Cassane diterpenes from Caesalpinia platyloba.
Published on Dec 1, 2013in Phytochemistry3.044
· DOI :10.1016/J.PHYTOCHEM.2013.09.028
Mario A. Gómez-Hurtado8
(UMSNH: Universidad Michoacana de San Nicolás de Hidalgo), Fany E. Álvarez-Esquivel1
Estimated H-index: 8
(UMSNH: Universidad Michoacana de San Nicolás de Hidalgo)+ 8 AuthorsRosa E. del Río12
Estimated H-index: 1
(UMSNH: Universidad Michoacana de San Nicolás de Hidalgo)
Estimated H-index: 12
Abstract The dichloromethane extract from the leaves of Caesalpinia platyloba provided cassane diterpenes whose structures were determined as (−)-(5S,6R,8S,9S,10R,14R)-6-acetoxyvouacapane (1), (−)-(5S,6R,8S,9S,10R,12Z,14R)-6-acetoxycassa-12,15-diene (3), and (−)-(5S,6R,8S,9S,10R,13E)-6-acetoxycassa-13,15-diene (4). Compound 1 was chemically correlated with (−)-(5S,6R,8S,9S,10R,14R)-6-hydroxyvouacapane (2), (+)-(5S,8S,9S,10R,14R)-6-oxovouacapane (5), and (+)-(5S,6S,8S,9S,10R,14R)-6-acetoxyvouacapane (6), the last one previously isolated from Dipteryx lacunifera. The absolute configurations of all six diterpenes 1–6 were established by comparison of DFT calculated vibrational circular dicroism spectra of 1, 2 and 5 with those obtained experimentally. In addition, several reported chemical shifts for 2 and 5 were reassigned based on two-dimensional NMR measurements.