Research Article: Erythromycin A dimethyl sulfoxide disolvate 1.43-hydrate

Date Published: March 01, 2012

Publisher: International Union of Crystallography

Author(s): Jürgen Brüning, Tanja K. Trepte, Jan W. Bats, Martin U. Schmidt.


The title compound, C37H67NO13·2C2H6OS·1.43H2O, is a macrolide anti­biotic with better solubility and better dermal penetration abilities than erythromycin A itself. The asymmetric unit of this form contains one erythromycin A mol­ecule, two dimethyl sulfoxide (DMSO) solvent mol­ecules, a fully occupied water mol­ecule and a partially occupied water mol­ecule with an occupancy factor of 0.432 (11). The 14-membered ring of the erythronolide fragment has a conformation which differs considerably from that in erythromycin A dihydrate [Stephenson, Stowell, Toma, Pfeiffer & Byrn (1997 ▶). J. Pharm. Sci.86, 1239–1244]. One of the two DMSO mol­ecules is disordered over two orientations; the orientation depends on the presence or absence of the second, partially occupied, water mol­ecule. In the crystal, erythromycin mol­ecules are connected by O—H⋯O hydrogen bonds involving the hy­droxy groups and the fully occupied water mol­ecule to form layers parallel to (010). These layers are connected along the b-axis direction only by a possible hydrogen-bonding contact involving the partially occupied water mol­ecule.

Partial Text

For a description of the title compound, see: Schmidt et al. (2011 ▶). For general background, see: Woodward et al. (1981 ▶). For crystallization experiments, see: Mirza et al. (2003 ▶). For related structures, see: Stephenson et al. (1997 ▶); Henry & Zhang (2007 ▶); Tian et al. (2009 ▶). For refinement details, see: Flack (1983 ▶); Spek (2009 ▶).