Hydrogen-bonding interactions in the 4-aminobenzoic acid salt of atenolol monohydrate.

Atenolol {or 4-[2-hydroxy-3-(isopropylamino)propoxy]phenylacetamide} crystallizes with 4-aminobenzoic acid to give the salt {3-[4-(aminocarbonylmethyl)phenoxy]-2-hydroxypropyl}isopropylammonium 4-aminobenzoate monohydrate, C14H23N2O3(+) x C7H6NO2(-) x H2O. In the crystal structure, the water molecule, the carboxylate group of 4-aminobenzoate, and the hydroxy and ether O atoms of atenolol form a supramolecular R3(3) (11) heterosynthon. Three other types of supramolecular synthons link the asymmetric unit into a two-dimensional structure.