Synthesis of 5-(thiazol-5-yl)-4,5-dihydroisoxazoles from 3-chloropentane-2,4-dione

Synthesis, enzyme inhibition, and molecular docking studies of a novel chalcone series bearing benzothiazole scaffold

This study reports the facile synthesis of a novel series of benzothiazole-chalcones, in addition to their inhibitory profile on important metabolic enzymes including human carbonic anhydrases (hCA-I, hCA-II) and paraoxonase (PON-1). The inhibition parameters, IC₅₀ (concentration for 50% inhibition) and Ki (dissociation constant) values, toward the title enzymes were determined for the studied compounds. As a result, IC₅₀ values of hydratase activity were in the range 4.15-5.47 and 2.56-4.58 μM for hCA-I and hCA-II, respectively. At the same time, IC₅₀ values of esterase activity were in the range 24.91-104.00 and 35.25-97.00 μM, while Ki values were in the range 14.43-59.66 and 26.65-73.34 μM for hCA-I and hCA-II, respectively. In addition, PON-1 enzyme inhibition results showed interesting inhibitory effects, with IC₅₀ values between 13.28 and 16.68 μM. Finally, a comprehensive approach was established for the synthesized compounds based on theoretical calculations, which have been done using B3LYP, PBE0 theories and SVP, TVZP, TVZPP basis sets, followed by docking studies by which the outputs proved the harmonically flows with the experimental results.

2-amino thiazole derivatives as inhibitors of some metabolic enzymes: An In Vitro and In Silico study

The thiazole derivatives are desirable compounds in the evaluation of their biological activities such as antiprotozoal antibacterial, antifungal, antituberculosis. Considering the medical application potential of 2-amino thiazole compounds, we aimed to determine the effects of 2-amino thiazole derivatives on the activities of carbonic anhydrase I-II isoenzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Among the chemicals we used in our study, 2-Amino-4-(4-chlorophenyl)thiazole compound exhibited the best inhibition against hCA I with K_i of 0.008±0.001 μM. The 2-Amino-4-(4-bromophenyl)thiazole compound exhibited the best inhibition against hCA II, AChE and BChE with K_i of 0.124±0.017 μM, 0.129±0.030 μM and 0.083±0.041 μM, respectively. Molecular docking analysis showed that compound 2-Amino-4-(5,6,7,8-tetrahydro-2-naphthyl)thiazole had the highest inhibitory potency against hCA I, hCA II, AChE, BChE with the estimated binding energy of -6.75 , -7.61, -7.86, -7.96 kcal/mol, respectively. This article is protected by copyright. All rights reserved.

Structure-Based Designing, Solvent Less Synthesis of 1,2,3,4-Tetrahydropyrimidine-5-carboxylate Derivatives: A Combined In Vitro and In Silico Screening Approach

Objective: In this study, small molecules possessing tetrahydropyrimidine derivatives have been synthesized having halogenated benzyl derivatives and carboxylate linkage. As previously reported, FDA approved halogenated pyrimidine derivatives prompted us to synthesize novel compounds in order to evaluate their biological potential. Methodology: Eight pyrimidine derivatives have been synthesized from ethyl acetoacetate, secondary amine, aromatic benzaldehyde by adding catalytic amount of CuCl₂·2H₂O via solvent less Grindstone multicomponent reagent method. Molecular structure reactivity and virtual screening were performed to check their biological efficacy as an anti-oxidant, anti-cancer and anti-diabetic agent. These studies were supported by in vitro analysis and QSAR studies. Results: After combined experimental and virtual screening 5c, 5g and 5e could serve as lead compounds, having low IC₅₀ and high binding affinity.

Synthesis of new series of thiazol-(2(3H)-ylideneamino)benzenesulfonamide derivatives as carbonic anhydrase inhibitors

Human carbonic anhydrase I and II isoenzymes (hCA I and II) are important metabolic enzymes. In this study, a new series of thiazol-(2(3H)-ylideneamino)benzenesulfonamide derivatives were synthesized and also some inhibition parameters including IC50 (hydratese) and inhibition constant values (Ki , esterase) were determined. All studied compounds exhibited potent inhibition against these enzymes. They inhibited carbonic anhydrases (CAs) with the IC50 values of 113 to 395.8 nM (Ki  = 77.38-319.59 nM) for hCA I and 91.9 to 516 nM (Ki  = 62.79-425.89 nM) for hCA II. Among the compounds, 5c was found to be the most active one (Ki : 77.38 nM) for hCA I and 5g was found for hCA II with the value of 62.79 nM.

Donepezil-based multi-functional cholinesterase inhibitors for treatment of Alzheimer's disease

Alzheimer's disease (AD) is one of the most common neurodegenerative disorders in elderly people. Considering the multifactorial nature of AD, the concept of multi-target-directed ligands (MTDLs) has recently emerged as a new strategy for designing therapeutic agents on AD. MTDLs are confirmed to simultaneously affect diverse targets which contribute to etiology of AD. As the most potent approved drug, donepezil affects various events of AD, like inhibiting cholinesterases activities, anti-Aβ aggregation, anti-oxidative stress et al. Modifications of donepezil or hybrids with pharmacophores of donepezil in recent five years are summarized in this article. On the basis of case studies, our concerns and opinions about development of donepezil derivatives, designing of MTDLs, and perspectives for AD treatments are discussed in final part.

Synthesis of Some New Thiazole Derivatives and Their Biological Activity Evaluation

New 2-(4-arylpiperazine-1-yl)-N-[4-(2-(4-substituted phenyl)thiazol-4-yl)phenyl]acetamide derivatives were synthesized and evaluated for their antimicrobial and anticholinesterase activities. Acetylcholinesterase inhibitory activities of the compounds were found weak contrary to expectations. It is unlikely that antifungal activity of the compounds was found significant, especially againstCandida parapsilosis.