Inhibitory effect of 4,4′-[ethane-1,2-diylbis(sulfandiylmethanediyl)]bis(3,5-dimethyl-1H-pyrazole) and its derivatives on alpha-amylase activity

Alpha-amylase as molecular target for treatment of diabetes mellitus: A comprehensive review

The alpha (α)-amylase is a calcium metalloenzyme that aids digestion by breaking down polysaccharide molecules into smaller ones such as glucose and maltose. In addition, the enzyme causes postprandial hyperglycaemia and blood glucose levels to rise. α-Amylase is a well-known therapeutic target for the treatment and maintenance of postprandial blood glucose elevations. Various enzymatic inhibitors, such as acarbose, miglitol and voglibose, have been found to be effective in targeting this enzyme, prompting researchers to express an interest in developing potent alpha-amylase inhibitor molecules. The review mainly focused on designing different derivatives of drug molecules such as benzofuran hydrazone, indole hydrazone, spiroindolone, benzotriazoles, 1,3-diaryl-3-(arylamino) propan-1-one, oxadiazole and flavonoids along with their target-receptor interactions, IC₅₀ values and other biological activities.

Synthesis, in vitro and in silico studies of inhibitory activity towards α-amylase of bis-azole scaffolds linked by an alkylsulfanyl chain

Twelve new α,ω-bis[(3,5-dimethylpyrazol-4-yl)methylsulfanyl]alkanes linked by alkyl, diethyl sulfide, and triethyl dioxide spacers were prepared by the multicomponent reaction of acetylacetone, formaldehyde, α,ω-dithiols, and monosubstituted hydrazines. Testing of these products for inhibition of α-amylase enzyme in vitro showed that bis(N-methylpyrazolylmethylsulfanyl)ethane 4a inhibits the enzyme by the competitive mechanism. Meanwhile, the water-soluble adduct of bis(isoxazolylmethylsulfanyl)ethane 2 with HCl (2·HCl) is a noncompetitive inhibitor. The molecular docking results attest to high complementarity between the test molecules and the enzymes such as α-amylases from Aspergillus niger and human pancreas. Bis-pyrazole compounds 1, 1·HCl, and 4a and bis-isoxazole compounds 2 and 2·HCl positioned in the active site of both α-amylases form two closely spaced clusters. For all cases, the bioactive conformations of the modeled ligands were identified, demonstrating high affinity of the bis-azoles (1, 1·HCl, 2, 2·HCl, 4a) to the enzymes. Hydrogen bonds stabilizing their position in both α-amylases active sites were identified.

Molecular Docking and Preclinical Study of Five-Membered S,S-Palladaheterocycle as Hepatoprotective Agent

Purpose: In order to investigate mechanisms underlying the hepatoprotective action of S,Spalladaheterocycle, inhibition of cytochromes P450 has been modeled by molecular docking of four palladaheterocycle stereoisomers to the active sites of an enzymatic oxidase system. To obtain a deeper insight into biochemical aspects providing a basis for the therapeutic effects of five-membered palladacycles (as mixture of stereoisomers), a number of preclinical trials has been conducted

Methods: 2D and 3D structures of palladaheterocycle stereoisomers were obtained via converting into SDF files by means of software MarvinSketch. Binding of palladaheterocycle at the active sites of cytochromes P450 2E1 and P450 2C9 has been studied by molecular docking using LeadIT 2.3.2. Hepatoprotective activity of palladaheterocycle at 2.5, 25 and 250 mg/kg doses has been studied based on a model of acute intoxication by CCl₄ using in vivo methods.

Results: By molecular docking it was identify amino acid fragments responsible for binding with palladacyclic isomers. The tested compound is comparable, in terms of its activity to the hepatoprotective drug SAM according to the in vivo and in vitro experiments such as animal survival data, the efficiency of correction of the cytolytic syndrome, the liver excretory function, carbohydrate, protein and lipid metabolism, and the correction efficiency of the liver antitoxic function (the latter has been determined based on the results of a hexobarbital control experiment).

Conclusion: Taking into account results obtained in vivo, in vitro and in silico, it can be concluded that the five-membered S,S-palladaheterocycle effectively protect the liver against acute damage caused by CCl₄ , via activation of catalase and glucuronyltransferase, as well as via inhibition of the oxidative stress enzymes.

Synthesis of Bis(Isoxazol-4-Ylmethylsulfanyl)Alkanes and Some Metal Complexes as a Hepatoprotective Agents

Purpose: This research is devoted to designing the synthesis of sulfanyl-substituted 3,5-dimethylisoxazoles, which contain structural analogues of the SAM drug in the molecule. SAM (S-adenosyl-L-methionine), formed in the biosynthetic process, is used as an effective hepatoprotective drug. Complexation and hepatoprotective properties of the combinatorial series of bis(isoxazolylsulfanyl)ethane have been studied. Methods: Bis(isoxazol-4-ylmethylsulfanyl)alkanes were synthesized using the one-pot method. The structures of compounds were established by one-dimensional (1H,13C) and two-dimensional (COSY, HCQS, HMBC) NMR spectroscopy, mass-spectrometry and X-ray diffraction. The biological activity of the combinatorial series of sulfanyl derivatives of diketones, azoles and their metal complexes has been studied by in vivo method. Simulation of the animal associated processes was carried out in accordance with the principles of bioethics. Screening studies of hepatoprotective activity were carried out in a model of acute CC14 intoxication after a single injection intraperitoneally as a 50% solution in olive oil. The pharmacologically known hepatoprotective drug SAM served as a control. Results: Two-step synthesis of novel α,ω-bis(isoxazol-4-ylmethylsulfanyl)alkanes was carried out via the multicomponent reaction between 2,4-pentandione, CH2O and α,ω-dithiols, then the resulting α,ω-bis(1,3-diketone-2-ylmethylsulfanyl)alkanes were transformed by hydroxyl amine to obtain bis-isoxasole derivatives. Promising precursor 1,2-bis(isoxazol-4-ylmethylsulfanyl)ethane was converted to metal complexes by interaction with PdCl2 or CuCl. The obtained compounds were found to be practically non-toxic compounds (1001 - 3000 mg/kg) according to the classification of K.K. Sidorov, but copper complex refers to low-toxic compounds substances (165 mg/kg). Compounds of sulfanyl ethane series demonstrate hepatoprotective activity. Conclusion: Palladium(II) complex being almost non-toxic possesses hepatoprotective activity comparable to the drug like SAM.