Computer-Based Conformational Analysis of Acetylcholine and Muscarine Combined with an Overview of the Receptor-Ligand Interaction

Drug development is among the topics studied in the pharmaceutical chemistry course for pharmacy undergraduates of Universidade Federal de Minas Gerais, Brazil. Computational advances in the last 20 years together with the availability of user-friendly software have promoted the development of simple computer-assisted molecular-modeling experiments for bioactive molecules. The knowledge of the specific stereochemistry of active sites for enzymes and some receptor sites justifies the study of drug conformations capable of interacting with these sites. Only a single conformation from the many possible conformations of a flexible molecule can bind to the receptor site. We report a procedure to perform conformational analysis using the systematic search method and the superimposition of two bioactive molecules, acetylcholine and muscarine. The undergraduate students individually perform the proposed procedure using a personal computer.