Synthesis, biological evaluation, and molecular modelling of substituted thiazolyl thiourea derivatives: A new class of prolyl oligopeptidase inhibitors.

Prolyl oligopeptidase (POP) is a compelling therapeutic target associated with aging and neurodegenerative disorders due to its pivotal role in neuropeptide processing. Despite initial promise demonstrated by early-stage POP inhibitors, their progress in clinical trials has been halted at Phase I or II. This impediment has prompted the pursuit of novel inhibitors. The current study seeks to contribute to the identification of efficacious POP inhibitors through the design, synthesis, and comprehensive evaluation (both in vitro and in silico) of thiazolyl thiourea derivatives (5a-r). In vitro experimentation exhibited that the compounds displayed significant higher potency as POP inhibitors. Compound 5e demonstrated an IC50 value of 16.47 ± 0.54 µM, representing a remarkable potency. A meticulous examination of the structure-activity relationship indicated that halogen and methoxy substituents were the most efficacious. In silico investigations delved into induced fit docking, pharmacokinetics, and molecular dynamics simulations to elucidate the intricate interactions, orientation, and conformational changes of these compounds within the active site of the enzyme. Moreover, our pharmacokinetic assessments confirmed that the majority of the synthesized compounds possess attributes conducive to potential drug development.

Carbonylbis(hydrazine-1-carbothioamide) derivatives as a new class of α-glucosidase inhibitors and their mechanistic insights via molecular docking and dynamic simulations.

In the past, efforts have been made to find a cure for diabetes, mainly evaluating new classes of compounds to explore their potency. In this study, we present the synthesis and evaluation of carbonylbis(hydrazine-1-carbothioamide) derivatives as potential α-glucosidase inhibitors, employing both in vivo and in silico investigations. The in vitro experiments revealed that all tested compounds were significantly potent for α-glucosidase inhibition, with the lead compound 3a displaying approximately 80 times higher activity than acarbose. To delve deeper, in silico induced fit docking, pharmacokinetics, and molecular dynamics studies were conducted. Significantly, compound 3a exhibited a docking score of -7.87 kcal/mol, surpassing acarbose, which had a docking score of -6.59 kcal/mol. The in silico ADMET indicated that most of the synthesized compounds have properties conducive to drug development. Molecular dynamics analysis demonstrated that, when the ligand 3a was coupled with the target 3TOP, Cα-RMSD backbone RMSD values below 2.4 Å and "Lig_fit_Prot" values below 2.7 Å were observed. QSAR analysis demonstrates that the "fOC8A" descriptor positively correlates with α-glucosidase inhibition activity, while "lipoplus_AbSA" positively contributes and "notringC_notringO_8B" negatively contributes to this activity.

Synthesis, biological evaluation, and molecular docking study of xanthene-linked thiosemicarbazones as cholinesterase inhibitors.

This study delineates the design and synthesis of a series of xanthene-based thiosemicarbazones that show low µM inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), crucial enzymes associated with, among others, Alzheimer's Disease (AD) pathology. Despite FDA-approved AChE inhibitors being frontline treatments for AD, there remains a need for agents exhibiting improved efficacy and selectivity. Our synthesized series demonstrate meaningful inhibition against AChE (IC50 ranging from 4.2 to 62 µM). These compounds exhibit comparatively lower potency against BChE (IC50 values between 64 and 315 µM), showcasing a pronounced AChE selectivity compared to physostigmine. The selectivity index for the compounds between the two targets does vary between 0.02 and 0.75 highlighting that even minor structural differences can have drastic effects on protein interactions. Molecular docking insights further substantiated these observations, revealing the importance of the xanthene scaffold for AChE-binding and the aryl R2 moiety for BChE interactions. Notably, some compounds demonstrated dual enzyme targeting, emphasizing their interactions could be exploited for developing monotherapies against cholinesterase-associated neurodegenerative afflictions like AD. Collectively, these findings suggest that xanthene-based thiosemicarbazones are a promising and highly accessible scaffold that deserve further investigative exploration in the cholinesterase inhibitor therapeutic landscape.Communicated by Ramaswamy H. Sarma.

