Novel acyl hydrazide derivatives of polyhydroquinoline as potent anti-diabetic and anti-glycating agents: Synthesis, in vitro α-amylase, α-glucosidase inhibition and anti-glycating activity with molecular docking insights.

In this study, eleven novel acyl hydrazides derivative of polyhydroquinoline were synthesized, characterized and screened for their in vitro anti-diabetic and anti-glycating activities. Seven compounds 2a, 2d, 2i, 2 h, 2j, 2f, and 2 g exhibited notable α-amylase inhibitory activity having IC50 values from 3.51 ± 2.13 to 11.92 ± 2.30 µM. Similarly, six compounds 2d, 2f, 2 h, 2i, 2j, and 2 g displayed potent α-glucosidase inhibitory activity compared to the standard acarbose. Moreover, eight derivatives 2d, 2 g, 2f, 2j, 2a, 2i, 2 g, and 2e showed excellent anti-glycating activity with IC50 values from 6.91 ± 2.66 to 15.80 ± 1.87 µM when compared them with the standard rutin (IC50 = 22.5 ± 0.90 µM). Molecular docking was carried out to predict the binding modes of all the compounds with α-amylase and α-glucosidase. The docking analysis revealed that most of the compounds established strong interactions with α-amylase and α-glucosidase. All compounds fitted well into the binding pockets of α-amylase and α-glucosidase. Among all compounds 2a and 2f were most potent based on docking score -8.2515 and -7.3949 against α-amylase and α-glucosidase respectively. These results hold promise for the development of novel candidates targeted at controlling postprandial glucose levels in individuals with diabetes.

2-Aminothiazole-Oxadiazole Bearing N-Arylated Butanamides: Convergent Synthesis, Tyrosinase Inhibition, Kinetics, Structure-Activity Relationship, and Binding Conformations.

A multi-step synthesis of novel bi-heterocyclic N-arylated butanamides was consummated through a convergent strategy and the structures of these medicinal scaffolds, 7a-h, were corroborated using spectral techniques. The in vitro analysis of these hybrid molecules revealed their potent tyrosinase inhibition as compared to the standard used. The kinetics mechanism was investigated through Lineweaver-Burk plots which exposed that, 7f, inhibited tyrosinase enzyme non-competitively by forming the enzyme-inhibitor complex. The inhibition constants Ki calculated from Dixon plots for this compound was 0.025 µM. Their binding conformations were ascertained by in silico computational studies whereby these molecules disclosed good binding energy values (kcal/mol). So, it was anticipated from the current research that these bi-heterocyclic butanamides might be probed as imperative therapeutic agents for melanogenesis.

Synthesis and Molecular Docking of New Bis-Thiazolidinone-Based Chalcone Analogs as Effective Inhibitors of Acetylcholinesterase and Butyrylcholinesterase.

This work reports the convenient strategy for the synthesis of bis-thiazolidinone based chalcone analogs (1-20) from readily available thiosemicarbazide hydrochloride, ammonium thiocyanate and benzaldehyde. All the newly afforded bis-thiazolidinone based chalcone analogs (1-20) were screened in vitro for their acetylcholinesterase and butyrylcholinesterase inhibition profile. It was noteworthy, that all the synthetic analogs (except analogs 10, 12 and 14, which are found to be inactive) showed moderate to good inhibitory potentials on screening against acetylcholinesterase having range of inhibitory with IC50 values from 0.070±0.050 to 7.60±0.10 µM, and similarly for butyrylcholinesterase with range IC50 values from 0.10±0.050 µM to 10.70±0.20 µM, respectively as compared to standard Donepezil inhibitor (IC50 =2.16±0.12 µM), (IC50 =4.5±0.11 µM).Among the series, the analogs with hydroxy group showed superior inhibitory potentials against acetylcholinesterase and butyrylcholinesterase enzymes. Therefore, analog 20 (IC50 =0.070±0.050 µM), (IC50 =0.10±0.050 µM) bearing trihydroxy substitutions on ortho-, meta- and para-position of both rings A and B was found to be the most active inhibitor of acetylcholinesterase and butyrylcholinesterase enzymes among the current synthesized series (1-23). Analog 19 (IC50 =0.15±0.050 µM), (IC50 =0.20±0.050 µM) bearing dihydroxy substitutions on ortho- and meta-position of both ring A and ring B was identified as the second most potent inhibitor against both these enzymes. Interestingly, the compound (16) (IC50 =1.50±0.10 µM against AChE) has a better selectivity index (2.60) than standard Donepezil drug (2.083) for AChE over BuChE. The different types of spectroscopic techniques such as HR-EI-MS, 1 H- and 13 C- NMR were used to confirm the structure of all the newly synthetics analogs. To find structure-activity relationship, molecular docking studies were carried out to understand the binding mode of active inhibitors with active site of enzymes and results supported the experimental data.

