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Carbonic anhydrases (CAs) play an important role in maintaining pH balance by catalyzing the conversion of carbon dioxide to bicarbonate. Since this pH balance is critical to health, all organisms must develop mechanisms to control and regulate it. Although there is a great deal of literature on the biochemical, functional, and structural properties of the CA family, there is no enough knowledge on the regulation of CAs at gene and protein levels, especially their epigenetic regulation. In this study, impact of Tip60, a member of histone acetyltransferases family, on the expression of Ca1 and Ca3 genes in liver tissue was investigated at different zeitgeber time points in control and liver-specific Tip60 knockout mice (mutant) groups. First of all, Tip60 was specifically knocked out in mouse liver the using Cre/loxP system and knockout rate was shown as 83% - 88% by southern blot. Expression profiles of Ca1 and Ca3 genes in both groups were determined by Real-Time PCR at six different time points. While Ca1 showed the highest expression at ZT8 and ZT12, the lowest expression profile was observed at ZT0 and ZT20. Hepatic Ca1 showed a robust circadian expression. While hepatic Ca3 showed almost the same level of expression at different time units. The expression of Ca1 and Ca3 significantly decreased in the absence of Tip60 in mouse liver all time period. In conclusion, it was suggested for the first time that Tip60 may be considered a candidate protein in the regulation of Ca1 and Ca3 genes, possibly by acetylation.

Cancer is a disease characterized by the continuous growth of cells without adherence to the rules that healthy normal cells obey. Carbonic anhydrase I and II (CA I and CA II) inhibitors are used for the treatment of some diseases. The available drugs in the market have limitations or side effects, which bring about the need to develop new drug candidate compound(s) to overcome the problems at issue. In this study, new pyrazole-sulphonamide hybrid compounds 4-[5-(1,3-benzodioxol-5-yl)-3-aryl-4,5-dihydro-1H-pyrazol-1-yl]benzenesulphonamides (4a - 4j) were designed to discover new drug candidate compounds. The compounds 4a - 4j were synthesized and their chemical structures were confirmed using spectral techniques. The hypothesis tested was whether an introduction of methoxy and polymethoxy group(s) lead to an increased potency selectivity expression (PSE) value of the compound, which reflects cytotoxicity and selectivity of the compounds. The cytotoxicity of the compounds towards tumor cell lines were in the range of 6.7 - 400 mu M. The compounds 4i (PSE2 = 461.5) and 4g (PSE1 = 193.2) had the highest PSE values in cytotoxicity assays. Ki values of the compounds were in the range of 59.8 +/- 3.0 - 12.7 +/- 1.7 nM towards hCA I and in the range of 24.1 +/- 7.1 - 6.9 +/- 1.5 nM towards hCA II. While the compounds 4b, 4f, 4g, and 4i showed promising cytotoxic effects, the compounds 4c and 4g had the inhibitory potency towards hCA I and hCA II, respectively. These compounds can be considered as lead compounds for further research.

Chalcones are known as versatile, innovative and bioactive chemical scaffolds in drug development studies. In this study, a series of poly-methoxylated chalcones (1-8) were synthesized by Claisen-Schmidt condensation under the basic condition and their carbonic anhydrase (CA) I/II and acetylcholinesterase (AChE) inhibitory effects were firstly evaluated in this study. CA isoenzymes I and II were inhibited in nanomolar concentration with Ki values of 8.75±0.64 - 37.64±2.38 nM (hCA I) and 11.47±3.31- 45.97±4.67 nM (hCA II). The compounds inhibited the AChE enzyme in the range of 34.14±20.79 - 53.65±13.25 nM. The compounds 1, 3 and 5 were the best inhibitors against hCA I, hCA II, and AChE, respectively. The bioassay results showed that the compounds can be considered as the main frame to design novel chalcone-based enzyme inhibitors., Şalkonlar ilaç geliştirme çalışmalarında kullanışlı, yenilikçi ve biyoaktif kimyasal yapı iskeletleri olarak bilinirler. Bu çalışmada, bir dizi poli-metoksillenmiş şalkonlar (1-8) bazik koşul altında Claisen-Schmidt kondansasyonu ile sentezlendi ve karbonik anhidraz (CA) I / II ve asetilkolinesteraz (AChE) inhibitör etkileri ilk olarak bu çalışmada değerlendirildi. CA izoenzimleri olan I ve II, 8.75 ± 0.64 - 37.64 ± 2.38 nM (hCA I) ve 11.47 ± 3.31- 45.97 ± 4.67 nM (hCA II) Ki değerleri ile nanomolar konsantrasyonda inhibe edildi. Bileşikler, AChE enzimini 34.14 ± 20.79 - 53.65 ± 13.25 nM aralığında inhibe etti. Bileşik 1, 3 ve 5, sırasıyla hCA I, hCA II ve AChE'ye karşı en güçlü inhibitörlerdir. Biyolojik aktivite sonuçları, bileşiklerin yeni şalkon bazlı enzim inhibitörleri tasarlamak için ana yapı olarak kabul edilebildiğini gösterdi.Chalcones are known as versatile, innovative and bioactive chemical scaffolds in drug development studies. In this study, a series of poly-methoxylated chalcones (1-8) were synthesized by Claisen-Schmidt condensation under the basic condition and their carbonic anhydrase (CA) I/II and acetylcholinesterase (AChE) inhibitory effects were firstly evaluated in this study. CA isoenzymes I and II were inhibited in nanomolar concentration with Ki values of 8.75±0.64 - 37.64±2.38 nM (hCA I) and 11.47±3.31- 45.97±4.67 nM (hCA II). The compounds inhibited the AChE enzyme in the range of 34.14±20.79 - 53.65±13.25 nM. The compounds 1, 3 and 5 were the best inhibitors against hCA I, hCA II, and AChE, respectively. The bioassay results showed that the compounds can be considered as the main frame to design novel chalcone-based enzyme inhibitors.

N-(1-(4-Methoxyphenyl)-3-oxo-3((4-(N-(substituted)sulfamoyl)phenypamino)prop-1-en-1-yl)benzamides 3a - g were designed since sulfonamide and benzamide pharmacophores draw great attention in novel drug design due to their wide range of bioactivities including acetylcholinesterase (AChE) and human carbonic anhydrase I and II (hCA I and hCA II) inhibitory potencies. Structure elucidation of the compounds was carried out by H-1 NMR, C-13 NMR, and HRMS spectra. In vitro enzyme assays showed that the compounds had significant inhibitory potential against hCA I, hCA II, and AChE enzymes at nanomolar levels. Ki values were in the range of 4.07 +/- 0.38 - 29.70 +/- 3.18 nM for hCA I and 10.68 +/- 0.98 - 37.16 +/- 7.55 nM for hCA II while Ki values for AChE were in the range of 8.91 +/- 1.65 - 34.02 +/- 5.90 nM. The most potent inhibitors 3g (Ki = 4.07 +/- 0.38 nM, hCA I), 3c (Ki = 10.68 +/- 0.98 nM, hCA II), and 3f (Ki = 8.91 +/- 1.65 nM, AChE) can be considered as lead compounds of this study with their promising bioactivity results. Secondary sulfonamides showed promising enzyme inhibitory effects on AChE while primary sulfonamide derivative was generally effective on hCA I and hCA II isoenzymes.

In this study, three new Schiff bases have been synthesized by the reactions of commercially available phenylglycinol, phenylalaninol, and leuicinol with 4-{[2-(4-formylphenoxy)ethyl](methyl)amin}benzaldehyde and characterized by 1H and 13C NMR, FTIR, and UV-Vis spectroscopy and LCMS/MS. In vitro effects of synthesized new Schiff bases on human erythrocyte carbonic anhydrase I (hCA I) and II (hCA II) isoenzymes and acetylcholinesterase (AChE) activity were investigated. Schiff base synthesized from phenylglycinol showed no meaningful effect on hCAI and hCAII. Schiff bases synthesized from phenylalaninol and leuicinol exhibited a strong activation effect on hCAI and hCAII. On the other hand, all of the synthesized three Schiff bases exhibited a strong inhibitory effect on AChE activity.