Therapeutic potential of 1,3,4-oxadiazoles as potential lead compounds for the treatment of Alzheimer's disease.

Monoamine oxidase and cholinesterase enzymes are important targets for the treatment of several neurological diseases especially depression, Parkinson disease and Alzheimer's. Here, we report the synthesis and testing of new 1,3,4-oxadiazole derivatives as novel inhibitors of monoamine oxidase enzymes (MAO-A and MAO-B) and cholinesterase enzymes (acetyl and butyryl cholinesterase (AChE, BChE). Compounds 4c, 4d, 4e, 4g, 4j, 4k, 4m, 4n displayed promising inhibitory effects on MAO-A (IC50: 0.11-3.46 µM), MAO-B (IC50: 0.80-3.08 µM) and AChE (IC50: 0.83-2.67 µM). Interestingly, compounds 4d, 4e and 4g are multitargeting MAO-A/B and AChE inhibitors. Also, Compound 4m displayed promising MAO-A inhibition with IC50 of 0.11 µM and high selectivity (∼25-fold) over MAO-B and AChE enzymes. These newly synthesized analogues represent promising hits for the development of promising lead compounds for neurological disease treatment.

Synthesis and evaluation of novel xanthene-based thiazoles as potential antidiabetic agents.

A series of xanthene-based thiazoles was synthesized and characterized by different scpectroscopic methods, i.e. Proton nuclear magnetic resonance (1 H NMR), carbon nuclear magnetic resonance (13 C NMR), infrared spectroscopy, carbon hydrogen nitrogen analysis, and X-ray crystallography. The inhibition potencies of 18 newly synthesized thiazole derivatives were investigated on the activities of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase (α-Amy), and α-glycosidase (α-Gly) enzymes in accordance with their antidiabetic and anticholinesterase ability. The synthesized compounds have the highest inhibition potential against the enzymes at low nanomolar concentrations. Among the 18 newly synthesized molecules, 3b and 3p were superior to the known commercial inhibitors of the enzymes and have a much more effective inhibitory potential, with IC50 : 2.37 and 1.07 nM for AChE, 0.98 and 0.59 nM for BChE, 56.47 and 61.34 nM for α-Gly, and 152.48 and 124.84 nM for α-Amy, respectively. Finally, the optimized 18 compounds were subjected to molecular docking to describe the interaction between thiazole derivatives and AChE, BChE, α-Amy, and α-Gly enzymes in which important interactions were monitored with amino acid residues of each target enzyme.

Exploring biologically active hybrid pharmacophore N-substituted hydrazine-carbothioamides for urease inhibition: In vitro and in silico approach.

Urease is potential target for various human's health complications, such as peptic ulcer, gastric cancer and kidney stone formation. The present study was based on synthesis of new hybrid pharmacophore N-substituted hydrazine-carbothioamides as potential urease inhibitors. Presented method gave excellent yield in range of 85-95% for hydrazine-carbothioamides derivatives (3a-s) after reaction of mono- and disubstituted hydrazides (1a-k) and substituted isothiocyanates (2a-d). All newly derivatives were characterized by advanced spectroscopic techniques (FTIR, 1HNMR, 13CNMR, EMS) and were assessed for their urease inhibition potential. All analogs except for 3k, 3l and 3m demonstrated strong inhibitory potential for urease with IC50 values of 8.45 ± 0.14 to 25.72 ± 0.23 µM as compared to standard thiourea (IC50 21.26 ± 0.35 µM). The structure-activity relationship and mode of interaction was established by molecular docking studies. It was revealed that the N-substituted hydrazine-carbothioamides interacted with nickel atoms present in the active site of urease and supported the correlations with the experimental findings. Therefore, the afforded hydrazine-carbothioamides derivatives are interesting hits for urease inhibition studies with future prospects of modification and optimization.