QAAR exploration on pesticides with high solubility:An investigation on sulfonylurea herbicide dimers formed through π–π stacking interactions

Bioactive compounds could form aggregates that influence the bio-interactive processes. In this letter, based on π-π stacking models, quantitative aggregation-activity relationship （QAAR） studies were carried out on a series of sulfonylurea herbicides with good solubility. Four QAAR/QSAR models were constructed, which indicated that the bioactivity may strongly depend on both the characters of the dimeric aggregates and the monomer, The QAAR approach based on dimer-aggregates was also applicable for the highly water-soluble sulfonylurea herbicides that can form π-π stacking interactions. It was expected that the QAAR studies based on molecular aggregation state would be applied to other pesticide systems.

The exploration of chiral N-cyano sulfiliminyl dicarboxamides on insecticidal activities

Due to new mechanism of action and ecofriendly characteristics,dicarboxamide insecticides have attracted more and more attentions in modern pest management.A series of 20 dual chiral N-cyano sulfilimines containing two centers（carbon and sulfur） were designed and synthesized.All title compounds were determined by ^1H NMR,high-resolution mass spectrometry（HRMS） and optical polarimeter.The preliminary results indicated that some of them exhibited favourable insecticidal activities against oriental armyworm（Pseudaletia separata Walker）.These isomers exhibited different impact on activity following the sequence as（Sc,Ss） 〉（Sc,Rs）,and the rule of title compounds＇ activity against oriental armyworm was 3-CF3≥2—CH3—4—Cl〉2,3,4-trifluro in the anilide moiety.The results indicated that these groups such as 3-CF3,2—CH3—4—Cl or 2,3,4-trifluro were inefficient to replace heptafluoroisopropyl group for high larvicidal activity,which provided some guidance for the further modifications of sulfiliminyl dicarboxamides.

Qualitative Analysis and Approximate Damped Oscillatory Solutions for a Kind of Nonlinear Dispersive-dissipative Equation

This paper makes qualitative analysis to the bounded traveling wave solutions for a kind of nonlinear dispersive-dissipative equation, and considers its solving problem. The relation is investigated between behavior of its solution and the dissipation coefficient. Further, all approximate damped oscillatory solutions when dissipation coefficient is small are presented by utilizing the method of undetermined coefficients according to the theory of rotated vector field in planar dynamical systems. Finally, error estimate is given by establishing the integral equation which reflects the relation between approximate and exact damped oscillatory solutions applying the idea of homogenization principle.

Design,synthesis and insecticidal activities of novel anthranilic diamides containing fluorinated groups as potential ryanodine receptors activitors

In order to search for novel potent and environmentally benign insecticides,a series of anthranilic diamides containing various fluorinated groups were designed and synthesized.Their structures were confirmed by -1H NMR,-（13）C NMR,-（19）F NMR,elemental analysis,HRMS or mass spectra.Their insecticidal activities against oriental armyworm（Mythimna separata） and diamondback moth（Plutella xyiostella）were evaluated.The preliminary structure-activity relationship（SAR） was discussed in detail.The biological assay indicated that most of the compounds exhibited moderate to excellent insecticidal activities.Especially,Ia showed high larvicidal activity against oriental armyworm.Meanwhile,Iu had better larvicidal effects against diamondback moth than commercial chlorantraniliprole.

Synthesis and biological activities of some fluorine- and piperazine-containing 1,2,4-triazole thione derivatives

A series of fluorine- and piperazine-containing 1,2,4-triazole thione derivatives were synthesized by the Mannich reaction of triazole intermediates with various substituted piperazines and formaldehyde in high yields. Structures of title compounds were confirmed by melting points, IR,~1H NMR,^（13）C NMR and elemental analysis. The preliminary bioassays for 17 novel title compounds showed that several compounds have significant fungicidal activity against Cercospora arachidicola, Physalospora piricola and Rhizoctonia cerealis at 50 mg/m L.

Recursive Bayesian Algorithm for Identification of Systems with Non-uniformly Sampled Input Data

To identify systems with non-uniformly sampled input data, a recursive Bayesian identification algorithm with covariance resetting is proposed. Using estimated noise transfer function as a dynamic filter, the system with colored noise is transformed into the system with white noise. In order to improve estimates, the estimated noise variance is employed as a weighting factor in the algorithm. Meanwhile, a modified covariance resetting method is also integrated in the proposed algorithm to increase the convergence rate. A numerical example and an industrial example validate the proposed algorithm.

Synthesis,crystal structure and 3D-QSAR studies of antifungal (bis-) 1,2,4-triazole Mannich bases containing furyl and substituted piperazine moieties

A series of novel title compounds 6a-6r and 7a-7c have been synthesized by Mannich reaction of the new triazole Schiff base intermidiates, substituted piperazine and formaldehyde under mild conditions in excellent yields. The crystal structure of compound 6i was determined to show a chair conformation of the piperazine ring and an （E）-configuration of the C=N double bond. The bioassay results indicated that most of the newly synthesized compounds exhibited excellent in vitro inhibitory activities and broader spectrum against several plant fungi, and were more effective than the control Triadimefon. Several compounds also displayed favourable in vivo antifungal activities. The relationships between the compound structures and various biological activities were discussed. Furthermore, the CoMFA calculation based on the antifungal activity data of compounds 6 against R. cerealis was carried out to establish a 3D-QSAR model, which revealed that steric and electrostatic fields were two most important factors for contributing the bioactivity of the compounds. The present work will provide significant information for guiding optimization of such new structures to develop novel agrochemicals with higher antifungal activities.