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Sulfonamides represent an important class of biologically active compounds. A sulfonamide possessing carbonic anhydrase (CA) inhibitory properties obtained from a pyrazole based sulfonamide, ethyl 1-(3-nitrophenyl)-5-phenyl-3-((5-sulfamoyl-1,3,4-thiadiazol-2-yl)carbamoyl)-1H-pyrazole-4-carboxylate (1), and its metal complexes with the Ni(II) for (2), Cu(II) for (3) and Zn(II) for (4) have been synthesized. The structures of metal complexes (2–4) were established on the basis of their elemental analysis, 1H NMR, IR, UV–Vis and MS spectral data. The inhibition of two human carbonic anhydrase (hCA, EC 4.2.1.1) isoenzymes I and II, with 1 and synthesized complexes (2–4) and acetazolamide (AAZ) as a control compound was investigated in vitro by using the hydratase and esterase assays. The complexes 2, 3 and 4 showed inhibition constant in the range 0.1460–0.3930 µM for hCA-I and 0.0740–0.0980 µM for hCA-II, and they had effective more inhibitory activity on hCA-I and hCA-II than corresponding free ligand 1 and than AAZ. © 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group., This work was supported by Scientific and Technological Research Council of Turkey (TUB€ İTAK) with Grant No. TBAG-104T406.

WOS: 000440125700023, 2-Amino-6-sulfamoylbenzothiazole (SMABT) and its proton transfer compound (HSMABT)(+)(HDPC)(-) (1) with 2,6-pyridinedicarboxylic acid (H2DPC), and their Cu(II) complexes (2 of SMABT, 3 and 4 of 1) have been prepared and characterized by spectroscopic techniques. Additionally, single crystal X-ray diffraction techniques were applied to all complexes. All compounds, including acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibition effects on human hCA I and hCA II for their hydratase and esterase activities. The synthesized complexes have remarkable inhibitory effects on hCA I and hCA II isoenzymes. The inhibition potentials of the proton transfer salt (1) and the metal complexes (2-4) are comparable with AAZ. Esterase K-i values of the compounds (1-4) are in the range of 0.089 +/- 0.008 mu M-0.149 +/- 0.017 mu M for hCA I and 0.046 +/- 0.008 mu M-0.085 +/- 0.019 mu M for hCA II. Inhibition data have been analyzed by using a one-way analysis of variance for multiple comparisons (p < 0.0001). (C) 2018 Published by Elsevier Ltd., Dumlupinar University Research Fund [2014/18]; Aksaray University of Science and Technology Application and Research Center [2010K120480], The authors acknowledge the support provided by Dumlupinar University Research Fund (grant No. 2014/18). In addition, the authors acknowledge Aksaray University of Science and Technology Application and Research Center, for the use of the Bruker SMART BREEZE CCD diffractometer (purchased under grant No. 2010K120480 of the State of Planning Organization).