Synthesis, thymidine phosphorylase, angiogenic inhibition and molecular docking study of isoquinoline derivatives.

Isoquinoline analogues (KA-1 to 16) have been synthesized and evaluated for their E. coli thymidine phosphorylase inhibitory activity. Except compound 11, all other analogs showed outstanding thymidine inhibitory potential ranging in between 4.40 ±â€¯0.20 to 69.30 ±â€¯1.80 µM when compared with standard drug 7-Deazaxanthine (IC50 = 38.68 ±â€¯4.42 µM). Structure Activity Relationships has been established for all compounds, mainly based on substitution pattern on phenyl ring. All analogs were characterized by various spectroscopic techniques such as 1H NMR, 13C NMR and EI-MS. The binding interactions of isoquinoline analogues with the active site of TP enzyme, the molecular docking studies were performed. Furthermore, the angiogenic inhibitory potentials of isoquinoline analogues (KA-1-9, 14, 12 and 16) were determined in the presence of standard drug Dexamethasone based on percentage inhibitions at various concentrations. Herein this work analogue KA-12, 14 and 16 emerged with most potent angiogenic inhibitory potentials among the synthesized analogues.

ß-Sitosterol from Ifloga spicata (Forssk.) Sch. Bip. as potential anti-leishmanial agent against leishmania tropica: Docking and molecular insights.

The current study was aimed to evaluate the anti-leishmanial potentials of ß-sitosterol isolated from Ifloga spicata. The anti-leishmanial potential of ß-sitosterol is well documented against Leishmania donovani and Leishmania amazonensis but unexplored against Leishmania tropica. Structure of the compound was elucidated by FT-IR, mass spectrometry and multinuclear (1H and 13C) magnetic resonance spectroscopy. The compound was evaluated for its anti-leishmanial potentials against L. tropica KWH23 using in vitro anti-promastigote, DNA interaction, apoptosis, docking studies against leishmanolysin (GP63) and trypanothione reductase (TR) receptors using MOE 2016 software. ß-sitosterol exhibited significant activity against leishmania promastigotes with IC50 values of 9.2 ±â€¯0.06 µg/mL. The standard drug glucantaime showed IC50 of 5.33 ±â€¯0.07 µg/mL. Further mechanistic studies including DNA targeting and apoptosis induction via acridine orange assay exhibited promising anti-leishmanial potentials for ß-sitosterol. Molecular docking with leishmanolysin (GP63) and trypanothione reductase (TR) receptors displayed the binding scores of ß-sitosterol with targets TR and GP63 were -7.659 and -6.966 respectively. The low binding energies -61.54 (for TR) and -33.24 (for GP63) indicate that it strongly bind to the active sites of target receptors. The results confirmed that ß-sitosterol have considerable anti-leishmanial potentials and need further studies as potential natural anti-leishmanial agent against L. tropica.

Synthesis of novel N-(1,3-thiazol-2-yl)benzamide clubbed oxadiazole scaffolds: Urease inhibition, Lipinski rule and molecular docking analyses.

Present work aimed to synthesize some unique bi-heterocyclic benzamides as lead compounds for the in vitro inhibition of urease enzyme, followed by in silico studies. These targeted benzamides were synthesized in good yields through a multi-step protocol and their structures were confirmed by IR, 1H NMR, 13C NMR, EI-MS and elemental analysis. The in vitro screening results showed that most of the ligands exhibited good inhibitory potentials against the urease. Chemo-informatics analysis envisaged that all these compounds obeyed the Lipinski's rule. Molecular docking results showed that 7h exhibited good binding energy value (-8.40 kcal/mol) and was bound within the active region of urease enzyme. From the present investigation, it was inferred that some of these potent urease inhibitors might serve as novel templates in drug designing.

Synthesis, molecular docking study and thymidine phosphorylase inhibitory activity of 3-formylcoumarin derivatives.

Thymidine phosphorylase (TP) over expression plays role in several pathological conditions, such as rheumatoid arthritis, chronic inflammatory diseases, psoriasis, and tumor angiogenesis. The inhibitor of this enzyme plays an important role in preventing the serious threat due to over expression of TP. In this regard, a series of seventeenanalogs of 3-formylcoumarin (1-17) were synthesized, characterized by 1HNMR and EI-MS and screened for thymidine phosphorylaseinhibitory activity. All analogs showed a variable degree of thymidine phosphorylase inhibition with IC50 values ranging between 0.90 ±â€¯0.01 and 53.50 ±â€¯1.20 µM when compared with the standard inhibitor 7-Deazaxanthine having IC50 value 38.68 ±â€¯1.12 µM. Among the series, fifteenanalogs such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 16 and 17 showed excellent inhibition which is many folds better than the standard 7-Deazaxanthine whiletwo analogs 13 and 14 showed good inhibition. The structure activity relationship (SAR) was mainly based upon by bring about difference of substituents on phenyl ring. Molecular docking study was carried out to understand the binding interaction of the most active analogs.