ONIOM study of one-carbon unit transfer from imidazolidine to dUMP analogue

The ONIOM quantum mechanics method is used in this article to study one-carbon unit transfer from an imidazolidine to 6-aminouracil derivates. The computation results show that this reaction can be completed via three paths, owing to the three different proton transfer modes. Each path experiences three processes of nucleophile attacking, proton transferring, and bond rupturing. The focus of discussion falls on the proton transfer process. By analyzing the calculation results, we find that the direct proton transfer is the preferable pathway. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004