The higher anti‐human immunodeficiency virus activity of a symmetrical 2,2′‐disubstitued derivative of diphenyl disulfide (DPDS) has been explained by the lower energy of the lowest unoccupied molecular orbital (LUMO), resulted from a better hydrogen bond stabilization of the σ*_SS bond orbital (BO). This conclusion entails the participation of σ*_SS BO in constructing the LUMO. The higher content of σ*_SS BO, compared to π*_CC BOs of phenyl groups, in LUMO of DPDS has been found through analysis of the LUMO of DPDS expanded in the BO space. The high content of σ*_SS BO (%σ*_SS) in the LUMO of DPDS has laid the foundation for the formation of σ‐type radical anion intermediate in the stepwise reductive cleavage of disulfide bond in the symmetrical 4,4′‐disubstitued DPDS derivatives. For the nine 4,4′‐disubstituted DPDS‐derivatives under reductive cleavage studies, the increasing %σ*_SS in the LUMOs is parallel to the increasing value of inner reorganization energy.

中文翻译：

---

关于二苯二硫及其衍生物的某些化学性质的评论：II。将二硫键的还原性裂解研究与抗人类免疫缺陷病毒活性的研究（分子轨道特性最低）相关联

对称的2,2'-二苯基二硫化物（DPDS）的对称的2,2'-取代衍生物具有较高的抗人类免疫缺陷病毒活性，这是由于较低的未占据分子轨道（LUMO）的能量较低，这是由于其更好的氢键稳定性σ* _SS键轨道（BO）。该结论要求σ* _SS BO参与构建LUMO。通过分析在BO空间中扩展的DPDS的LUMO，发现DPDS的LUMO中的σ* _SS BO的含量高于苯基的π* _CC BOs。高含量的σ* _SS BO（％σ* _SS）在DPDS的LUMO中为在对称的4,4'-二取代的DPDS衍生物中二硫键的逐步还原裂解中形成σ型自由基阴离子中间体奠定了基础。对于在还原裂解研究中的九种4,4'-双取代的DPDS衍生物，LUMO中％σ* _SS的增加与内部重组能量的增加平行。