RESUMO
Two new triterpenes cycloartane-type, named 24-methylencycloartan-12-oxo-3ß,22α-diol and trichiliol, were isolated from the leaves of Trichilia casaretti C. DC. together with three known triterpenes24-methylencycloart-3ß,22-diol, 22,25-dihydrocycloart-23(E)-en-3ß-ol, and 22(R)-hydroxycycloart-24-en-3-ol. These compounds were characterized on the basis of their spectral data, mainly 1D (¹H and 13C) and 2D NMR (¹H-¹H-COSY, ¹H-¹H-NOESY, HMQC, HSQC, and HMBC), and mass spectra (EI-MS and HR-ESI-MS), also involving comparison with data from the literature.
Assuntos
Meliaceae/química , Extratos Vegetais/química , Folhas de Planta/química , Triterpenos/química , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
The genus Psychotria (Rubiaceae) comprises more than 2000 species, mainly found in tropical and subtropical forests. Several studies have been conducted concerning their chemical compositions, showing that this genus is a potential source of alkaloids. At least 70 indole alkaloids have been identified from this genus so far. This review aimed to compile 13C-NMR data of alkaloids isolated from the genus Psychotria as well as describe the main spectral features of different skeletons.