Molecular Docking and 3D-QSAR Studies of 4-Phenylpiperidine Derivatives as μ-Opioid Agonists

Abstract

A predictive 3D-QSAR model which correlates the biological activities with the chemical structures of a series of 4-phenylpiperidine derivatives as μ opioid agonists was developed by means of comparative molecular field analysis (CoMFA). The stabilities of the 3D-QSAR models were verified by the leave-one-out cross-validation method. Moreover, the predictive capabilities of the models were validated by an external test set. Best predictions were obtained with CoMFA standard model(q2=0.504, N=6, r2=0.968) which revealed how steric and electrostatic interactions contribute to agonists bioactivities, and provided us with important information to understand the interaction of agonists and μ opioid receptor .

Review of Theory and Practice on Natural Gas Hydrate

“…Fig. 4 The undersea gas hydrate zone of world's oceans and its geological location code map [32] In China, natural gas hydrate is mainly distributed in northern South China Sea continental slope, the Nansha Trough, East China Sea continental slop etc., and often distributed in sandstone, siltstone, silty mudstone and talus rock with massive, lenticular or disseminated shape. On the land, gas hydrate is mainly distributed in Qinghai-Tibet Plateau permafrost area up to 88 × 10 4 km 2 [17] .…”

“…The latter is more difficult and needs larger investment. [32] 4.1 NGH exploration technology Currently people often based on the core or gas samples, seabed parody reflection, the unusual geochemical features, seabed topography and shallow stratigraphy, electrical measurement, submarine gas spray columns, core pore water of low chloride concentration anomaly and other indicators to confirm occurrence and distribution of NGH. Thus the corresponding exploration techniques have come into being [33] .…”

“…The second is the drilling, deposits, mining, gathering and security technologies of natural gas hydrate. The latter is more difficult and needs larger investment [32].…”