Rational Design, Synthesis, in Vitro, and in Silico Studies of Chlorophenylquinazolin-4(3H)-One Containing Different Aryl Acetohydrazides as Tyrosinase Inhibitors.

Tyrosinase plays a pivotal role in the hyperpigmentation and enzymatic browning of fruit and vegetable. Therefore, tyrosinase inhibitors can be of interest in industries as depigmentation compounds as well as anti-browning agents. In the present study, a series of chlorophenylquinazolin-4(3H)-one derivative were rationally designed and synthesized. The formation of target compounds was confirmed by spectral characterization techniques such as IR, 1 H-NMR, 13 C-NMR, and elemental analysis. Among the synthesized derivatives, compound 8l was proved to be the most potent inhibitor with an IC50 value of 25.48±1.19 µM. Furthermore, the results of the molecular docking study showed that this compound fitted well in the active site of tyrosinase with the binding score of -10.72.

Design and synthesis of phenoxymethybenzoimidazole incorporating different aryl thiazole-triazole acetamide derivatives as α-glycosidase inhibitors.

A novel series of phenoxymethybenzoimidazole derivatives (9a-n) were rationally designed, synthesized, and evaluated for their α-glycosidase inhibitory activity. All tested compounds displayed promising α-glycosidase inhibitory potential with IC50 values in the range of 6.31 to 49.89 µM compared to standard drug acarbose (IC50 = 750.0 ± 10.0 µM). Enzyme kinetic studies on 9c, 9g, and 9m as the most potent compounds revealed that these compounds were uncompetitive inhibitors into α-glycosidase. Docking studies confirmed the important role of benzoimidazole and triazole rings of the synthesized compounds to fit properly into the α-glycosidase active site. This study showed that this scaffold can be considered as a highly potent α-glycosidase inhibitor.

Arylmethylene hydrazine derivatives containing 1,3-dimethylbarbituric moiety as novel urease inhibitors.

A new series of arylmethylene hydrazine derivatives bearing 1,3-dimethylbarbituric moiety 7a-o were designed, synthesized, and evaluated for their in vitro urease inhibitory activity. All the title compounds displayed high anti-urease activity, with IC50 values in the range of 0.61 ± 0.06-4.56 ± 0.18 µM as compared to the two standard inhibitors hydroxyurea (IC50 = 100 ± 0.15 µM) and thiourea (IC50 = 23 ± 1.7 µM). Among the synthesized compounds, compound 7h with 2-nitro benzylidene group was found to be the most potent compound. Kinetic study of this compound revealed that it is a mix-mode inhibitor against urease. Evaluation of the interaction modes of the synthesized compounds in urease active site by molecular modeling revealed that that compounds with higher urease inhibitor activity (7h, 7m, 7c, 7l, 7i, and 7o, with IC50 of 0.61, 0.86, 1.2, 1.34, 1.33, 1.94 µM, respectively) could interact with higher number of residues, specially Arg609, Cys592 (as part of urease active site flap) and showed higher computed free energy, while compounds with lower urease activity (7f, 7n, 7g, and 7a with IC50 of 3.56, 4.56, 3.62 and 4.43 µM, respectively) and could not provide the proper interaction with Arg609, and Cys592 as the key interacting residues along with lower free binding energy. MD investigation revealed compound 7h interacted with Arg609 and Cys592 which are of the key residues at the root part of mobile flap covering the active site. Interacting with the mentioned residue for a significant amount of time, affects the flexibility of the mobile flap covering the active site and causes inhibition of the ureolytic activity. Furthermore, in silico physico-chemical study of compounds 7a-o predicted that all these compounds are drug-likeness with considerable orally availability.

The natural-based optimization of kojic acid conjugated to different thio-quinazolinones as potential anti-melanogenesis agents with tyrosinase inhibitory activity.

Melanin pigment and melanogenesis are a two-edged sword. Melanin has a radioprotection role while melanogenesis has undesirable effects. Targeting the melanogenesis pathway, a series of kojyl thioether conjugated to different quinazolinone derivatives were designed, synthesized, and evaluated for their inhibitory activity against mushroom tyrosinase. All the synthesized compounds were screened for their anti-tyrosinase activity and all derivatives displayed better potency than kojic acid as the positive control. In this regard, 5j and 5h as the most active compounds showed an IC50 value of 0.46 and 0.50 µM, respectively. In kinetic evaluation against tyrosinase, 5j depicted an uncompetitive inhibition pattern. Designed compounds also exhibited mild antioxidant capacity. Moreover, 5j and 5h achieved good potency against the B16F10 cell line to reduce the melanin content, whilst showing limited toxicity against malignant cells. The proposed binding mode of new inhibitors evaluated through molecular docking was consistent with the results of structure-activity relationship analysis.

