Ab initio structure determination of anhydrous sodium alendronate from laboratory powder X-ray diffraction data.

Sodium alendronate, a member of bisphosphonate class of compounds commonly used for treatment of generalized bone disorders, exists in various hydrated forms. Dehydration of sodium alendronate trihydrate has been studied using variable temperature X-ray powder diffraction technique. The crystal structure of anhydrous sodium alendronate, prepared by heating the trihydrate sodium alendronate at 150 degrees C, has been determined from X-ray powder data using direct space global optimization technique for structure solution, followed by the Rietveld refinement.