolines; Leukemia P388; Molecular Conformation; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Peru; Plants, Medicinal; Polygonaceae; Stereoisomerism