RESUMO
Continuation of a previous study on Renealmia alpinia resulted in the isolation of the new labdane diterpenoid 3, together with two known diterpenoids. The structure of the new diterpenoid was determined by a combination of NMR techniques and HRFABMS.
Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Diterpenos/isolamento & purificação , Zingiberales/química , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Saccharomyces cerevisiae/efeitos dos fármacos , Espectrometria de Massas de Bombardeamento Rápido de Átomos , SurinameRESUMO
Continuation of a previous study on Renealmia alpinia resulted in the isolation of the new labdane diterpenoid 3, together with two known diterpenoids. The structure of the new diterpenoid was determined by a combination of NMR techniques and HRFABMS. (AU)
Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Diterpenos/isolamento & purificação , Zingiberales/química , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Saccharomyces cerevisiae/efeitos dos fármacos , Espectrometria de Massas de Bombardeamento Rápido de Átomos , SurinameRESUMO
Bioassay-guided fractionation of an extract of a mixture of Microphilis guyanensis and Genipa americanacollected in the rainforest of Suriname yielded the known alkaloid cryptolepine (2) as the major active compound in a yeast bioassay for potential DNA-damaging agents; the same compound was later reisolated from M. guyanensis. The structure of cryptolepine was identified unambiguously by spectral data and by its total synthesis. Several cryptolepine derivatives (3-29, 32-41) were synthesized based on modifications of the C-2, N-5, N-10, and C-11 positions. Two cryptolepine dimers (30, 31) were also prepared. The structure modifications did not result in compounds with a higher potency than the parent compound cryptolepine in the yeast assay system, although some derivatives did show significant activity. Selected compounds (6, 7, 17, 22, 23, 26, and 27) were also tested for cytotoxicity in mammalian cell culture, and two compounds showed significant cytotoxic activity.
Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Indóis , Plantas Medicinais/química , Quinolinas , Alcaloides/síntese química , Alcaloides/farmacologia , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Dano ao DNA , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Alcaloides Indólicos , Testes de Sensibilidade Microbiana , Saccharomyces cerevisiae/efeitos dos fármacos , Suriname , Células Tumorais CultivadasRESUMO
Bioassay-guided fractionation of Eschweilera coriacea collected in the lowland wet forest of Suriname yielded the new but only weakly active ellagic acid derivative eschweilenol A (1) and the two new but inactive ellagic acid derivatives eschweilenol B (2) and eschweilenol C (3). The four known compounds, sucrose, ellagic acid, 3-O-galloylepigallocatechin, and epigallocatechin, were also isolated. The structures of the three new compounds were determined by spectrometric methods, primarily from the HMQC, HMBC, NOESY, and ROESY NMR techniques, and chemical methods, including methylation and triethylsilylation. The location of a hydroxyl group in one ellagic acid derivative was determined by a new technique involving an NOE correlation of the protons of a triethylsilyl derivative with a proton on a neighboring aromatic ring.