一氧化氮及其生物活性蕴合物与辅酶NADPH反应机理研究

Reactions and reactions mechanism of nitric oxide and its donors with NADH models have been investigated systematically in this project. Important progress has been obtained in the following fields: (1) 74 NO donors with various structures were designed and synthesized, the dissociation energies of bond Y-NO (Y= N, O, S and Co) were determined, the energy scale of the Y-NO bond dissociation energies was established, which may be used to furnish hints to the understanding of the biological functions of NO and its donors in vivo. (2) The thermodynamics and kinetics of some important reactions of NO and its donors with NADH models were studied, the results may be used to clarify the reaction mechanisms. (3) Nature of Co-NO bond in cobalt(II) nitrosyl porphyrins and in cobalt(III) nitrosyl porphyrins was elucidated by Hammett-type linear free analyses on the relationship of the dissociation energies of Co-NO bond with the remote substituent effect, the results showed that the nitrosyl group carries negative charge of 0.49 and 0.27 in cobalt(II) nitrosyl porphyrins and in cobalt(III) nitrosyl porphyrins, respectively, which indicates that NO may be taken as a Lewis acid to react with cobalt porphyrins.

近年来大量研究表明，一氧化氮（NO）是一种生物信使分子，具有许多神奇的生理功能。烟酰胺辅酶是生命体内最重要的氧化还原辅酶之一，直接参与生命体内NO的生理合成和代谢过程。本项目首次从化学角度将系统地研究NO及其生物活性蕴合物与烟酰胺辅酶及其模型物在不同的拟生物微环境中反应机理。从分子水平上揭示NO在生命体内产生和代谢的奥秘。