POLYMORPHISM AND CHIRALITY OF N-PHENYL-N'-[1-(3-(1-PHENYL-4-PIPERAZINO)PROPAN-2-OL)]UREA

The various crystalline forms of an original heterocyclic compound. N-phenyl-N'-[1-(3-phenyl-4-piperazinyl)propane-2-ol)]urea (PU), have been obtained and characterized using X-ray diffraction, DSC, thermo and optical system and IR spectrometry. At 20 degrees C the racemic PU crystallizes from trichloroethylene as an orthorhombic racemate (R(o)) or from methanol as a monoclinic racemate (R(m)). Using the GUINIER-SIMON camera by increasing the temperature we observed progressive transformation of R(m) (metastable) into R(o) (stable). At higher temperature (>190 degrees C) PU may be cyclized in the corresponding 2-oxazolidinone with elimination of an aniline molecule. A conglomerate (C) can be obtained from PU after controlled melting, quenching and devitrification. An enantiomer (E(o)) can be obtained from (C) by solubilization in methanol followed by the solvent evaporation. The calculated binary diagram of the two antipodes E(o) (+) and E(o) has been established using the thermic analysis results.