THE MOLECULAR STRUCTURE OF 4-AMINO 1-HYDROXY BUTYLIDENE-1 BISPHOSPHONIC ACID (AHBBPA); AN UNCOMMON ANHYDROUS HYDROXYBISPHOSPHONIC ACID

Abstract The molecular structure of an anhydrous hydroxybisphosphonic acid was determined by X-ray diffraction techniques and compared to the corresponding hydrated crystalline form. The hydrogen bond network and intermolecular interactions show that the polar bisphosphonic group undergoes a rotation to accomodate a different distribution in the hydrophobic/polar zones observed in the crystal packing, while the rest of the amino side chain connected to the functional carbon atom has identical conformation.