Acta Crystallographica Section E (Oct 2008)
Methyl [hydroxy(phenyl)phosphonomethyl]phosphonate methanol solvate
Abstract
The title compound, C8H12O7P2·CH4O, is a monoesterified bisphosphonate (or 1-hydroxymethylene-1,1-bisphosphonic acid). These synthetic compounds are widely used in medicine to inhibit bone resorption in diseases like osteoporosis, and are characterized by a stable P—C—P group and are thus analogs of inorganic pyrophosphate. By masking one or several ionizable groups, introduced as phosphonoester, it was anticipated the formation of prodrugs with higher lipophilicity that could facilitate the drug delivery and metabolization. Molecules are paired by intermolecular hydrogen bonds involving the phosphonic groups. In addition, dimers are connected side-by-side, building infinite ribbons along the a-axis direction; these ribbons are cross-linked perpendicularly along the b-axis direction via a methanol solvent molecule (disordered over two sites with occupancy factors ca 0.6 and 0.4), forming an extended intermolecular hydrogen-bonded network. The H atoms of the methyl group in the main molecule are disordered equally over two positions.