Design and synthesis of 4,5-diphenyl-imidazol-1,2,3-triazole hybrids as new anti-diabetic agents: in vitro α-glucosidase inhibition, kinetic and docking studies.

Fourteen novel 4,5-diphenyl-imidazol-1,2,3-triazole hybrids 8a-n were synthesized with good yields by performing click reaction between the 4,5-diphenyl-2-(prop-2-yn-1-ylthio)-1H-imidazole and various benzyl azides. The synthesized compounds 8a-n were evaluated against yeast α-glucosidase, and all these compounds exhibited excellent inhibitory activity (IC50 values in the range of 85.6 ± 0.4-231.4 ± 1.0 µM), even much more potent than standard drug acarbose (IC50 = 750.0 µM). Among them, 4,5-diphenyl-imidazol-1,2,3-triazoles possessing 2-chloro and 2-bromo-benzyl moieties (compounds 8g and 8i) demonstrated the most potent inhibitory activities toward α-glucosidase. The kinetic study of the compound 8g revealed that this compound inhibited α-glucosidase in a competitive mode. Furthermore, docking calculations of these compounds were performed to predict the interaction mode of the synthesized compounds in the active site of α-glucosidase. A novel series of 4,5-diphenyl-imidazol-1,2,3-triazole hybrids 8a-n was synthesized with good yields by performing click reaction between the 4,5-diphenyl-2-(prop-2-yn-1-ylthio)-1Himidazole and various benzyl azides. The synthesized compounds 8a-n were evaluated against yeast α-glucosidase and all these compounds exhibited excellent inhibitory activity (IC50 values in the range of 85.6 ± 0.4-231.4 ± 1.0 µM), even much more potent than standard drug acarbose (IC50 = 750.0 µM).

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.

On various Riesz-dual sequences for Schauder frames.

In this paper, we introduce various definitions of R-duals, to be called R-duals of type I, II, which leads to a generalization of the duality principle in Banach spaces. A basic problem of interest in connection with the study of R-duals in Banach spaces is that of characterizing those R-duals which can essentially be regarded as M-basis. We give some conditions under which an R-dual sequence to be an M-basis for X.

Design, synthesis, in vitro, and in silico studies of novel diarylimidazole-1,2,3-triazole hybrids as potent α-glucosidase inhibitors.

In this work, new derivatives of diarylimidazole-1,2,3-triazole 7a-p were designed, synthesized, and evaluated for their in vitro α-glucosidase inhibitory activity. All compounds showed potent inhibitory activity in the range of IC50 = 90.4-246.7 µM comparing with acarbose as the standard drug (IC50 = 750.0 µM). Among the synthesized compounds, compounds 7b, 7c, and 7e were approximately 8 times more potent than acarbose. The kinetic study of those compounds indicated that they acted as the competitive inhibitors of α-glucosidase. Molecular docking studies were also carried out for compounds 7b, 7c, and 7e using modeled α-glucosidase to find the interaction modes responsible for the desired inhibitory activity.

Biscoumarin-1,2,3-triazole hybrids as novel anti-diabetic agents: Design, synthesis, in vitro α-glucosidase inhibition, kinetic, and docking studies.

A novel series of biscoumarin-1,2,3-triazole hybrids 6a-n was prepared and evaluated for α-glucosidase inhibitory potential. All fourteen derivatives exhibited excellent α-glucosidase inhibitory activity with IC50 values ranging between 13.0 ±â€¯1.5 and 75.5 ±â€¯7.0 µM when compared with the acarbose as standard inhibitor (IC50 = 750.0 ±â€¯12.0 µM). Among the synthesized compounds, compounds 6c (IC50 = 13.0 ±â€¯1.5 µM) and 6g (IC50 = 16.4 ±â€¯1.7 µM) exhibited the highest inhibitory activity against α-glucosidase and were non-cytotoxic towards normal fibroblast cells. Kinetic study revealed that compound 6c inhibits the α-glucosidase in a competitive mode. Furthermore, molecular docking investigation was performed to find interaction modes of the biscoumarin-1,2,3-triazole derivatives.