RESUMO
Two new triterpenes mayteneri A (1), mayteneri B (2), and seven known compounds (3-9) were isolated from stems of Maytenus hookeri Loes. The chemical structures of compounds 1 and 2 were established by 1D, 2D NMR, HRESIMS analysis, and calculating electronic circular dichroism (ECD). The structures of known compounds 3-9 were determined by comparison of their spectral with those reported. Compounds 4-7 showed significant inhibitory activity for NLRP3 inflammasome, with the IC50 values of 2.36-3.44 µM.
Assuntos
Maytenus , Ácido Oleanólico , Estrutura Molecular , Ácido Oleanólico/química , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Maytenus/química , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Caules de Planta/química , Animais , Camundongos , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidoresRESUMO
Three new coumarin derivatives named maytenucoums A-C (1-3), along with six known analogs (4-9), were isolated from the branches of Maytenus hookeri. Their structures were determined by comprehensive spectroscopic data analysis, including NMR and HR-ESIMS. In the preliminary assays, compound 4 showed cytotoxic activity against the A549, SK-Hep1 and HCT116 cells with IC50 values of 29.0, 28.6 and 54.4 µM, respectively.
RESUMO
In previous work, a series of bioactive natural products had been isolated from the plant endophytic Streptomyces sp. CS, which was isolated from Maytenus hookeri. To mine new active metabolites, we describe introducing an alien carbamoyltransferase (asm21) gene into the strain CS by conjugal transfer. As a result, three recombinatorial mutants named CS/asm21-1, CS/asm21-2 and CS/asm21-4 were successfully constructed. Three mutants and wild type CS were cultured on solid medium, and the extracts were detected and analyzed by liquid chromatography-mass spectrometry (LC-MS). The LC-MS profiles showed several unknown peaks that were present in the spectra of extracts of the CS/asm21-4 cultured on oatmeal solid medium. Then, three new naphthomycins O-Q (1-3), a new macrolide hookerolide (4) as well as nine known compounds were obtained from the solid cultured medium. Their structures were identified by spectra data. These new compounds showed moderate antimicrobial activities.