2，6-二异丙基苯酚与金属离子的量子化学研究及其复合物特性

Quantum chemistry study and compounds property of 2, 6-diisopropylphenoi with metal ions

目的研究2，6-二异丙基苯酚与金属离子的相互作用。方法在Windows操作系统下使用量子化学计算软件Spartan＇02中的Hartree-Fock／6-311G法计算出2，6-二异丙基苯酚金属离子复合物的几何图形、电子转移、结合能等重要信息，并应用pH电位滴定法测量出2，6-二异丙基苯酚与Ca^2＋在27℃及37℃下形成复合物的稳定常数。结果AE（LUMO-HOMO），即最低空余分子轨道与最高占据分子轨道的能量差的排序为2，6-二异丙基苯酚-Ca^2＋〈2，6-二异丙基苯酚-Na^＋〈2，6-二异丙基苯酚-K^＋〈2，6-二异丙基苯酚。与2，6-二异丙基苯酚反应后，Ca^2＋、Na^＋、K^＋的正电子数分别减少了0．53、0．26和0．21个单位。结论2，6-二异丙基苯酚可与金属离子Ca^2＋、Na^＋、K^＋形成复合物，2，6-二异丙基苯酚与金属离子Ca^2＋形成的复合物的能力比其他两种金属离子要强，其与Ca^2＋在27℃及37℃下形成复合物的稳定常数分别为3．509±0．0126和3．526±0．0391（n=2）。2，6-二异丙基苯酚与金属离子Ca^2＋形成复合物的稳定常数相对其他Ca^2＋鳌合剂较小，这一点恰好符合丙泊酚的药效学特性。

Objective To investigate the interadion between the 2,6-diisopropylyhend and the metal ions. Methods Important information on geometries, charge transfer and binding energies between 2,6-diisopropylphenol and metal ions were obtained by Hartree-Fock/6-311G method based on Spartan＇02 software for Windows. The stability constants of 2,6-diisopropylphenol- Ca^2＋ compound at 27℃ and at 37℃ were determined by using pH titration method. Results The sequence of the energy difference between lowest unoccupied molecular orbital and highest occupied molecular orbital was 2,6-cliisopropylphenol-Ca^2 ＋〈2,6- diisopropylphenol -Na^＋〈2,6-diisopropylphenol -K^＋〈2,6 -diisopropylphenol. After reacting with 2,6 -diiso propylphenol, the decrease of the positive charge in Ca^2＋, Na^＋, and K^＋ was 0.53, 0.26, and 0.21 units, respectively. The stability constants of 2,6- diisopropylphenol-Ca^2＋ compound were 3.509 at 27℃ and 3.526 at 37℃. Conclusion 2,6-diisopropylphenol may form compounds with Ca^2＋, Na^＋, or K^＋, and 2,6-diisopropylphenol-Ca^2＋ compound is more stable than either of the other two ions. The stability constant of the compound 6-diisopropylphenol-Ca^2＋ is relatively small, which satisfies the pharmacodynamic characteristics of propofol.