Atrazine (ATR) is a widely used herbicide. There are several types of reactions in its metabolism. Herein, the mechanism of three paths of hydrolysis reactions in its metabolism and predictions of toxicities of its metabolites in the three paths will be presented. The calculation results by B3LYP (Becke, 3-parameter, Lee–Yang–Parr), one of the approaches in density functional theory, indicated that (1) there were three models in the three hydrolysis paths of ATR. The dissociation mechanisms of C(9/11)–N(8/10), C(4/6)–N(8/10), and C–Cl were dealkylation, deamination, and Cl substitution, respectively. (2) The energy barrier of C–Cl dissociation was lower. The dissociation was advantageous in dynamics and the primary reaction in the three hydrolysis paths. In these hydrolysis reactions, the different intermediates had different concentrations because of the impact of the reaction rate. (3) In addition, it was necessary to consider the solvent effect to investigate hydrolysis reaction. The conductor-like polarizable continuum model (CPCM) was used to simulate the hydrolysis reaction in bond length and energy barrier because of the solvent effect. Experimental or predictive results showed that atrazine and its metabolites in the three hydrolysis paths were carcinogenic.

Diverse reactivity by coupling of substituted anilines with ethyl trifluoropyruvate was developed under microwave irradiation without catalysts to generate 3-trifluoromethyl-3-hydroxy oxindoles, aromatic hydroxy trifluoromethyl esters, and 1,2-dicarbonyl compounds in a fast and efficient manner. The plausible mechanism for obtaining different products was proposed. Furthermore, the anti-HIV activity of aromatic hydroxy trifluoromethyl esters was first reported. The best inhibitory activity against wild-type HIV-1 IIIB was exemplified by trifluoromethyloxindole 3q with an IC50 = 5.8 μM, which also displayed potential activity against Y181C mutant virus with an IC50 = 7.5 μM. More significantly, the activities of oxindoles 3q and 3r to inhibit K103N/Y181C double mutant HIV-1 reverse transcriptase (RT) are probably similar to that of the second-generation nonnucleoside inhibitor HBY 097 by docking calculation.

To increase efficiency of finding leads in pesticide design, reasonable screening rules for leads of fungicide, herbicide, and insecticide, respectively, are desired. Previous works showed that “Rule 5” of Lipinski is not a suitable screening rule for leads of pesticide and proposed rules for leads of fungicide, insecticide, and herbicide, which were combined by logarithmic ratio of octanol−water partition coefficient (log P), number of hydrogen bond donors, molecular weight, number of hydrogen bond acceptors, polar surface area, carcinogenic toxicity, and mutagenic toxicity. Herein, three sets of screening rules for leads of fungicide, insecticide, and herbicide, respectively, are presented. Each set of screening rules involves seven descriptors, which were selected by Kolmogorov−Smirnov test, ANOVA, Kruskal−Wallis test, and Pearson product-moment correlation, from more than 450 descriptors calculated by Codessa. Their accuracies are about 82, 83, and 89%, respectively.

Muscarinic M2 receptor antagonists with high subtype selectivity (M2/M1) will decrease the toxicity in central nervous system in treatment of AD. The exploration of quantitative structure–selectivity relationship (QSSR) to muscarinic M2 receptor antagonists will provide design information for drug with fewer side effects. In this paper, CoMFA models of pKi(M1), pKi(M2) and p[Ki(M2)/Ki(M1)] (pKi(M2) − pKi(M1)) were used to study the subtype selectivity (M2/M1) of piperidinyl piperidine derivatives as muscarinic M2 subtype receptor antagonists. The parameters of the three models are: 0.633, 0.636 and 0.726 for cross-validated r2 (rcv2), 0.109, 0.204 and 0.09 for the Standard error of estimate (SD), respectively. The results show the model of p[Ki(M2)/Ki(M1)] is the best one for design of piperidinyl piperidine derivatives as muscarinic antagonists with high subtype selectivity (M2/M1).A new M2/M1 quantitative structure–selectivity relationship (QSSR) model of piperidinyl piperidine derivatives as muscarinic M2 subtype receptor antagonists was constructed, discussed, and examined. This model could provide solid basis for designing novel molecules with higher antagonistic selectivity to muscarinic receptors.

The study of prediction of toxicity is very important and necessary because measurement of toxicity is typically time-consuming and expensive. In this paper, Recursive Partitioning (RP) method was used to select descriptors. RP and Support Vector Machines (SVM) were used to construct structure–toxicity relationship models, RP model and SVM model, respectively. The performances of the two models are different. The prediction accuracies of the RP model are 80.2% for mutagenic compounds in MDL’s toxicity database, 83.4% for compounds in CMC and 84.9% for agrochemicals in in-house database respectively. Those of SVM model are 81.4%, 87.0% and 87.3% respectively.

Diverse reactivity by coupling of substituted anilines with ethyl trifluoropyruvate was developed under microwave irradiation without catalysts to generate 3-trifluoromethyl-3-hydroxy oxindoles, aromatic hydroxy trifluoromethyl esters, and 1,2-dicarbonyl compounds in a fast and efficient manner. The plausible mechanism for obtaining different products was proposed. Furthermore, the anti-HIV activity of aromatic hydroxy trifluoromethyl esters was first reported. The best inhibitory activity against wild-type HIV-1 IIIB was exemplified by trifluoromethyloxindole 3q with an IC50 = 5.8 μM, which also displayed potential activity against Y181C mutant virus with an IC50 = 7.5 μM. More significantly, the activities of oxindoles 3q and 3r to inhibit K103N/Y181C double mutant HIV-1 reverse transcriptase (RT) are probably similar to that of the second-generation nonnucleoside inhibitor HBY 097 by docking calculation.