Cover Picture: Insight into the Structural Requirements of Protoporphyrinogen Oxidase Inhibitors: Molecular Docking and CoMFA of Diphenyl Ether, Isoxazole Phenyl, and Pyrazole Phenyl Ether (Chin. J. Chem. 9/2013)

The cover picture shows that a multistep framework is developed with the ultimate goal of identifying novel herbicides. Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is one of the most significant targets for herbicide design. Using the crystal structure of tobacco mitochondrial PPO (mtPPO) as template, inhibitors were docked into the active site. The docking pose of each compound was subsequently used in a receptor-based alignment, leading to the development of a significant CoMFA model with r2 value of 0.98 and q2 (cross validation r2) value of 0.63. This novel multistep framework gives insight into the structural characteristics for the binding of inhibitors. In addition, the simplicity of the proposed approach may be particularly applicable in virtual screening procedures. More details are discussed in the article by Yang et al. on page 1153–1158.