Abstract:

The crystal size and the length to width ratio of nitrofurantoin (I) [67-20-9] can be controlled using an appropriate mixt. of solvents and suitable crystn. conditions. DMF formed undesirable complexes with I while with HCO2H [64-18-6] no crystal structure modification or complexation was detected. The length (y) to width (x) ratio of I varies from 2.5 to 1.5 when crystd. from pure HCO2H or in a mixt. with H2O or EtOH [64-17-5]. The y/x values corresponded to the solvent interactions and supersatn. The crystal growth regularity is ascribed to the solvent power and thus when more regular crystals will ppt. bioavailability and solubilization of the drug will increase. Best results were obtained when a mixt. of HCO2H-EtOH (2:1) soln. was used as the crystn. media yielding large tabular crystals. [on SciFinder(R)]