Metal complexes of thiosemicarbazones have been receiving considerable attention in biological applications such as antimicrobial and anticancer therapies. In this work, Co(II), Zn(II) and Mn(II) complexes of 2-hydroxy-5-methoxyacetophenone thiosemicarbazone (HMAT) were synthesized for the first time and characterized by EPR, FT-IR, NMR, UV-Vis spectroscopies, TG/DSC and elemental analysis. X-ray powder diffraction analysis was carried out for Zn(II) complex. HMAT and its Cu(II), Co(II), Zn(II) and Mn(II) complexes were tested as enzyme inhibitory agents. All compounds are effective inhibitor of cytosolic carbonic anhydrase I and II isoforms (hCA I and II) enzymes. IC(50)values of HMAT and its Cu(II), Co(II), Zn(II) and Mn(II) complexes were determined as 93.35, 324.46, 25.67, 1.06 and 22.36 mu M for CA I isozyme and 99.02, 86.64, 57.76, 10.34 and 36.48 mu M for CA II isozyme, respectively. The evaluation of potential cytotoxic effects of the compounds was performed against normal epithelial breast mammary gland CRL-4010, estrogen-positive low metastatic MCF-7 and triple negative highly metastatic MDA-MB-231 breast adenocarcinoma cell lines by MTT assay. The results showed that the tested metal complexes have high cytotoxic effects than their ligand molecule. In particular, the Cu(II) complex displayed preciously high cytotoxic properties different from the others. Given these facts, the Cu(II) complex could be debated as potential chemotherapeutic molecule against drug-resistant breast cancer cells. Minimum inhibitory concentrations of the compounds against the test organisms were also detected for the microbiological analysis., Necmettin Erbakan University Scientific Research Foundation [BAP-161715001], This study was supported by the Necmettin Erbakan University Scientific Research Foundation (BAP-161715001)

Helichrysum plicatum species are used in Turkish folk medicine as lithagogue, diuretic, and nephritic. Research on the methanol (MeOH) extract of flowers of H. plicatum DC. subsp. plicatum resulted in the isolation of eight known compounds (1–8). The chemical structures of the compounds were determined as β-sitosterol (1), apigenin (2), nonacosanoic acid (3), astragalin (4), β-sitosterol-3-O-β-D-glucopyranoside (5), helichrysin A (6), helichrysin B (7), and isosalipurposide (8) by spectroscopic and chromatographic/spectrometric methods, including 1D and 2D nuclear magnetic resonance and liquid chromatography-tandem mass spectrometry. Nonacosanoic acid (3) was isolated for the first time from H. plicatum DC. subsp. plicatum. The MeOH extract and isolated compounds were evaluated for their in vitro human carbonic anhydrase I (hCAI) and II (hCAII), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glycosidase inhibitory activities. The IC50 values of H. plicatum DC. subsp. plicatum MeOH extract for hCAI, hCAII, AChE, BChE, and α-glycosidase were found to be 77.87, 52.90, 115.50, 117.46, and 81.53 mg/mL, respectively. The compounds showed IC50 values of 1.43–4.47, 1.40–4.32, 1.69–2.90, 1.09–3.89, and 1.61–3.80 μM against hCAI, hCAII, AChE, BChE, and α-glycosidase, respectively. In summary, H. plicatum DC. subsp. plicatum secondary metabolites demonstrated strong inhibitory effects especially against hCAI and hCAII, whereas the MeOH extract showed a weak inhibitory effect on all enzymes.

In this study, 22 novel compounds were designed and synthesized by acetamide bridge chains, among which 5 a-5 k were monosubstituted compounds, and 6 a-6 k were disubstituted. A series of biological evaluations was then carried out to determine the carbonic anhydrase inhibitory activity, neuroprotective effects and cytotoxicity of 5 a-5 k and 6 a-6 k. The results showed that some compounds could protect PC12 cells from sodium nitroprusside (SNP)-induced damage. In terms of the neuroprotection and inhibitory activity against carbonic anhydrase II, monosubstituted compounds were better than disubstituted. Compound 5 c exhibited better protective effect in PC12 cells than that of edaravone, and 5 c also showed less cytotoxicity. In addition, compound 5 c was found to be the most effective selective carbonic anhydrase II inhibitor (IC50 =16.7 nM, CAI/CAII=54.3), which was similar to the inhibitory effect of acetazolamide. Moreover, the selectivity of compound 5 c was better than that of acetazolamide (IC50 =12.0 nM, CAI/CAII=20.8). Molecular docking presented that the binding effect of compound 5 c with carbonic anhydrase II was superior to that of 5 c with carbonic anhydrase I and IX, which was consistent with the inhibitory results. Based on above findings, compound 5 c may be a potential candidate for selective carbonic anhydrase II inhibitor, and it had obviously neuroprotective effect and great advantages in drug safety.

WOS: 000519177800001, PubMed: 32107977, Carbonic anhydrases (CAs) are potent dehydration of carbonic acid and catalyst of the reversible hydration of carbon dioxide. Here, CA I and CA II was purified from human erythrocytes using the simple chromatographic method and determined the interactions between some calcium channel blockers and the enzymes. Molecular docking studies were performed these compounds. It was found that calcium channel blockers (nimodipine, nilvadipine, nitrendipine, isradipine, and nifedipine) exhibit potential inhibitor properties for hCA I and hCA II. IC50 values of hCA I were in the range of 9.24-58.00 mu M, and K-i constants were in the range of 7.60 +/- 2.68-35.92 +/- 16.01 mu M. IC50 values of hCA II were in the range of 70.00-138.60 mu M, and K-i constants were in the range of 48.30 +/- 9.81-162.35 +/- 20.47 mu M. Nimodipine presented the highest docking score and had competitive inhibition, the benzene and pyridine rings were found to enter the cavity for hCA I. Nifedipine and isradipine did not affect hCA II. Among these drugs, nitrendipine was found to be the most potent inhibitor for hCA I and nimodipine for hCA II. These compounds may be useful for CA inhibitors. Communicated by Ramaswamy H. Sarma

A series of amino acid–sulphonamide conjugates was prepared through benzotriazole mediated coupling reactions and characterised by 1H-NMR, 13C-NMR, MS, and FTIR spectroscopic techniques as well as elemental analysis. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was determined against four human (h) isoforms, hCA I, hCA II, hCA VA, and hCA XII. Most of the synthesised compounds showed effective in vitro CA inhibitory properties. The new amino acid–sulphonamide conjugates showed potent inhibitory activity against hCA II, some of them at subnanomolar levels, exhibiting more effective inhibitory activity compared to the standard drug acetazolamide. Some of these sulphonamides were also found to be effective inhibitors of hCA I, hCA VA, and hCA XII, with activity from the low to high nanomolar range.

In our present study, copper(II) sulfonamide complexes titled as bis-(2 acetylfuranmethanesulfonylhydrazone) copper(II) chloride, bis-(2-furaldehydemethanesulfonylhydrazone)copper(II) chloride and bis-(5-nitro-2 furaldehydemethanesulfonylhydrazone)copper(II) chloride were synthesized using aromatic sulfonylhydrazones derived from methane sulfonic acid hydrazide. The structures of copper(II) sulfonamides were determined by using LC-MS, FT-IR and UV-Vis methods, magnetism and conductivity measurements, and also electrochemical studies. In order to gain insight into the structure of the copper(II) complexes, computational studies were performed by using DFT/B3LYP/6-311G(d,p) basis set with the Gaussian 09 program package. In general, sulfonamides and their derivatives are researched for their inhibitory effects on carbonic anhydrase isoenzymes (CAs). Synthesized copper(II) complexes have also sulfonamide group which is the most important pharmacophore for CA inhibition efficiency like acetazolamide (AAZ) as positive control. The carbonic anhydrase I (CA I) inhibition of copper(II) complexes which goes on competitively was determined by using UV-Vis spectrophotometer technique, and their inhibition parameters such as K-m, IC50 and K-i were calculated. Among tested compounds, bis-(5-nitro-2 furaldehydemethanesulfonylhydrazone) copper(II) chloride was found to be the most active complex on CA I isoenzyme with IC50 value of 7.03 x 10(-5) M. The enzyme inhibition trends of copper(II) sulfonamides on CA I isoenzyme were also investigated by CV and differential pulse voltammetry (DPV) techniques, qualitatively. The substrate of p-nitrophenyl acetate (PNPA) was hydrolyzed by CA I and produced p-nitrophenol (PNP). The electrochemical studies showed that when the concentration of the inhibitor was increased, the reduction peak current of PNP produced by the hydrolysis of PNPA was decreased by enzyme inhibition.

