水液相环境脯氨酸Ca(Ⅱ)配合物旋光异构的密度泛函理论研究  

Density Function Theoretical Study on the Optical Isomerism of Proline Ca(Ⅱ)Complex in Water-Liquid Phase Environment

作　　者：孟雪飞 张雪娇[2] 刘芳[3] 胡燠铭 陶思宇 黄煜纯 马宏源[3] 王佐成[3] MENG Xuefei;ZHANG Xuejiao;LIU Fang;HU Yuming;TAO Siyu;HUANG Yuchun;MA Hongyuan;WANG Zuocheng(Network Center,Changchun Normal University,Changchun 130000,Jilin,China;Network Center,Baicheng Normal University,Baicheng 137000,Jilin,China;College of Physics,Baicheng Normal University,Baicheng 137000,Jilin,China)

机构地区：[1]长春师范大学网络中心,吉林长春130000 [2]白城师范学院网络中心,吉林白城137000 [3]白城师范学院物理学院,吉林白城137000

出　　处：《武汉大学学报（理学版）》2021年第5期467-477,共11页Journal of Wuhan University:Natural Science Edition

基　　金：吉林省教育厅科学研究规划项目(JJKH20200002KJ);吉林省大学生创新项目(202010206066);吉林省自然科学基金(20130101131JC)。

摘　　要：采用基于密度泛函理论(DFT)的M06-2X和MN15方法结合自洽反应场理论的SMD模型方法,研究了水液相环境两性S-型脯氨酸(S-Pro)与Ca^(2+)配合物(S-Pro·Ca^(2+))的旋光异构。考察了S-Pro·Ca^(2+)在3个反应通道a、b和c的旋光异构过程:a通道是以羰基氧为质子迁移媒介;b通道是α-C上的质子先迁移至羰基氧,然后氨基氮上的质子在纸面内向α-C迁移;c通道是以羰基氧和氨基氮为质子迁移媒介。势能面研究表明:隐性溶剂效应下c通道明显具有优势,决速步能垒为221.4 k J/mol;显性溶剂效应下c通道略具优势,决速步能垒降到131.2 k J/mol。结果表明,脯氨酸钙在水液相环境只能很少量地消旋,其用于生命体同补脯氨酸和钙离子具有较好的安全性。The optical isomerism of amphoteric S-proline(S-Pro)and Ca^(2+)complexes(S-pro·Ca^(2+))has been studied in waterliquid phase environment by means of M06-2X and MN15 methods based on density functional theory and SMD model method of self-consistent reaction field theory.The optical isomerism of S-Pro·Ca^(2+)in three reaction channels has been investigated.Channel a uses the carbonyl O atom as the medium of protolysis.In channel b,the proton onα-C transfers to the carbonyl O atom,then the proton of amino group N atom transfers toα-C from inside the paper.Channel c uses the carbonyl O atom and the amino group N atom as the medium of protolysis.The potential energy surface shows that channel c has the most advantages under the effect of recessive solvent,and the energy barrier of the rate-determining step is 221.4 k J/mol;channel c has the most advantages under the dominant solvent effect,and the energy barrier of the rate-determining step is reduced to 131.2 k J/mol.The results show that S-Pro·Ca^(2+)can racemize with only a small amount in the water-liquid environment,and it is relatively safe to be used to supply proline and Ca^(2+)for life simultaneously.

关 键 词：氨基酸金属配合物 密度泛函理论 自洽反应场理论 旋光异构 过渡态 能垒 

分 类 号：O641.12[理学—物理化学]