ABSTRACT
Bioassay-guided fractionation of the MeOH and EtOAc fractions of extracts of two lianas collected in Suriname has led to the isolation of five new diterpenoids, humirianthone 1, 1-hydroxy-humirianthone 2, 15R-humirianthol 3, patagonol 4, and patagonal 5, and the five known diterpenoids, humirianthol 7, annonalide 8, acrenol 9, icacinol 10, and the oxidized annonalide 11. All 10 diterpenoids showed cytotoxic activity against the A2780 human ovarian cancer cell line, and compounds 1, 3, 8, and 9 also showed activity against phytopathogenic fungi.
Subject(s)
Diterpenes/isolation & purification , Diterpenes/toxicity , Plants, Medicinal/chemistry , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Antifungal Agents/toxicity , Cell Line, Tumor , Cell Proliferation/drug effects , Diterpenes/chemistry , Diterpenes/pharmacology , Fungi/drug effects , Fungi/physiology , Humans , Inhibitory Concentration 50 , Magnetic Resonance Spectroscopy , Rain , Suriname , TreesABSTRACT
Bioassay-guided fractionation of an EtOAc extract of the leaves of Melampodium camphoratum using an assay for inhibitors of the degradation of hemin resulted in the isolation of six new eudesmane sesquiterpenes (1-6) and the known 6-epi-beta-verbesinol coumarate (7). The structures of compounds 1-6 were established as 6alpha-(4'-O-methyl-7'E-coumaryloxy)eudesm-4(14)-ene (1), 6alpha-({4'-O-stearyl}-7'E-coumaryloxy)eudesm-4(14)-ene (2), 6alpha-({4'-O-palmityl}-7'E-coumaryloxy)eudesm-4(14)-ene (3), 6alpha-({4'-O-[9' 'Z-hexadecenoyl]}-7'E-coumaryloxy)eudesm-4(14)-ene (4), 6alpha-(7'Z-coumaryloxy)eudesm-4(14)-ene (5), and 6alpha-({4'-acetoxy}-7'Z-coumaryloxy)eudesm-4(14)-ene (6). Compounds 1-4 showed weak activity in the hemin degradation assay, while compounds 5-7 were inactive.
Subject(s)
Antimalarials/isolation & purification , Asteraceae/chemistry , Hemin/metabolism , Plants, Medicinal/chemistry , Sesquiterpenes, Eudesmane/isolation & purification , Animals , Antimalarials/chemistry , Antimalarials/pharmacology , Inhibitory Concentration 50 , Molecular Structure , Plant Leaves/chemistry , Plasmodium falciparum/drug effects , Sesquiterpenes, Eudesmane/chemistry , Sesquiterpenes, Eudesmane/pharmacology , Stereoisomerism , SurinameABSTRACT
Bioactivity-directed fractionation of a methanol extract of Hymenaea courbaril afforded the three new diterpenoids (13R)-13-hydroxy-1(10),14-ent-halimadien-18-oic acid (1), (2S,13R)-2,13-dihydroxy-1(10),14-ent-halimadien-18-oic acid (2), and (13R)-2-oxo-13-hydroxy-1(10),14-ent-halimadien-18-oic acid (3). The configurations of these compounds were determined from X-ray crystallography of 1, circular dichroism of 2 and 3, and spectral studies of prepared derivatives. Compound 1 exhibited weak cytotoxicity toward the 1138 mutant yeast strain and the A2780 human ovarian cancer cell line.
