ABSTRACT
The organic extract of the plant Maclura tinctoria exhibited moderate anti-HIV activity. Seven prenylated phenolic derivatives were isolated from the active fractions and characterized by spectroanalytical methods. New compounds macluraxanthone B (1), macluraxanthone C (2), and dihydrocudraflavone B (8) were identified.
Subject(s)
Anti-HIV Agents/isolation & purification , Anti-HIV Agents/pharmacology , Flavonoids/isolation & purification , Flavonoids/pharmacology , Plants, Medicinal/chemistry , Xanthenes/isolation & purification , Xanthines/isolation & purification , Xanthines/pharmacology , Xanthones , Chloroform , Chromatography, Gel , Chromatography, High Pressure Liquid , HIV/drug effects , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Plant Extracts/analysis , Spectrophotometry, Ultraviolet , Xanthenes/pharmacologyABSTRACT
A new polyisoprenylated phloroglucinol derivative has been isolated from the twigs of Marila laxiflora and characterized on the basis of 1D and 2D NMR spectra. Laxifloranone (1) shows moderate inhibition of the cytopathic effects of in vitro HIV infection.
Subject(s)
Anti-HIV Agents/isolation & purification , HIV Infections/drug therapy , Phloroglucinol/analogs & derivatives , Plants, Medicinal/chemistry , Anti-HIV Agents/chemistry , Anti-HIV Agents/pharmacology , Cell Line , Cytopathogenic Effect, Viral/drug effects , Humans , Magnetic Resonance Spectroscopy , Phloroglucinol/chemistry , Phloroglucinol/isolation & purification , Phloroglucinol/pharmacology , Spectrometry, Mass, Fast Atom BombardmentABSTRACT
Two novel natural products, lanneaquinol (1) and 2'(R)-hydroxylanneaquinol (2), were isolated from the organic extract of the plant Lannea welwitschii (Hiern) Engl. Their structures were solved by spectroanalytical methods and confirmed by comparison to synthetic models. The absolute configuration of 2 was determined by the modified Mosher method. Both compounds exhibited modest cytotoxicity against the NCI panel of 60 human tumor cell lines. The structures of two isomeric 4,5-dihydroxy-5-alkyl-2-cyclohexenones (7 and 8), which appear to be biogenetic precursors of 1 and 2, were also elucidated.
Subject(s)
Antineoplastic Agents, Phytogenic/isolation & purification , Hydroquinones/isolation & purification , Alkylation , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Chromatography, Ion Exchange , Humans , Hydroquinones/chemistry , Hydroquinones/pharmacology , Magnetic Resonance Spectroscopy , Spectrometry, Mass, Fast Atom Bombardment , Stereoisomerism , Tumor Cells, CulturedABSTRACT
Stypoldione, a marine natural product that possesses an o-quinone functional group, has been shown to inhibit a variety of biological processes including cell division. We found that stypoldione binds covalently to sulfhydryl groups of thiol-containing compounds via addition of sulfur to the C-4' position of the quinone ring. We examined the ability of stypoldione to add to sulfhydryl groups of a number of thiol-containing substances, including glutathione, thiophenol, beta-mercaptoethanol, and the protein tubulin. We suggest that the biological actions of stypoldione may be caused by the addition of this compound to thiol groups of biological molecules.
Subject(s)
Marine Toxins/pharmacology , Quinones/pharmacology , Sulfhydryl Compounds/metabolism , Cell Division/drug effects , Colchicine/metabolism , Microtubules/drug effects , Quinones/metabolism , Tubulin/metabolismABSTRACT
Two toxins, latrunculins A and B, which contain a new class of 16- and 14-membered marine macrolides attached to the rare 2-thiazolidinone moiety, were purified recently from the Red Sea sponge Latrunculia magnifica. The effects of these toxins on cultured mouse neuroblastoma and fibroblast cells have been evaluated. In both types of cells, submicromolar toxin concentrations rapidly induce striking changes in cell morphology that are reversible upon removal of the toxin. Immunofluorescence studies with antibodies specific for cytoskeletal proteins reveal that the toxins cause major alterations in the organization of microfilaments without obvious effects on the organization of the microtubular system.
