Digital.CSIC > Ciencia y Tecnologías Químicas > Centro de Química Orgánica 'Manuel Lora-Tamayo' (CENQUIOR) > (CENQUIOR) Artículos >





Closed Access item H-1 and C-13 NMR spectral assignments and conformational analysis of 14 19-nor-neoclerodane diterpenoids

Authors:Rodríguez, Benjamín
Jimeno, M. Luisa
Keywords:NMR, 1HNMR, 13C NMR, diterpenoids, 19-nor-neoclerodanes, conformational analysis, molecular modelling, structure correction, 2-hydroxyteucvidin, 19-nor-neoclerodane-18-al derivative
Issue Date:2004
Publisher:John Wiley & Sons
Citation:Magnetic Resonance in Chemistry 42 : 605-616 (2004)
Abstract:Unambiguous and complete assignments of 1H and 13C NMR chemical shifts for 14 19-nor-neoclerodane diterpenoids, nine of them isolated from natural sources and five other synthetic derivatives, are presented. The assignments are based on 2D shift-correlated (1H,1H-COSY, 1H,13C-gHSQC and 1H,13C-gHMBC) and NOE experiments. The conformations of rings A and B of these compounds are supported by the 3J(H,H) values and they agreewith the low-energy conformations obtained by semi-empirical calculations. Moreover, the data obtained in thiswork for 2-acetoxyteucvidin and a semisynthetic 18-aldehyde derivative indicate that the configuration at C-2 of the former and at C-10 of the latter must be reversed with respect to those reported previously.
Publisher version (URL):http://dx.doi.org/10.1002/mrc.1384
Appears in Collections:(CENQUIOR) Artículos

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.