Hydroxy-alkyl bisphosphonic acid partial esters (HABPA-PE): Structures of two symmetrical and non-symmetrical members of a new class of prodrugs in bone disease treatments

Abstract

Abstract Two new hydroxy alkyl bisphosphonate partial esters (HABPA-PE) have been crystallised. The first compound C6H15NaO7P2C2H5O, crystallises as an ethanol solvate and forms rigid infinite β-sheet-like ribbons. The second, C6H16O7P2, displays self-association in dimers. In these new structures, packing analyses confirm the enhanced hydrophobic character due to partial esterification compared to naked hydroxybisphosphonic acids and the simplification of their H bonding patterns.