Crystal structure prediction for eniluracil

State-of-the-art molecular modeling tools were used to predict the crystal structure of eniluracil, a compound for which it has not been possible to g row a single crystal. Two methods were used, one that incorporates molecula r structure and powder X-ray diffraction data and another that employs mole cular structure and lattice energy calculations into the search algorithm. Two structures were identified, one with P2(1)/c and the other with P2(1) s ymmetry, both of which are consistent with the infrared and Raman spectra. A detailed analysis of the simulated and experimental powder X-ray diffract ion patterns indicates that the P21/c structure is the best representation of the crystal structure. (C) 2001 Wiley-Liss, Inc. and the American Pharma ceutical Association.