ABSTRACT
A methanol extract of Combretum erythrophyllum showed inhibitory bioactivities in a yeast-based microtiter assay for DNA-damaging agents. Bioassay-guided fractionation of this extract yielded two known bioactive compounds, combretastatin A-1 and (-)-combretastatin, and two new bioactive glucosides, combretastatin A-1 2'-beta-D-glucoside (1) and combretastatin B-1 2'-beta-D-glucoside (2). The structures of the new compounds were assigned by (1)H and (13)C NMR, DEPT, HMQC, and HMBC spectra.
Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Bibenzyls/isolation & purification , DNA Damage/drug effects , Plants, Medicinal/chemistry , Stilbenes/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Bibenzyls/toxicity , Carbohydrate Sequence , DNA Repair/drug effects , Drug Screening Assays, Antitumor , Glycosides/isolation & purification , Glycosides/pharmacology , Humans , Magnetic Resonance Spectroscopy , Mass Spectrometry , Molecular Sequence Data , Plant Extracts/chemistry , Plant Extracts/pharmacology , South Africa , Spectrophotometry, Ultraviolet , Stilbenes/toxicity , Tumor Cells, Cultured , WoodABSTRACT
The hexane extract of the bark of Entandrophragma delevoyi has yielded a novel tetranortriterpenoid, delevoyin C. This compound contains a cyclobutanyl ring incorporating C-19 and a cycloheptanyl ring C including C-30. Gedunin and 11beta-Acetoxygedunin were isolated from the hexane extract of the wood.
Subject(s)
Trees/chemistry , Triterpenes/isolation & purification , Hexanes , Magnetic Resonance Spectroscopy , Plant Extracts/chemistry , Triterpenes/chemistryABSTRACT
The stem bark of Astrotrichilia voamatata (Meliaceae) has yielded the novel limonoids voamatins C and D. These compounds represent a new type of pentanortriterpenoid and are unique in containing a ring A cyclic ether.
