Absolute configuration of esquelane derivatives from Adesmia boronioides by vibrational circular dichroism

作者：Cerda Garcia Rojas Carlos M^*; Bucio Maria A; Gonzalez Silvia B; Garcia Gutierrez Hugo A; Joseph Nathan Pedro

来源：Tetrahedron: Asymmetry , 2015, 26(2-3): 136-140.

DOI：10.1016/j.tetasy.2014.12.003

The absolute configurations of natural esquelane derivatives 1 and 2, the main components of a commercially available fragrance, as well as their synthetic derivatives 3-7 were revised by using the vibrational circular dichroism (VCD) spectroscopy of 2 and 6 in combination with density functional theory calculations at the B3LYP/DGDZVP level of theory. The agreement between the experimental and calculated VCD spectra of these bisnorsesquiterpenes revealed that they are in fact (1S,4R,5S)-esquel-6-en-9-one 1 and (1S,4R,5R)-esquel-7-en-9-one 2 instead of the formerly reported enantiomers. The VCD method was also applied to cacalol acetate 9 in order to verify its absolute configuration, since cacalol 8 was previously used as a comparative motif to determine the absolute configuration of esquelane derivatives.

• 出版日期2015-2-15