Absolute configuration of axially chiral bisquinolones: DFT calculations and X-ray crystallography
Cruz Borbolla, Julian
2015
Formal synthesis of (-)-flustramine B and its absolute configuration assignment by vibrational circular dichroism exciton chirality, Reyna E. Cordero-Rivera, Myriam Meléndez-Rodríguez, Oscar R. Suárez-Castillo, Claudia I. Bautista-Hernández, Nayely Trejo-Carbajal, Julián Cruz-Borbolla, Luis E. Castelán-Duarte, Martha S. Morales-Ríos, Pedro Joseph-Nathanb, Tetrahedron Asymmetry, doi:10.1016/j.tetasy.2015.05.009
Abstract
A formal synthesis of the natural product (?)-flustramine B (3) is described, together with an easy and reliable approach for the absolute configuration assignment of a series of (3R,14S)- and (3S,14S)-oxindolylacetylphenyloxazolidinones 4, 6, 13a?c, and amides (+)- and (?)-14 by evaluation of the vibrational circular dichroism bisignated couplet resulting from the interaction of the C2 and C9 carbonyl groups. The absolute configuration assignment was validated by 1H NMR spectra and X-ray diffraction, and therefore (?)-flustramine B 3 was established as (3aS,8aR)-3.
