Crystal growth and characterization of methylenebisphosphonate partial esters

Various solution growth techniques were tested in an attempt to grow single crystals of four new partial esters of clodronic acid for X-ray structural studies. Gel (tetramethoxysilane) and vapour diffusion techniques proved to be successful. The starting materials and crystals were examined by infrared spectroscopy and thermogravimetric analysis and the structures of the starting materials were confirmed by ³¹P NMR and elemental analysis. Preliminary morphological studies were carried out by optical microscopy. These new bisphosphonate derivatives are of pharmaceutical interest as inhibitors of osteoclastic bone resorption.