Crystal and molecular structure of a silver salt of antibiotic A-130A

Abstract

The crystal structure of the title compound has been determined by three-dimensional X-ray analysis from diffractometer data. Crystals are orthorhombic, space group P2₁2₁2₁, a= 28.179(5). b= 9.582(2). c= 18.096(3), Z= 4. The structure was solved by direct methods and refined by full-matrix least-squares calculations to R 0.065 for 3 977 independent observed reflexions. Hydrogen atoms were located. The absolute configuration was determined by the anomalous dispersion method. The molecule is wrapped around the Ag⁺ cation, and held in this configuration by two very strong hydrogen bonds between the carboxylate oxygen atoms and the two alcohol groups of the terminal six-membered ring.