Synthesis, Crystal Structure and DFT Studies of 8-chloro-3-((3-chlorobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine

Pyrrole-2,5-dione analogs as a promising antioxidant agents: microwave-assisted synthesis, bio-evaluation, SAR analysis and DFT studies/interpretation

A new series of pyrrole analogs were developed via the microwave irradiation synthesis. Consequently, got a high yield of the products. As pyrroles are familiar for showing various biological properties, all obtained compounds were screened for their antioxidant properties, most of the compounds showing significant activity. In fact, the motifs 5e, 5g, 5h and 5m showed outstanding antioxidant properties. Further, to enlighten the biologically energetic behavior underlying the antioxidant activity, compounds DFT studies were performed. Noteworthy results have been attained and the structure activity relationship (SAR) was discussed with the support of this results. It was found that highly biological active compounds exhibited a low HOMO-LUMO energy gap (Eg) and the high Eg value compounds show very low/negligible or inactive antioxidant activities. In other cases, compounds containing high HOMO energy levels also provide high antioxidant activity. The thought-provoking point of our results is that theoretical descriptors of the HOMO-LUMO energy gap and the highest occupied molecular orbital energy are important descriptors in the bioorganic research to support the biological experiments.

Novel aryloxyphenoxypropionate derivates containing benzofuran moiety: Design, synthesis, herbicidal activity, docking study and theoretical calculation

A series of novel aryloxyphenoxypropionate (APP) herbicides containing benzofuran moiety were designed, synthesized and tested for herbicidal activity. The bioassay results indicated that most of target compounds possessed moderate to good herbicidal activity against monocotyledonous weeds. Compounds 5a-5d and 6a-6d showed 100% control efficiency against crabgrass (Digitaria sanguinalis) and barnyard grass (Echinochloa crus-galli) in both pre-emergence and post-emergence treatments at the dosage of 1500 g a.i. ha^-1. Compound 6c was the most promising, with herbicidal activity better than clodinafop-propargyl. Molecular docking for compound 6c and its hydrolysis acid 1c were performed. ACCase activities of some compounds were also tested. Theoretical calculations for corresponding hydrolysis products 1a-1ewere carried out. Based on the results of molecular docking, enzyme activity test and theoretical calculation, the potential mechanism for herbicidal activity of these compounds was evaluated.

Design, synthesis, DFT study and antifungal activity of the derivatives of pyrazolecarboxamide containing thiazole or oxazole ring

Pyrazolecarboxamide fungicides are one of the most important classes of agricultural fungicides, which belong to succinodehydrogenase inhibitors (SDHIS). To discover new pyrazolecarboxamide analogues with broad spectrum and high activity, a class of new compounds of pyrazole carboxamide derivatives containing thiazole or oxazole ring were designed by scaffold hopping and bioisosterism, and 36 pyrazole carboxamide derivatives with antifungal activity were synthesized. Those compounds were evaluated against five phytopathogenic fungi, Gibberella zeae, Phytophythora capsici, Sclerotonia sclerotiorum, Erysiphe graminis and Puccinia sorghi. The results indicated that most of the compounds displayed good fungicidal activities, especially against E. graminis. Theoretical calculations were carried out at the B3LYP/6-31G (d, p) level and the full geometry optimization was carried out using the 6-31G (d, p) basis set, and the frontier orbital energy, atomic net charges, molecular docking were discussed, and the structure-activity relationships were also studied.

Design, Synthesis, DFT Study and Antifungal Activity of Pyrazolecarboxamide Derivatives

A series of novel pyrazole amide derivatives were designed and synthesized by multi-step reactions from phenylhydrazine and ethyl 3-oxobutanoate as starting materials, and their structures were characterized by NMR, MS and elemental analysis. The antifungal activity of the title compounds was determined. The results indicated that some of title compounds exhibited moderate antifungal activity. Furthermore, DFT calculations were used to study the structure-activity relationships (SAR).