In silico and in vitro studies of thiosemicarbazone-indole hybrid compounds as potent α-glycosidase inhibitors.

It is essential to study α-glucosidase enzyme (EC 3.2.1.20) inhibitors because of their physiological role as well as their clinical relevance. In previous research, a novel series of thiosemicarbazone-indole hybrid compounds were synthesized and reported. In the current research, α-glucosidase inhibitory activity of the derivatives was evaluated and then in silico studies were carried out on screened compounds. All derivatives exhibited a magnificent α-glucosidase inhibitory activity (IC50 = 27.0 ± 1.0-97.4 ± 1.5 µM) toward the acarbose as reference drug (IC50 = 750.0 ± 1.5 µM). Compound 1i having phenyl ring at the thiosemicarbazone moiety and the trimethoxymethyl substituent at phenyl moiety of C2 position of indole ring was the most potent compound (IC50 = 27.0 ± 1.0 µM) among other compounds. A kinetic study of 1i revealed that is a competitive inhibitor against α-glucosidase. Moreover, the molecular docking studies established that screened derivatives interacted with the essential amino acids in the active site. Finally, based on the molecular dynamics simulations and free binding energy calculations, complexes 1d, 1i and 1k with α-glucosidase showed a good stability in the active site. Van der Waals and electrostatic interactions also exhibited the most contributions to the stability of these complexes. Moreover, all the screened compounds showed agreeable ADME properties for oral bio-availability, and good drug-likeness.

Design and Synthesis of Novel Cytotoxic Indole-Thiosemicarbazone Derivatives: Biological Evaluation and Docking Study.

In this work, two novel series of indole-thiosemicarbazone derivatives were designed, synthesized, and evaluated for their cytotoxic activity against MCF-7, A-549, and Hep-G2 cell lines in comparison to etoposide and colchicine as the reference drugs. Generally, the synthesized compounds showed better cytotoxicity towards A-549 and Hep-G2 than MCF-7. Among them, (2E)-2-{[2-(4-chlorophenyl)-1H-indol-3-yl]methylidene}-N-(4-methoxyphenyl)hydrazinecarbothioamide (8l) was found to be the most potent compound against A-549 and Hep-G2, at least three times more potent than etoposide. The morphological analysis by the acridine orange/ethidium bromide double staining test and flow cytometry analysis indicated that compound 8l induced apoptosis in A-549 cells. Moreover, molecular docking methodology was exploited to elucidate the details of molecular interactions of the studied compounds with putative targets.

Fabrication of a novel nanocomposite based on sol-gel process for hollow fiber-solid phase microextraction of aflatoxins: B1 and B2, in cereals combined with high performane liquid chromatography-diode array detection.

The new pre-concentration technique, hollow fiber-solid phase microextraction based on carbon nanotube reinforced sol-gel and liquid chromatography-photodiode array detection was applied to determination of aflatoxins B(1), B(2) (AFB(1), AFB(2)) in rice, peanut and wheat samples. This research provides an overview of trends related to synthesis of solid phase microextraction (SPME) sorbnents that improves the assay of aflatoxins as the semi-polar compounds in several real samples. It mainly includes summary and a list of the results for a simple carbon nanotube reinforced sol-gel in-fiber device. This device was used for extraction, pre-concentration and determination of aflatoxins B1, B2 in real samples. In this technique carbon nanotube reinforced sol was prepared by the sol-gel method via the reaction of phenyl trimethoxysilane (PTMS) with a basic catalyst (tris hydroxymethyl aminomethan). The influences of microextraction parameters such as pH, ageing time, carbon nanotube contents, desorption conditions, desorption solvent and agitation speed were investigated. Optimal HPLC conditions were: C(18) reversed phase column for separation, water-acetonitril-methanol (35:10:55) as the mobile phase and maximum wavelength for detection was 370 nm. The method was evaluated statistically and under optimized conditions, the detection limits for the analytes were 0.074 and 0.061 ng/mL for B1 and B2 respectively. Limit of quantification for B1 and B2 was 0.1 ng/mL too (n=7). The precisions were in the range of 2.829-2.976% (n=3), and linear ranges were within 0.1 and 400 ng/mL. The method was successfully applied to the analysis of cereals (peanut, wheat, rice) with the relative recoveries from 47.43% to 106.83%.