Conformational Isomorphism of Organic Crystals: Racemic and Homochiral Atenolol

• Autor(a) principal: Castro, R. A. Esteves de
• Data de Publicação: 2007
• Outros Autores: Canotilho, João, Barbosa, Rui M., Silva, M. Ramos, Beja, A. Matos, Paixão, J. A., Redinha, J. Simões
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/10572; https://doi.org/10.1021/cg0601857

X-ray diffraction analysis of (R,S)- and S-atenolol crystalline forms was performed. The crystals studied were grown from evaporation of an ethanol/water solution. (R,S)-Atenolol crystallizes in the centrosymmetric space group C2/c, and S-atenolol crystallizes in a noncentrosymmetric space group C2. There is one symmetry independent molecule in (R,S)-atenolol crystals and two symmetry independent molecules in S-atenolol. However, due to disorder, two different molecular conformations were identified in the (R,S)-atenolol, and three different conformations were isolated in S-atenolol. Flexibility of molecular segments of the carbon chain is seen in conformational isomorphism and in the atomic position uncertainty. The molecular conformations given by X-ray diffraction were fully relaxed at the HF/6-31G* level of theory. The optimized structure was used as reference in comparison with molecular conformation in the solid state.