MS32-P20 Molecular and Crystal Structure Analysis of Two New Oxazol-5-One DerivativesTwo new oxazole-5-one derivatives, known as unsaturated azlactones, were synthesised due to the optical and biochemical importance [1,2]. These fluorescent molecules which are the cyclic anhydrides of N-acylaminoacids were formed by using Erlenmeyer azlactone reactions with aldehyde condensation. Molecular and crystal structures of 4-(N,N-diethylaminophenylmethylene)-2-(p-methoxyphenyl)oxazol-5-one (1) and 4-(N,N-diethylaminophenylmethylene)-2-(p-nitrophenyl)oxazol-5-one (2) have been determined by single crystal X-ray diffraction method. The data collections were carried out with Rigaku Oxford XCalibur diffractometer, cell refinements and data reductions were executed using CrysAlisPro program . Using Olex2, structures were solved with the SHELXT structure solution program and refined by full-matrix least-squares against F2 using SHELXL refinement package. The crystal structure of the compound 1 is stabilized π – π, C – H…π and C – H…O type weak interactions, while the crystal structure of the compound 2 is stabilized intermolecular π – π, N – O… π and C – H…O type weak interactions. There are also intramolecular C – H…N type weak interactions for both molecules.References:
 Öztürk. G. et al. (2008). Dyes Pigm. 76, 792–798.
 Khan. K. M. et al. (2008). Lett. Drug Des. Discovery. 5, 52–56.
 CrysAlisPro Software System, Version 18.104.22.168, Rigaku Corporation, Oxford, UK, 2015.Keywords: azlactone, X-ray crystallography, weak interactions