吡哆胺对1,4-二羰基化合物清除机理的密度泛函理论研究

吡哆胺（PM）能够清除生物体新陈代谢过程中产生的活性二羰基化合物，此类化合物能与体内的氨基酸作用生成有毒的吡咯类化合物。本文用密度泛函理论B3LYP方法在6-31G*基组水平上，研究了PM与OPA反应的机理。计算结果表明，该反应可通过两个连续的步骤完成。首先，通过竞争反应生成一个四氢吡咯类化合物；随后，该化合物经过平行反应脱水生成最终产物。理论上，反应过程中还有可能生成亚胺类化合物，但计算结果表明其为副反应。最后，本文讨论了空间位阻效应对反应性质的影响。所有计算结果与实验结果非常吻和。

Investigation on the Scavenging Mechanism of 1,4‐Dicarbonyls by Pyridoxamine: A Density Functional Theory Study

The dicarbonyl compound 4‐oxopentanal (OPA) is one of the reactive carbonyl species formed in a variety of metabolic reactions in vivo, which could react with lysyl residues to form pyrrolic compounds and exhibit severe toxicity. Pyridoxamine (PM) could effectively scavenge such reactive carbonyl compounds. The reaction mechanism of PM with OPA was investigated by density functional theory (DFT) B3LYP at 6‐31G?? basis level together with MP2/6‐31+G???? single point calculation on the stationary points. The results indicated that this reaction could be achieved through two continuous steps. Firstly, PM and OPA would generate a tetrahydropyrrole compound via two possible reaction pathways. Subsequently, two molecules of water would be removed to achieve the final pyrrole‐type compound through two parallel paths. In addition, it is possible to form an imine intermediate in this reaction, which seems more like a by‐product from our calculation. In the end, the steric hindrance of the acetyl group was discussed. All the results agreed with experiment very well.