A new zinc complex with thiosemicarbazone of glyoxylic acid (1) was synthesized with zinc acetate dihydrate and thiosemicarbazone of glyoxylic acid and crystallized in water. The absolute crystal structure of the complex was defined using the single-crystal X-ray diffraction technique. It was seen in X-ray measurements that the complex crystallized in the triclinic system with the P-1 space group. The structure of 1 represents distorted octahedral geometry around the central zinc metal. Zn(II) complex with thiosemicarbazone of glyoxylic acid was an inhibitor of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), human carbonic anhydrase I and II isoforms (hCA I and II) receptors and the inhibitor constant (Ki) values of the synthesized complex were 38.94 ± 8.2 μM for hCA I, 48.62 ± 11.3 μM for hCA II, 65.16 ± 11.4 μM for BChE and 82.04 ± 16.0 μM for AChE, respectively. The molecular docking method was used to show the complex-enzyme interactions. The pharmacokinetic properties of the complex were determined by ADME/Tox predictions and the results obtained showed that the complex could be a potential drug candidate.

A series of compounds incorporating 3-(3-(2/3/4-substituted phenyl)triaz-1-en-1-yl) benzenesulfonamide moieties were synthesised and their chemical structure was confirmed by physico-chemical methods. Carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the compounds were evaluated against human isoforms hCA I and II. KI values of these sulphonamides were in the range of 21 ± 4–72 ± 2 nM towards hCA I and in the range of 16 ± 6–40 ± 2 nM against hCA II. The 4-fluoro substituted derivative might be considered as an interesting lead due to its effective inhibitory action against both hCA I and hCA II (KIs of 21 nM), a profile rarely seen among other sulphonamide CA inhibitors, making it of interest in systems where the activity of the two cytosolic isoforms is dysregulated. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group., TYL-2019-7137, This research was supported by the Ataturk University Research Fund (Project number: TYL-2019-7137).

Ece, Abdulilah/0000-0002-3087-5145; Supuran, Claudiu/0000-0003-4262-0323 WOS: 000520863700001 PubMed: 31797703 In this study, newly synthesised compounds 6, 8, 10 and other compounds (1-5, 7 and 9) and their inhibitory properties against the human isoforms hCA I and hCA II were reported for the first time. Compounds 1-10 showed effective inhibition profiles with K-I values in the range of 5.13-16.9 nM for hCA I and of 11.77-67.39 nM against hCA II, respectively. Molecular docking studies were also performed with Glide XP to get insight into the inhibitory activity and to evaluate the binding modes of the synthesised compounds to hCA I and II. More rigorous binding energy calculations using MM-GBSA protocol which agreed well with observed activities were then performed to improve the docking scores. Results of in silico calculations showed that all compounds obey drug likeness properties. The new compounds reported here might be promising lead compounds for the development of new potent inhibitors as alternatives to classical hCA inhibitors.

New pyridine-2,6-dicarboxamide derivatives containing sulfonamide groups were synthesized by the coupling of pyridine-2,6-dicarbonyl dichloride and various aminobenzenesulfonamides in a mixture of dichloromethane and acetone. The pyridinedicarboxamide-based sulfonamides were evaluated as carbonic anhydrase (CA) and cholinesterase (ChE) inhibitors, and they showed IC50 values in the ranges 12.8-37.6 nM against human carbonic anhydrase I (hCA I), 17.8-46.7 nM against human carbonic anhydrase II (hCA II), 98.4-197.5 nM against acetylcholinesterase (AChE), and 82.2-172.7 nM against butyrylcholinesterase (BuChE). These results are comparable with those for known inhibitors such as acetazolamide (IC50 = 32.1 nM for hCA I and IC50 = 51.0 nM for hCA II) and rivastigmine (IC50 = 60.2 nM for AChE and IC50 = 14.0 nM for BuChE), which qualifies the synthesized compounds as candidates for a more in-depth study.

The structural diversity of natural products offers unique opportunities for drug discovery, but challenges associated with their isolation and screening can hinder the identification of drug-like molecules from complex natural product extracts. Here we introduce a mass spectrometry-based approach that integrates untargeted metabolomics with multistage, high-resolution native mass spectrometry to rapidly identify natural products that bind to therapeutically relevant protein targets. By directly screening crude natural product extracts containing thousands of drug-like small molecules using a single, rapid measurement, novel natural product ligands of human drug targets could be identified without fractionation. This method should significantly increase the efficiency of target-based natural product drug discovery workflows.

A series of novel N-triazolo-benzene sulfonamides-1,5-benzodiazepines 9a-d and 10d were designed and prepared through the copper-catalyzed azide alkyne cycloaddition click chemistry procedure, reacting the N1 -propargyl-1,5-benzodiazepine 2 and the N1 ,N5 -dipropargyl analog 6 with various benzene sulfonamide azides 8a-d. The synthesized compounds were found to show nanomolar affinity toward relevant isoforms of human carbonic anhydrase such as hCA I, II, IV, VII, IX, and XII. The divalent derivative 10d showed a particularly high inhibitory activity against all hCA isoforms when compared with acetazolamide, and showed potent multivalent effects, better than reported previously for divalent CA inhibitors.

The development of many severe human diseases is associated with the formation of amyloid fibrils. Most of the available information on the process of amyloid formation has been obtained from studies of small proteins and peptides, wherein the features of complex proteins’ aggregation remain insufficiently investigated. Our work aimed to research the amyloid aggregation of a large model protein, bovine carbonic anhydrase B (BCAB). It has previously been demonstrated that, when exposed to an acidic pH and elevated temperature, this protein forms amyloid fibrils. Here, we show that, under these conditions and before amyloid formation, BCAB undergoes fragmentation by acid hydrolysis to give free individual peptides and associated peptides. Fragments in associates contain a pronounced secondary structure and act as the main precursor of amyloid fibrils, wherein free peptides adopt mostly unstructured conformation and form predominantly irregular globular aggregates. Reduced acidity decreases the extent of acid hydrolysis, causing BCAB to form amorphous aggregates lacking the thioflavin T binding β-structure. The presented results provide new information on BCAB amyloid formation and show the importance of protein integrity control when working even in mildly acidic conditions.

Primary sulfonamide derivatives with various heterocycles represent the most widespread group of potential human carbonic anhydrase (hCA) inhibitors with high affinity and selectivity towards specific isozymes from the hCA family. In this work, new 4-aminomethyl- and aminoethyl-benzenesulfonamide derivatives with 1,3,5-triazine disubstituted with a pair of identical amino acids, possessing a polar (Ser, Thr, Asn, Gln) and non-polar (Ala, Tyr, Trp) side chain, have been synthesized. The optimized synthetic, purification, and isolation procedures provided several pronounced benefits such as a short reaction time (in sodium bicarbonate aqueous medium), satisfactory yields for the majority of new products (20.6–91.8%, average 60.4%), an effective, well defined semi-preparative RP-C18 liquid chromatography (LC) isolation of desired products with a high purity (&gt, 97%), as well as preservation of green chemistry principles. These newly synthesized conjugates, plus their 4-aminobenzenesulfonamide analogues prepared previously, have been investigated in in vitro inhibition studies towards hCA I, II, IV and tumor-associated isozymes IX and XII. The experimental results revealed the strongest inhibition of hCA XII with low nanomolar inhibitory constants (Kis) for the derivatives with amino acids possessing non-polar side chains (7.5–9.6 nM). Various derivatives were also promising for some other isozymes.

