Vadimezan: 2-(5,6-dimethyl-9-oxo-9H-xanthen-4-yl)acetic acid

Abstract

In the title molecule, C17H14O4, the C atom of the carboxyl group deviates by 1.221 (3) Å from the plane [maximum deviation = 0.0122(2) Å] of the tricycic ring system. In the crystal structure, intermolecular O—H...O hydrogen bonds link the molecules into centrosymmetric dimers, and π–π interactions [centroid–centroid distances = 3.491 (3), 3.591 (3), 3.639 (3) and 3.735 (3) Å] link these dimers into layers parallel to the ac plane. Weak intermolecular C—H...O interactions further consolidate the crystal packing.