Regio- and Diastereoselective Synthesis and X-ray Structure Determination of (+)-2-Deoxyoryzalexin S from (+)-Podocarpic Acid. Structural Nonidentity with Its Nominal Natural Isolated Enantiomer
Regio- and Diastereoselective Synthesis and X-ray Structure Determination of (+)-2-Deoxyoryzalexin S from (+)-Podocarpic Acid. Structural Nonidentity with Its Nominal Natural Isolated Enantiomer
Regio- and Diastereoselective Synthesis and X-ray Structure Determination of (+)-2-Deoxyoryzalexin S from (+)-Podocarpic Acid. Structural Nonidentity with Its Nominal Natural Isolated Enantiomer
作者:Francesca Leonelli、Valentina Latini、Andrea Trombetta、Gabriele Bartoli、Francesca Ceccacci、Angela La Bella、Alessio Sferrazza、Doriano Lamba、Luisa M. Migneco、Rinaldo Marini Bettolo
DOI:10.1021/np300518j
日期:2012.11.26
(+)-2-Deoxyoryzalexin S (1), the nominal enantiomer of a diterpenoid isolated in Chile from Calceolaria species, was regio- and diastereoselectively synthesized from (+)-podocarpic acid. (+)-2-Deoxyoryzalexin S (1) was characterized also as its acetyl derivative, (+)-2, whose structure was confirmed by X-ray crystallographic analysis. Surprisingly, comparison of the data recorded for (+)-1 and (+)-2 and those reported in the literature for the Calceolaria isolated diterpenoid 1 and its derivative (-)-2 showed some differences, suggesting that the latter do not possess the proposed structures.