Four new and four known isoxazoline derivatives were synthesized from the reactions of benzonorbornadiene with nitrile oxides formed from the corresponding benzaldehydes. Three new and one known pyrazoline derivatives were also synthesized from the reactions of the benzonorbornadiene with nitrile imines formed from the corresponding compounds. The synthesized nitrogen-based novel heterocyclic compounds were evaluated against the human carbonic anhydrase isoenzymes I and II (hCA I and hCA II), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes. The synthesized nitrogen-based novel heterocyclic compounds showed IC50 values in the range of 2.69-7.01 against hCA I, 2.40-4.59 against hCA II, 0.81-1.32 mu M against AChE, and 20.83-1.70 mu M against BChE enzymes. On the contrary, nitrogen-based novel heterocyclic compounds demonstrated K-i values between 2.93 +/- 0.59-8.61 +/- 1.39 against hCA I, 2.05 +/- 0.62-4.97 +/- 0.95 against hCA II, 0.34 +/- 0.02-0.92 +/- 0.17 nM against AChE, and 0.50 +/- 0.04-1.20 +/- 0.16 mu M against BChE enzymes. The synthesized nitrogen-based novel heterocyclic compounds exhibited effective inhibition profiles against both indicated metabolic enzymes. These results may contribute to the development of new drugs particularly to treat some disorders, which are widespread in the world including glaucoma and Alzheimer's diseases.

Human carbonic anhydrase (hCA) isoenzymes are zinc ion-containing, widespread metalloenzymes and they classically play a role in pH homeostasis maintenance. CA inhibitors suppress the CA activity and their usage has been clinically established as antiglaucoma agents, antiepileptics, diuretics, and in some other disorders. Alzheimer's disease (AD) is a slowly progressive neurodegenerative disorder and a fatal disease of the brain. An advanced method to cure AD includes the strategy to design acetylcholinesterase (AChE) inhibitors. A novel series of pyrrole-3-one derivatives containing sulfa drugs (5a-i) were determined to be highly potent inhibitors for AChE and hCA I and hCA II (inhibitory constant [Ki ] values are in the range of 6.50 ± 1.02-37.46 ± 4.12 nM, 1.20 ± 0.19-44.21 ± 1.09 nM, and 8.93 ± 1.58-46.86 ± 8.41 nM for AChE, hCA I, and hCA II, respectively). The designed compounds often show a more effective inhibition than the chemicals used as the standard. Among these compounds, 5f was the most effective compound against hCA I, and compound 5e was the most effective compound against hCA II. It was determined that compound 5c was the most effective inhibitor for AChE.

New hybrid thiazolyl-pyrazoline derivatives (4a-k) were obtained through a facile and versatile synthetic procedure, and their inhibitory effects on the human carbonic anhydrase (hCA) isoforms I and II as well as on acetylcholinesterase (AChE) were determined. All new thiazolyl-pyrazolines showed activity at nanomolar levels as hCA I, hCA II, and AChE inhibitors, with KI values in the range of 13.35-63.79, 7.01-115.80, and 17.89-48.05 nM, respectively. 1-[4-(4-Cyanophenyl)thiazol-2-yl]-3-(4-piperidinophenyl)-5-(4-fluorophenyl)-2-pyrazoline (4f) and 1-(4-phenylthiazol-2-yl)-3-(4-piperidinophenyl)-5-(4-fluorophenyl)-2-pyrazoline (4a) against hCAs and 1-[4-(4-chlorophenyl)thiazol-2-yl]-3-(4-piperidinophenyl)-5-(4-fluorophenyl)-2-pyrazoline (4d) and 1-[4-(4-nitrophenyl)thiazol-2-yl]-3-(4-piperidinophenyl)-5-(4-fluorophenyl)-2-pyrazoline (4b) against AChE were identified as highly potent inhibitors, superior to the standard drugs, acetazolamide and tacrine, respectively. Compounds 4a-k were also evaluated for their cytotoxic effects on the L929 mouse fibroblast (normal) cell line. Moreover, a comprehensive ligand-receptor interaction prediction was performed using the ADME-Tox, Glide XP, and MM-GBSA modules of the Schrodinger Small-Molecule Drug Discovery Suite to elucidate the potential binding modes of the new hybrid inhibitors against these metabolic enzymes.

New derivatives were synthesised by reaction of amino-containing aromatic sulphonamides with mono-, bi-, and tricyclic anhydrides. These sulphonamides were investigated as human carbonic anhydrases (hCAs, EC 4.2.1.1) I, II, IX, and XII inhibitors. hCA I was inhibited with inhibition constants (Kis) ranging from 49 to &gt, 10,000 nM. The physiologically dominant hCA II was significantly inhibited by most of the sulphonamide with the Kis ranging between 2.4 and 4515 nM. hCA IX and hCA XII were inhibited by these sulphonamides in the range of 9.7 to 7766 nM and 14 to 316 nM, respectively. The structure–activity relationships (SAR) are rationalised with the help of molecular docking studies.

A series of some naphthol derivatives 4a-f, 5a,f, 6a, and 7a,b (six novel ones: 4c,d, 5a, 6a, 7a,b) bearing F, Cl, Br, OMe, and dioxole substituents at different positions of the aromatic rings was designed, synthesized, and characterized. The naphthol derivatives were synthesized in three steps, namely the addition reaction of furan via Diels-Alder cycloaddition reaction, copper(II) trifluoromethanesulfonate (Cu(OTf)2 )-catalyzed aromatization reaction, and the bromination reaction, respectively. The structures of the newly obtained compounds (4c,d, 5a, 6a, 7a,b) were characterized by spectroscopic techniques. In addition, some biological activity studies were investigated under in vitro conditions. Inhibition studies of these compounds were performed on human carbonic anhydrase (hCA) I and II isoenzymes purified from human erythrocytes as a biological evaluation. Moreover, their potential antioxidant and antiradical activities were studied by analytical methods like ABTS•+ and DPPH• scavenging, and it was determined that some molecules showed good activity. Also, inhibition of acetylcholinesterase (AChE), which is a marker of many degenerative neurological diseases, was tested and the results were discussed. Excellent enzyme inhibition results were recorded for most of the molecules. These 1-naphthol derivatives were found as effective inhibitors for hCA I, hCA II, and AChE with K i values ranging from 0.034 ± 0.54 to 0.724 ± 0.18 µM for hCA I, 0.172 ± 0.02 to 0.562 ± 0.21 µM for hCA II, and 0.096 ± 0.01 to 0.177 ± 0.02 µM for AChE.

In this work, the inhibitory effect of some symmetric sulfamides derived from phenethylamines were determined against human carbonic anhydrase (hCA) I, and II isoenzymes, and compared with standard compound acetazolamide. IC50 values were obtained from the Enzyme activity (%)-[Symmetric sulfamides] graphs. Also, Ki values were calculated from the Lineweaver-Burk graphs. Some symmetric sulfamides compounds (11-18) demonstrated excellent inhibition effects against hCA I, and II isoenzymes. These compounds demonstrated effective inhibitory profiles with IC50 values in ranging from 21.66-28.88 nM against hCA I, 14.44-30.13 nM against hCA II. Among these compounds, the best Ki value for hCA I (Ki : 8.34±1.60 nM) and hCA II (Ki : 16.40±1.00 nM) is compound number 11. Besides, the IC50 value of acetazolamide used as a standard was determined as hCA I, hCA II 57.75 nM, 49.50 nM, respectively. Moreover, in silico ADME-Tox study showed that all synthesized compounds (11-18) had good oral bioavailability in light of Jorgensen's rule of three, and of Lipinski's rule of five.

