Structural reassignment of epierythratidine, an alkaloid from erythrinafusca, based on NMR studies and computational methods

García-Beltrán, OlimpoSoto-Delgado, JorgeIturriaga-Vásquez, PatricioAreche, CarlosCassels, Bruce K.2013-10-222016-05-242013-10-222016-05-242012Journal of the Chilean Chemical Society, Vol. 57, N° 3, pp. 1323-1327, 2012.ISSN: 0717-9707http://dx.doi.org/10.4067/S0717-97072012000300027http://repositorio.unab.cl/xmlui/handle/ria/1951Indexación: Web of Science; ScieloThe diene Erythrina alkaloids erysotrine (1), erysodine (2), erythraline (3), erytharbine (4), and erysotrine N-oxide (5), plus the hydroxylated dihydro derivative of 1, epierythratidine (6) were isolated from seeds of Erythrina fusca Lour., and their 1H and 13C NMR spectra were completely assigned using 2D experiments (H-H COSY, HMQC, HMBC and H-H NOESY). Our assignments for 1-5 agree well with the literature, but the present work shows that the published interpretation of the spectra of 6 must be revised. A combined study based on NMR data and quantum-mechanical calculations using DFT/GIAO indicate that 6 is the correct structure of epierythratidine.enErythrina alkaloidsErythrina fuscaEpierythratidine1H NMR13C NMR2D NMRGIAO/DFT methodsStructural reassignment of epierythratidine, an alkaloid from erythrinafusca, based on NMR studies and computational methodsArtículo© 2013 Sociedad Chilena de Química