The crystal structure of 3-hydroxy-3-isobutyl-2-pyrrolidone-5-carboxylic acid, lactam of 4-hydroxy-4-isobutylglutamic acid from Reseda odorata L.

Abstract

The relative configuration of 3-hydroxy-3-isobutyl-2-pyrrolidone-5-carboxylic acid has been determined by an X-ray crystal structure analysis. The compound crystallized in space group P212121 with two molecules in the asymmetric unit. a=16.023(3) A, b=19.349(7) A, c=6.9053(16) A. The structure was solved by direct methods using MULTAN and refined by full-matrix least-squares technique to an R of 0.137 for 645 diffractometer-collected intensities. The absolute configurations of the title compounds were deduced; the configuration of the amino acid and the lactam are 2(S), 4(S) and 3(S), 5(S), respectively.