A series of fluoroalkylated cyclic λ3 -iodanes and their hydrochloride salts was prepared and used in a combination with sodium ascorbate in buffer or aqueous methanol mixtures for radical fluoroalkylation of a range of substituted indoles, pyrroles, tryptophan or its derivatives, and Trp residues in peptides. As demonstrated on several peptides, the aromatic amino acid residues of Trp, Tyr, Phe, and His are targeted with high selectivity to Trp. The functionalization method is biocompatible, mild, rapid, and transition-metal-free. The proteins myoglobin, ubiquitin, and human carbonic anhydrase I were also successfully functionalized.

In this study, we report the synthesis of novel tris-chalcones and testing of human carbonic anhydrase I, and II isoenzymes (hCA I, and hCA II), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and alpha-glycosidase (alpha-Gly) inhibitors for the development of novel chalcone structures towards for treatment of some diseases. The compounds demonstrated K-i values between 13.6 +/- 1.1 and 50.0 +/- 17.1 nM on hCA I, 9.9 +/- 0.8 and 39.5 +/- 15.1 nM on hCA II, 3.1 +/- 0.2 and 20.1 +/- 1.9 nM on AChE, 4.9 +/- 0.4 and 14.7 +/- 5.2 nM on BChE and 3.9 +/- 0.2 and 22.4 +/- 10.7 nM on alpha-Gly enzymes. The results revealed that novel tris-chalcones can have promising drug potential for glaucoma, leukaemia, epilepsy; Alzheimer's disease that was associated with the high enzymatic activity of hCA I, hCA II, AChE, and BChE enzymes., Erzincan Binali Yildirim University [TSA-2017-495], This work was supported by the research funds from Erzincan Binali Yildirim University [Grant Number: TSA-2017-495].

PubMed ID: 30769267 A series of substituted pyrazole compounds (1–8 and 9a, b) were synthesized and their structure was characterized by IR, NMR, and Mass analysis. These obtained novel pyrazole derivatives (1–8 and 9a, b) were emerged as effective inhibitors of the cytosolic carbonic anhydrase I and II isoforms (hCA I and II) and acetylcholinesterase (AChE) enzymes with K i values in the range of 1.03 ± 0.23–22.65 ± 5.36 µM for hCA I, 1.82 ± 0.30–27.94 ± 4.74 µM for hCA II, and 48.94 ± 9.63–116.05 ± 14.95 µM for AChE, respectively. Docking studies were performed for the most active compounds, 2 and 5, and binding mode between the compounds and the receptors were determined. © 2019

Carbonic anhydrases (CAs) play a significant function in diverse pathological and physiological processes. Their inhibitors and activators are suitable molecules to use as a drug in the treatment of different disease. In the present study, seven natural compounds, namely didymin, retusin isoquercitrin, silymarin, verbascoside, teucroside, and 3′-O-methylhypolaetin 7-O-[6′′′-O-acetyl-β-D-allopyranosyl-(1→2)]-6′′-O-acetyl-β-D-glucopyranoside were isolated from Mentha spicata, Sideritis libanotica linearis, Platanus orientalis, Teucrium chamaedrys subsp. chamaedrys, and Silybum marianum. The influences of compounds on the carbonic anhydrase I(hCAI) and II(hCAII) purified from human erythrocytes were tested. Five phenolic compounds acted as an inhibitor on the activity of hCAI, and IC50 values were computed between 18.16 and 172.5 μM. Isozyme hCAII is only inhibited by silymarin with an IC50 value of 43.12 μM. This isoenzyme was effectively activated by five natural compounds with AC50 values in the range of 2.98–18.53 μM. To understand the binding patterns of molecules that show activation effect against hCAII, molecular docking was done using Leadit 2.3.2 software, and calculated between −19.05 and −14.42 (kJ/mol) binding energies. Both in vitro and in silico results demonstrated that the best activators against hCAII were teucroside and isoquercitrin, with AC50 values of 2.98 and 3.17 μM, and binding energies −19.05 and −18.01 (kJ/mol), respectively. According to the ADME results, retusin demonstrated physicochemical and pharmacokinetic properties specific to the drug candidates.

Inhibition of Carbonic Anhydrases (CAs) has been clinically exploited for many decades for a variety of therapeutic applications. Within a research project aimed at developing novel classes of CA inhibitors (CAIs) with a proper selectivity for certain isoforms, a series of derivatives featuring the 2-substituted-benzimidazole-6-sulfonamide scaffold, conceived as frozen analogs of Schiff bases and secondary amines previously reported in the literature as CAIs, were investigated. Enzyme inhibition assays on physiologically relevant human CA I, II, IX and XII isoforms revealed a number of potent CAIs, showing promising selectivity profiles towards the transmembrane tumor-associated CA IX and XII enzymes. Computational studies were attained to clarify the structural determinants behind the activities and selectivity profiles of the novel inhibitors., Graphical Abstract

New azafluorenones, 2-aryl-4-(4-hydroxyphenyl)-5H-indeno[1,2-b]pyridin-5-ones, were prepared to evaluate their cytotoxic/anticancer properties, also their inhibitory effects on hCA I and II isoenzymes. Aryl part was changed as [phenyl (H1), 4-methylphenyl (H2), 4-methoxyphenyl (H3), 4-fluorophenyl (H4), 4-bromophenyl (H5), 4-chlorophenyl (H6), 3-hydroxyphenyl (H7), and 4-hydroxyphenyl (H8)]. The structure of the synthesized compounds was characterized by 1H NMR, 13C NMR and HRMS spectra. Cytotoxicity results of the series pointed out that the compounds H6 (PSE: 28.0) and H5 (PSE: 27.3), with the highest potency selectivity expression (PSE) value, can be considered as leader compounds of the study in designing novel anticancer agents. Additionally, all azafluorenones synthesized showed a good inhibition profile towards hCA I and II isoenzymes in the range of 54.14–73.72 nM and 67.28–76.15 nM, respectively. The compounds H5 and H6 can be considered for further designs with their cytotoxic and CA inhibitory profiles.

A new series of thirty s-triazinyl-substituted aminoalkylbenzenesulfonamides, incorporating a symmetric pair of amino acid moieties, is reported, together with inhibition studies of physiologically relevant human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms. Specifically, against the cytosolic hCA I, II, transmembrane hCA IV and the tumor-associated, membrane-bound hCA IX. The compounds were prepared by nucleophilic substitution of chlorine atoms from cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) using environmentally friendly water-based synthetic conditions. The products yields ranged in the interval of 43–97%. Purity of the products was verified by the HPLC-DAD-ESI-Q-TOF MS method. Identity of the products was confirmed by the same method plus NMR and IR. The products showed weak inhibition of the cytosolic, off-target isozyme hCA II, but some of them were low nanomolar (i.e. strong) inhibitors of the tumor-associated hCA IX. The series offered representatives selective towards isozymes hCA I, IV and IX. 2,2′-((6-((4-sulfamoylphenethyl)amino)-1,3,5-triazine-2,4-diyl)bis(imino))disuccinic acid demonstrated highest selectivity to the tumor-associated isoform hCA IX over off-target isozymes, with impressive KI ratio (hCA II/hCA IX) 213.9 and inhibition constant equal to acetazolamide (KI = 25.8 nM). Although the selectivities of some other products, e.g. those conjugating Leu and Glu, were a bit lower (188.7 and 84.3, respectively) their inhibition constants were similar to acetazolamide too (24.0 and 27.1, respectively). The selected most impressive results from the inhibition study were interpreted via molecular modeling experiment (docking in Glide) revealing different inter-molecular enzyme-substrate interaction of 2,2′-((6-((4-sulfamoylphenethyl)amino)-1,3,5-triazine-2,4-diyl)bis(imino))disuccinic acid within specific hCA IX and hCA II microregions. Therefore, several selected compounds from this study can be considered as highly effective and selective inhibitors of hCA IX, worthy to further (preclinical) investigation.

