Design, synthesis, α-glucosidase inhibition, pharmacokinetic, and cytotoxic studies of new indole-carbohydrazide-phenoxy-N-phenylacetamide derivatives.

A new series of indole-carbohydrazide-phenoxy-N-phenylacetamide derivatives 7a-l were designed, synthesized, and screened for their α-glucosidase inhibitory abilities and cytotoxic effects. The results obtained in the α-glucosidase inhibition assay indicated that most of the synthesized derivatives displayed good to moderate inhibitory abilities (Ki values ranging from 14.65 ± 2.54 to 37.466 ± 6.46 µM) when compared with the standard drug acarbose (Ki = 42.38 ± 5.73 µM). Among them, 2-mehoxy-phenoxy derivatives 7l and 7h with 4-nitro and 4-chloro substituents on the phenyl ring of the N-phenylacetamide moiety, respectively, displayed the most inhibition effects. The inhibitory mechanism of these compounds was investigated by molecular docking studies. The in vitro cytotoxicity assay showed that only one compound, 2-methoxy-phenoxy derivative 7k with a 4-bromo substituent on the phenyl ring of the N-phenylacetamide moiety, exhibited moderate cytotoxicity against the human non-small-cell lung cancer cell line A549 and the rest of the compounds show almost no cytotoxicity. Further cytotoxic evaluations were also performed on compound 7k. The in silico pharmacokinetic study predicted that the selected compounds 7l and 7h are likely to be orally active.

Structure-based drug discovery and antimicrobial activity of ciprofloxacin-grafted Ugi adducts.

A new series of ciprofloxacin-derived Ugi adducts were rationally designed and synthesized. The synthesized molecules were explored for their potential antimicrobial activities against four pathogenic microorganisms. Among these derivatives, compound 7h with a 4-nitrophenyl substituent at R2 exhibited significant activity against two tested Gram-positive bacteria with a minimum inhibitory concentration value of 0.097 µg/mL while 7i bearing 4-chlorophenyl pendant demonstrated the best antimicrobial activities against Gram-negative bacteria. Furthermore, the analysis of the structure-activity relationships disclosed that types of substitutions differently affect the bacteria so the most potent derivative against Gram-negative infections was the least active one in Gram-positive microorganisms. Also, the molecular docking and molecular dynamic simulations were executed on 7i as the most potent Gram-negative anti-bacterial agent against ATP-binding sites of DNA gyrase B. Accordingly, our findings suggest that ciprofloxacin-based Ugi adducts are an interesting precursor for the design of potent antimicrobial agents.Communicated by Ramaswamy H. Sarma.

New quinoxalin-1,3,4-oxadiazole derivatives: Synthesis, characterization, in vitro biological evaluations, and molecular modeling studies.

A new series of quinoxalin-1,3,4-oxadiazole (10a-l) derivatives was synthesized and evaluated against some metabolic enzymes including human carbonic anhydrase (hCA) isoenzymes I and II (carbonic anhydrases I and II), cholinesterase (acetylcholinesterase and butyrylcholinesterase), and α-glucosidase. Obtained data revealed that all the synthesized compounds were more potent as compared with the used standard inhibitors against studied target enzymes. Among the synthesized compounds, 4-fluoro derivative (10f) against hCA I, 4-chloro derivative (10i) against hCA II, 3-fluoro derivative (10e) against acetylcholinesterase and butyrylcholinesterase, and 3-bromo derivative (10k) against α-glucosidase were the most potent compounds with inhibitory activity around 1.8- to 7.37-fold better than standard inhibitors. Furthermore, docking studies of these compounds were performed at the active site of their target enzymes.

Quinazolinone-dihydropyrano[3,2-b]pyran hybrids as new α-glucosidase inhibitors: Design, synthesis, enzymatic inhibition, docking study and prediction of pharmacokinetic.

A series of new quinazolinone-dihydropyrano[3,2-b]pyran derivatives 10A-L were synthesized by simple chemical reactions and were investigated for inhibitory activities against α-glucosidase and α-amylase. New synthesized compounds showed high α-glucosidase inhibition effects in comparison to the standard drug acarbose and were inactive against α-amylase. Among them, the most potent compound was compound 10L (IC50 value = 40.1 ± 0.6 µM) with inhibitory activity around 18.75-fold more than acarboase (IC50 value = 750.0 ± 12.5 µM). This compound was a competitive inhibitor into α-glucosidase. Our obtained experimental results were confirmed by docking studies. Furthermore, the cytotoxicity of the most potent compounds 10L, 10G, and 10N against normal fibroblast cells and in silico druglikeness, ADME, and toxicity prediction of these compounds were also evaluated.

Design, synthesis, characterization, enzymatic inhibition evaluations, and docking study of novel quinazolinone derivatives.

In this study, novel quinazolinone derivatives 7a-n were synthesized and evaluated against metabolic enzymes including α-glycosidase, acetylcholinesterase, butyrylcholinesterase, human carbonic anhydrase I, and II. These compounds exhibited high inhibitory activities in comparison to used standard inhibitors with Ki values in the range of 19.28-135.88 nM for α-glycosidase (Ki value for standard inhibitor = 187.71 nM), 0.68-23.01 nM for acetylcholinesterase (Ki value for standard inhibitor = 53.31 nM), 1.01-29.56 nM for butyrylcholinesterase (Ki value for standard inhibitor = 58.16 nM), 10.25-126.05 nM for human carbonic anhydrase I (Ki value for standard inhibitor = 248.18 nM), and 13.46-178.35 nM for human carbonic anhydrase II (Ki value for standard inhibitor = 323.72). Furthermore, the most potent compounds against each enzyme were selected in order to evaluate interaction modes of these compounds in the active site of the target enzyme. Cytotoxicity assay of the title compounds 7a-n against cancer cell lines MCF-7 and LNCaP demonstrated that these compounds do not show significant cytotoxic effects.