Imidazole and thiadiazole derivatives display an extensive application in pharmaceutical chemistry, and they have been investigated as bioactive molecules for medicinal chemistry purposes. Classical carbonic anhydrase (CA) inhibitors are based on sulfonamide groups, but inhibiting all CA isoforms nonspecifically, thereby causing undesired side effects, is the main drawback of these types of inhibitors. Here we reported an investigation of novel 2,6-disubstituted imidazo[2,1-b][1,3,4]thiadiazole derivatives (9a-k, 10a, and 11a) and 2,5,6-trisubstituted imidazo[2,1-b][1,3,4]thiadiazole derivatives (12a-20a) that do not possess the zinc-binding sulfonamide group for the inhibition of human carbonic anhydrase (hCA, EC 4.2.1.1) I and II isoforms and also of acetylcholinesterase (AChE, EC 3.1.1.7). Imidazo[2,1-b][1,3,4]thiadiazoles demonstrated low nanomolar inhibitory activity against hCA I, hCA II, and AChE (KIs are in the range of 23.44–105.50 nM, 10.32–104.70 nM, and 20.52–54.06 nM, respectively). Besides, compound 9b inhibit hCA I up to 18-fold compared to acetazolamide, while compound 10a has a 5-fold selectivity towards hCA II. The synthesized compounds were also evaluated for their cytotoxic effects on the L929 mouse fibroblast cell line. Molecular docking simulations were performed to elucidate these inhibitors’ potential binding modes against hCA I and II isoforms and AChE. The novel compounds reported here can represent interesting lead compounds, and the results presented here might provide further structural guidance to discover and design more potent hCA and AChE inhibitors.

A novel series of imidazothiadiazole-linked benzenesulfonamide derivatives (5a-t) was synthesized and subjected for screening against the four physiologically and pharmacologically relevant human carbonic anhydrase (hCA) isoforms: hCA I, II, VA, and IX. The compounds selectively inhibited hCA I and II over hCA VA and IX. Furthermore, among the two cytosolic isoforms, hCA II was more effectively inhibited as compared with hCA I. The most active compounds were 5o with K i = 0.246 µM and 5p with K i = 0.376 µM against hCA II, whereas compound 5f showed good inhibition against both hCA I and II with K i = 0.493 and 0.4 µM, respectively. This class of underexplored sulfonamides may be used to design isoform-selective CA inhibitors targeting enzymes of medicinal chemistry interest.

In this study, in vitro inhibition effects of (E)-1-(4-aminophenyl)-3-(aryl) prop-2-en-1-one (4-amino-chalcones) derivatives (3a–o) on acetylcholinesterase (AChE) enzyme and human erythrocyte carbonic anhydrase I and II isoenzymes (hCA I- II) were investigated. And also, the biological activities of 4-amino-chalcone derivatives against enzymes which names are acetylcholinesterase (PDB ID: 1OCE), human Carbonic Anhydrase I (PDB ID: 2CAB), human carbonic anhydrase II (PDB ID: 3DC3), were compared. After the results obtained, ADME/T analysis was performed in order to use 4-amino-chalcone derivatives as a drug in the future. Effective inhibitors of carbonic anhydrase I and II isozymes (hCAI and II) and acetylcholinesterase (AChE) enzymes with Ki values in the range of 2.55 ± 0.35–11.75 ± 3.57 nM for hCA I, 4.31 ± 0.78–17.55 ± 5.86 nM for hCA II and 96.01 ± 25.34–1411.41 ± 32.88 nM for AChE, respectively, were the 4-amino-chalcone derivatives (3a–o) molecules. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40203-021-00094-x.

Recently, carbonic anhydrase (CA, E.C.4.2.1.1) inhibitors from natural product have paved the way for novel drug design in the treatment and prevention of some global diseases such as glaucoma, diabetes, and cancer. For this purpose, the inhibition effects of oleuropein and verbascoside from olive (Olea europaea L.) oil on human carbonic anhydrase I, and II (hCA I, and II) isoenzymes were evaluated in the current study. The inhibition effects of both natural compounds were determined by the esterase activity (in vitro). IC50 value of oleuropein and verbascoside was calculated as 1.57 and 1.73 mu M for hCA I isoenzyme, respectively. At the same manner, K-i values were determined as 1.25 +/- 0.42 and 2.00 +/- 0.42 mu M, respectively. Then, IC50 value of each compound for hCA II isoenzyme was calculated as 2.23 and 1.90 mu M, respectively. Similarly, K-i values were determined as 2.37 +/- 0.87 mu M and 1.49 +/- 0.33 mu M, respectively. Also, the inhibitory effects and potent binding mechanisms of oleuropein and verbascoside on hCA I, and II isoenzymes were realized by molecular docking studies. Consequently, both natural phenolic compounds demonstrated the potent inhibition profiles against the both isoenzymes. Therefore, we believe that these results may break new ground in the drug development for the treatment of some global disorders.

A series of novel urea, sulfamide and N,N-dipropargyl substituted benzylamines were synthesized from dihydrochalcones. The synthesized compounds were evaluated for their cholinesterases and carbonic anhydrase inhibitory actions. The known dihydrochalcones were converted into four new benzylamines via reductive amination. N,N-Dipropargylamines, ureas and sulfamides were synthesized following the reactions of benzylamines with propargyl bromide, N,N-dimethyl sulfamoyl chloride and N,N-dimethyl carbamoyl chloride. The novel substituted benzylamines derived from dihydrochalcones were evaluated against some enzymes such as human erythrocyte carbonic anhydrase I and II isoenzymes (hCA I and hCA II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The novel substituted benzylamines derived from dihydrochalcones exhibited Ki values in the range of 0.121-1.007 nM on hCA I, and 0.077-0.487 nM on hCA II closely related to several pathological processes. On the other hand, Ki values were found in the range of 0.112-0.558 nM on AChE, 0.061-0.388 nM on BChE. As a result, novel substituted benzylamines derived from dihydrochalcones showed potent inhibitory profiles against indicated metabolic enzymes. In addition, Induced-Fit Docking (IFD) simulations and ADME prediction studies have also been carried out to elucidate the inhibition mechanisms and druglikeness of the synthesized compounds. Therefore, these results can make significant contributions to the treatment of some global diseases, especially Alzheimer's diseases and glaucoma, and the development of new drugs., Scientific and Technological Research Council of Turkey (TUBITAK), Turkey [112T881]; Agr Ibrahim Cecen University, Turkey [BAP: MARSL.17.001]; Ataturk University, Turkey, The authors are indebted to the Scientific and Technological Research Council of Turkey (TuBITAK, Grant No. 112T881) , Turkey;Agr Ibrahim Cecen University (BAP: MARSL.17.001) , Turkey; and Ataturk University, Turkey; for their financial support of this work.

This study contains the synthesis of N-phthalimidomethyl-substituted NHC precursors and their Ag(I) NHC coordination compounds. The NHC precursors were synthesized from the 1-(N-phthalimidomethyl)benzimidazole and alkyl/aryl halide. The Ag(I)NHC coordination compounds were synthesized from the N-phthalimidomethyl substituted benzimidazolium salts and silver oxide via the in-situ deprotonation method. The formation of all compounds was proved fully by H-1 NMR, C-13 NMR, FTIR and elemental analysis techniques. Also, these novel N-phthalimidomethyl substituted NHC precursors and Ag(I) NHC coordination compounds were found as effective inhibitors for acetylcholinesterase (AChE), human carbonic anhydrase I isoenzyme (hCA I), human carbonic anhydrase II isoenzyme (hCA II), and butyrylcholinesterase (BChE) with inhibition constants (K(i)s) in the range of 1.00 +/- 0.14-2.31 +/- 0.58 mu M for hCA I, 1.30 +/- 0.21-2.85 +/- 0.56 mu M for hCA II, 0.35 +/- 0.06-2.58 +/- 0.70 mu M for AChE, and 0.42 +/- 0.01- 1.27 +/- 0.16 mu M for BChE, respectively. (C) 2020 Elsevier Ltd. All rights reserved., Inonu University Research Fund [IUBAP-2016/124]; Inonu University Faculty of Science Department of Chemistry, This study was financially supported by Inonu University Research Fund (Project Code: IUBAP-2016/124). The authors thank the Inonu University Faculty of Science Department of Chemistry for the characterization of compounds.

Some metabolic enzyme inhibitors can be used as Multi-target-Directed-Ligands (MTDL) in Medicinal chemistry therefore, synthesis and determination of alternative inhibitors are essential. In this study, novel bis-napthoquinone derivatives (5a-o) were synthesized through a multi-component cascade reaction of two molecules of 2-hydroxy-1,4-naphthoquinone with an aromatic aldehyde in basic media using triethylamine as a catalyst. This novel heterocyclic derivatives (5a-o) are applied to inhibit the carbonic anhydrase (hCA I and hCA II) isoform in low levels of nano molecules with Ki values exist between 4.62 ± 1.01 to 70.45 ± 9.03 nM for hCA I and for hCA II which is physiologically dominant Kis values are in the range of 5.61 ± 1.04 to 73.26 ± 10.25 nM. Further these novel derivatives (5a-o) efficiently inhibit AChE with Ki values in the range of 0.13 ± 0.02 to 3.16 ± 0.56 nM. The compounds are also applied for BChE with Ki values varying between 0.50 ± 0.10 to 9.23 ± 1.15 nM. For α-glycosidase, the most efficient Ki values of 5e and 5f are 76.14 ± 9.60 and 95.27 ± 12.55 nM respectively. Finally, molecular docking calculations against enzymes (acetylcholinesterase, butyrylcholinesterase, and the human carbonic anhydrase I and II) are compared using biological activities of heterocyclic derivatives. After these calculations, an ADME/T analysis is performed to study the future medicinal use of heterocyclic derivatives from lawsone. WOS:000689510400005 34134033 Q1

In the present study, coumarin-bearing three pyridinium and three tetra-alkyl ammonium salts were synthesized. The compounds were fully characterized by 1 H- and 13 C-NMR, LC/MS and IR spectroscopic methods and elemental analyses. The cytotoxic properties of all compounds were tested against human liver cancer (HepG2), human colorectal cancer (Caco-2) and non-cancer mouse fibroblast (L-929) cell lines. Some compounds performed comparable cytotoxicity with standard drug cisplatin. Antibacterial properties of the compounds were tested against Gram-negative Escherichia coli and Gram-positive Bacillus subtilis bacteria, but the compounds did not have any antibacterial effect against both bacteria. Enzyme inhibitory properties of all compounds were tested on the activities of human carbonic anhydrase I and II, and xanthine oxidase. All compounds inhibited both enzymes more effectively than standard drugs, acetazolamide and allopurinol, respectively. The biological evaluation results showed that ionic and water soluble coumarin derivatives are promising structures for further investigations especially on enzyme inhibition field.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by dementia, memory impairment, cognitive dysfunction, and speech impairment. The utility of cholinergic replacement by acetylcholinesterase (AChE) inhibitors in AD treatment has been well documented so far. Recently, studies have also evidenced that human carbonic anhydrases (hCAs) serve as an important target for AD treatment. In this direction, the improvement of new multitarget drugs, which can simultaneously modulate several mechanisms or targets included in the AD pathway, may be a potent strategy to treat AD. In light of these data for understanding and developing AD-related multitarget AChE and hCAs inhibitors, in this study, novel methylene-aminobenzoic acid and tetrahydroisoquinolynyl-benzoic acid derivatives (4a-g and 6a-g) were designed. The synthesized analogs were experimentally validated for their effects by in vitro and direct enzymatic tests. Also, the compounds were subjected to in silico monitoring with Schrodinger Suite software to assign binding affinities of potential derivatives based on Glide XP scoring, molecular mechanics-generalized Born surface area computing, and validation by molecular docking. The results revealed that 6c (1,3-dimethyldihydropyrimidine-2,4-(1H,3H)-dione-substituted, KI value of 33.00 ± 0.29 nM), 6e (cyclohexanone-substituted, KI value of 18.78 ± 0.09 nM), and 6f (2,2-dimethyl-1,3-dioxan-4-one-substituted, KI value of 13.62 ± 0.21 nM) from the benzoic acid derivatives in this series were the most promising derivatives, as they exhibited a good multifunctional inhibition at all experimental levels and in the in silico validation against hCA I, hCA II, and AChE, respectively, for the treatment of AD.

The novel compounds with the chemical structure of N-({4-[N'-(substituted)sulfamoyl]phenyl}carbamothioyl)benzamide (1a-g) and 4-fluoro-N-({4-[N'-(substituted)sulfamoyl]phenyl}carbamothioyl)benzamide (2a-g) were synthesized as potent and selective human carbonic anhydrase (hCA) I and hCA II candidate inhibitors. The aryl part was changed to sulfacetamide, sulfaguanidine, sulfanilamide, sulfathiazole, sulfadiazine, sulfamerazine, and sulfametazine. The Ki values of compounds 1a-g were in the range of 20.73 ± 4.32 to 59.55 ± 13.07 nM (hCA I) and 5.69 ± 0.43 to 44.81 ± 1.08 nM (hCA II), whereas the Ki values of compounds 2a-g were in the range of 13.98 ± 2.57 to 75.74 ± 13.51 nM (hCA I) and 8.15 ± 1.5 to 49.86 ± 6.18 nM (hCA II). Comparing the Ki values of the final compounds and acetazolamide, compound 1c with the sulfanilamide moiety (Ki = 5.69 ± 0.43 nM, 8.8 times) and 2f with the sulfamerazine moiety (Ki = 8.15 ± 1.5 nM, 6.2 times) demonstrated promising and selective inhibitory effects against the hCA II isoenzyme, the main target protein in glaucoma. Furthermore, compounds 1d (Ki = 20.73 ± 4.32, 4 times) and 2d (Ki = 13.98 ± 2.57, 5.9 times), which have the sulfathiazole moiety, were found as potent hCA I inhibitors. Compounds 1c and 2f can be considered as the lead compounds determined in the present study, which can be investigated further to alleviate glaucoma symptoms.

Background: Phenolic Mannich bases have been reported as acetylcholinesterase (AChE) inhibitors for the medication of Alzheimer's disease. Carbonic Anhydrases (CAs) are molecular targets for anticonvulsant, diuretic and antiglaucoma drugs in the clinic. Phenolic compounds have also been mentioned as CA inhibitors. The importance of Mannich bases in drug design inspired our research group to design novel phenolic Mannic bases as potent enzyme inhibitors. Objective: In this study, novel Mannich bases, 1-(3,5-bis-aminomethyl-4-hydroxyphenyl)-3-(4- substitutedphenyl)-2-propen-1-ones (1-9), were designed to discover new and potent AChE inhibitors for the treatment of Alzheimer's disease and also to report their carbonic anhydrase inhibitory potency against the most studied hCA I and hCA II isoenzymes with the hope to find out promising enzyme inhibitors. Methods: Mannich bases were synthesized by the Mannich reaction. The structures of the compounds were elucidated by 1H NMR, 13C NMR, and HRMS. Enzyme inhibitory potency of the compounds was evaluated spectrophotometrically towards AChE, hCA I and hCA II enzymes. Results and Discussion: The compounds showed inhibition potency in nanomolar concentrations against AChE with Ki values ranging from 20.44±3.17 nM to 43.25±6.28 nM. They also showed CAs inhibition potency with Ki values in the range of 11.76±1.29-31.09±2.7 nM (hCA I) and 6.08 ± 1.18-23.12±4.26 nM (hCA II). Compounds 1 (hCA I), 5 (hCA II), and 4 (AChE) showed significant inhibitory potency against the enzymes targeted. Conclusion: Enzyme assays showed that Mannich derivatives might be considered as lead enzyme inhibitors to design more selective and potent compounds targeting enzyme-based diseases.

In the present work, we report the design and synthesis of a set of iodinated quinazolinones carrying benzenesulfonamide moiety as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The target compounds showed promising inhibitory activity against the four examined human (h) CA isoforms; I, II, IX and XII. Compounds 4-18 displayed variable inhibition constants, ranging as follows: 7.6–782.8 nM for hCA I, 34.4–412.1 nM for hCA II, 29.1–2225.3 nM for hCA IX and 8.8–429.4 nM for hCA XII. Compound 9, the most potent against the tumor-specific CA IX/CA XII (KI = 29.1 and 8.8 nM) gives the possibility to evaluate its cytotoxicity and selectivity in vitro against HepG-2, HCT-116 and MCF-7 cancer cell lines. Compound 9 showed significant cytotoxicity against the tumor cell lines (IC50 = 1.78, 1.94 and 3.07 μM, respectively) and relatively lower toxicity against WI38 normal cell line. The radiosensitizing activity of compound 9 was evaluated and displayed an increase in the radiation-induced cell death in cancer cells after receiving a single dose of 8 Gy gamma radiation. Thus, radiation was able to enhance the antiproliferative activity of compound 9. Molecular docking of 9 into the active site of CA IX and XII revealed the key interactions that could explain its potent activity and selectivity towards these isoforms.

In recent decade, the entrance of α-N-heterocyclic thiosemicarbazones derivates (Triapne, COTI-2 and DpC) in clinical trials for cancer and HIV-1 has vastly increased the interests of medicinal chemists towards this class of organic compounds. In the given study, a series of eighteen new (3a-r) 3-ethoxy salicylaldehyde-based thiosemicarbazones (TSC), bearing aryl and cycloalkyl substituents, were synthesized and assayed for their pharmacological potential against carbonic anhydrases (hCA I and hCA II), cholinesterases (AChE and BChE) and α-glycosidase. The hCA I isoform was inhibited by these novel 3-ethoxysalicylaldehyde thiosemicarbazone derivatives (3a-r) in low nanomolar levels, the Ki of which differed between 144.18 ± 26.74 and 454.92 ± 48.32 nM. Against the physiologically dominant isoform hCA II, the novel compounds demonstrated Kis varying from 110.54 ± 14.05 to 444.12 ± 36.08 nM. Also, these novel derivatives (3a-r) effectively inhibited AChE, with Ki values in the range of 385.38 ± 45.03 to 983.04 ± 104.64 nM. For BChE was obtained with Ki values in the range of 400.21 ± 35.68 to 1003.02 ± 154.27 nM. For α-glycosidase the most effective Ki values of 3l, 3n, and 3q were with Ki values of 12.85 ± 1.05, 16.03 ± 2.84, and 19.16 ± 2.66 nM, respectively. Moreover, the synthesized TCSs were simulated using force field methods whereas the binding energies of the selected compounds were estimated using MM-GBSA method. The findings indicate the present novel 3-ethoxy salicylaldehyde-based thiosemicarbazones to be excellent hits for pharmaceutical applications.

The interaction of the coordination compounds with biological molecules resulted in the investigation of the drug potential of these molecules. In this study, enzyme inhibition of DSA (1-3) coordination compounds that were previously investigated for their anticancer and antibacterial properties was investigated. Also, DSA (1-3) had Ki values of 635.30 + 152.62, 184.01 + 90.05, and 163.03 +/- 60.01 mu M against human carbonic anhydrase I, 352.23 +/- 143.09, 46.2 +/- 15.47, and 54.117 +/- 18.80 mu M against AChE, 310.64 +/- 97.35, 35.54 +/- 7.01, and 101.51 +/- 15.314 mu M against BChE, respectively. The biological activity values of these compounds against enzymes whose name are AChE, BChE, and hCAI were compared. Ellman and Verporte methods were used for the study of these enzymes. Cholinesterase inhibitors, also known as anti-cholinesterase and cholinesterase blocking drugs, are chemicals that prevent the breakdown of the neurotransmitter acetylcholine or butyr-ylcholine. They may be used as drugs for Alzheimer's and myasthenia gravis. It is a common method for com-paring biological activity values of nickel complexes with molecular docking calculations. Nickel complexes were studied against enzymes that are human carbonic anhydrase isozyme I for ID 2CAB (hCA I), butyr-ylcholinesterase for ID 1P0I (BChE), and acetylcholinesterase for ID 1EEA (AChE), respectively.

In this study, a novel silver N-heterocyclic carbene (Ag-NHC) complex bearing hydroxyethyl substituent has been synthesized from the hydroxyethyl-substituted benzimidazolium salt and silver oxide by using in-situ deprotonation method. A structure of the Ag-NHC complex was characterized by using UV-Vis, FTIR, 1H-NMR and 13C-NMR spectroscopies and elemental analysis techniques. Also, the crystal structure of the novel complex was determined by single-crystal X-ray diffraction method. In this paper, compound 1 showed excellent inhibitory effects against some metabolic enzymes. This complex had Ki of 1.14 0.26 &micro, M against human carbonic anhydrase I (hCA I), 1.88&plusmn, 0.20 &micro, M against human carbonic anhydrase II (hCA I), and 10.75&plusmn, 2.47 &micro, M against &alpha, glycosidase, respectively. On the other hand, the Ki value was found as 25.32&plusmn, 3.76 &micro, M against acetylcholinesterase (AChE) and 41.31&plusmn, 7.42 &micro, M against butyrylcholinesterase (BChE), respectively. These results showed that the complex had drug potency against some diseases related to using metabolic enzymes.

l-Carnosine (&beta, Ala-l-His) and several other histidine-containing peptides, including two N-methylated forms on the imidazole ring (l-anserine and l-balenine), two derivatives modified on the carboxyl function (carcinine and l-carnosinamide), two analogues differing in the length of the N-terminal residue (l-homocarnosine and Gly-l-His) and the N-acetyl derivatives, were investigated as activators of four isoforms of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1). The four human isoforms hCA I, II, VA and IX were activated in the low to high micromolar range, with a rather complex structure activity relationship. A performed computational study allowed us to rationalize these results and to propose a binding mode of these activators within the enzyme active site. Similarly to other CA activators, the here studied peptides could find relevant pharmacological applications such as in the management of CA deficiencies, for therapy memory and enhancing cognition or for artificial tissues engineering.

Background Thiophene(s) are an important group in therapeutic applications, and sulfonamides are the most important class of carbonic anhydrase (CA) inhibitors. In this study, inhibition effects of some thiophene-based sulfonamides on human erythrocytes carbonic anhydrase I and II isoenzymes (hCA-I and hCA-II) were investigated. Thiophene-based sulfonamides used in this study showed potent inhibition effect on both isoenzymes at very small concentrations. Materials and methods We report on the purification of the carbonic anhydrase I and II isoenzymes (hCA-I and hCA-II) using affinity chromatography method. The inhibition effect of the thiophene-based sulfonamides was determined by IC(50)and K(i)parameters. A molecular docking study was performed for each molecule. Results Thiophene-based sulfonamides showed IC(50)values of in the range of 69 nM to 70 mu M against hCA-I, 23.4 nM to 1.405 mu M against hCA-II. K(i)values were in the range of 66.49 +/- 17.15 nM to 234.99 +/- 15.44 mu M against hCA-I, 74.88 +/- 20.65 nM to 38.04 +/- 12.97 mu M against hCA-II. Thiophene-based sulfonamides studied in this research showed noncompetitive inhibitory properties on both isoenzymes. To elucidate the mechanism of inhibition, a molecular docking study was performed for molecules 1 and 4 exhibiting a strong inhibitory effect on hCA-I and hCA-II. The compounds inhibit the enzymes by interacting out of catalytic active site. The sulfonamide and thiophene moiety played a significant role in the inhibition of the enzymes. Conclusion We hope that this study will contribute to the design of novel thiophene-based sulfonamide derived therapeutic agents that may be carbonic anhydrase inhibitors in inhibitor design studies.