Bu calismada, ilk olarak 3-aminobenzensulfonilamit (abs) ile maleik anhidritin (mal) tepkimesinden ( E )-4-okso-4-(3-sulfamoyilfenil )amino)but-2-enoik asit (H m absmal) bilesigi sentezlenmistir. Daha sonra H m absmal bilesigi ile 2-aminopiridinin (ap) proton transfer tuzu ( 1 ) hazirlanmistir. Bu maddelerin degisik yontemlerle Co(II) ( 2 ) ve Cu(II) ( 3 ve 4 ) gecis metal kompleksleri sentezlenmistir. Proton transfer tuzunun yapisi elementel analiz, 1 H-NMR, 13 C-NMR , FT-IR, UV-Vis metotlari ile aydinlatilmistir. Amorf halde elde edilen gecis metal komplekslerinin yapilari ise elementel analiz, ICP-OES, FT-IR, UV-Vis, termal analiz, manyetik duyarlilik ve molar iletkenlik sonuclari dikkate alinarak onerilmistir. Ayrica, sentezlenen maddelerin insan eritrosit hCA I ve hCA II izoenzimleri uzerindeki inhibisyon etkilerini belirlemek uzere in vitro calismalar yapilmistir. Yeni sentezlenen maddelerin izoenzimlerin esteraz aktivitesini inhibe ettigi, hidrataz aktivitesini ise sadece 3 bilesiginin inhibe ettigi tespit edilmistir. Bu maddelerin inhibisyon degerlerinin kontrol bilesigi asetazolamid (AAZ) degerleri ile kiyaslanabilir buyuklukte oldugu tespit edilmistir. In this study, firstly (E)-4-oxo-4-(3-sulfamoylphenylamino)but-2-enoic acid (H m absmal) has been synthesized from the reaction between 3‑aminobenzenesulfonamide (abs) and maleic anhydride (mal) and secondly, proton transfer salt has been prepared from 2-aminopyridine (ap) and H m absmal. Transition metal complexes of these substances, Co(II) ( 2 ) and Cu(II) ( 3 and 4 ), have been synthesized by different methods . The structure of proton transfer compounds have been proposed by using elemantal analysis, 1 H-NMR, 13 C-NMR, UV-Vis techniques. The structure of amorphous metal complexes have been proposed by using elemantal analysis, ICP-OES, FT-IR, UV-Vis, thermal analysis, magnetic susceptibility and molar conductivity techniques. In addition, in vitro studies have been performed to determine the inhibition effects of synthesized compounds on human erythrocyte hCA I and hCA II isoenzymes. It has been observed that synthesized compounds have affected esterase activities of hCA I and hCA II. But only compound 3 has inhibiton effect on the hydratase activities on the isozymes. Also the inhibition values of these compounds are comparable with the inhibition values of control compound acetazolamide (AAZ).

WOS: 000392591100016, PubMed: 28100079, A novel proton transfer compound (SMHABT) (+)(HDPC)(-) (1) obtained from 2-amino-6-sulfamoylbenzothiazole (SMABT) and 2,6-pyridinedicarboxylic acid (H2DPC) and its Fe(III), Co(II), Ni(II) complexes (2-4), and Fe(II) complex of SMABT (5) have been prepared and characterized by spectroscopic techniques. Additionally, single crystal X-ray diffraction techniques were applied to complexes (2-4). All complexes (2-4) have distorted octahedral conformations and the structure of 5 might be proposed as octahedral according to spectral and analytical results. All compounds, including acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibition effects on human hCA I and hCA II for their hydratase and esterase activities. The synthesized compounds have remarkable inhibitory activities on hCA I and hCA II. Especially, the inhibition potentials of the salt and the metal complexes (1-5) are comparable with AAZ. Inhibition data have been analyzed by using a one-way analysis of variance for multiple comparisons (p < .0001)., Dumlupinar University Research Fund [2014/18], This work was supported by the Dumlupinar University Research Fund [(grant No. 2014/18)].

WOS: 000352274500004, PubMed ID: 24758349, A novel proton transfer compound (HClABT)(+)(HDPC.H2DPC)(-) (1) and its Fe(III), Co(II), Ni(II) and two different Cu(II) complexes (2-6) have been prepared and characterized by spectroscopic techniques. Additionally, single crystal X-ray diffraction techniques were applied to all complexes. All compounds, including acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibition effects on human hCA I and hCA II for their hydratase and esterase activities. Although there is no inhibition for hydratase activities, all compounds have inhibited the esterase activities of hCA I and II. The comparison of the inhibition studies of 1-6 to parent compounds, ClABT and H2DPC, indicates that 1-6 have superior inhibitory effects. The inhibition effects of 2-6 are also compared to the inhibitory properties of the simple metal complexes of ClABT and H2DPC, revealing an improved transfection profile. Data have been analysed by using a one-way analysis of variance for multiple comparisons., Dumlupynar University Research Fund [2012/16], The authors acknowledge the support provided by Dumlupynar University Research Fund (grant No. 2012/16).

Reaction of dimedone, 4-amino-N-(diaminomethylene)benzenesulfonamide, and aromatic aldehydes was successfully realized using sulfuric acid as a cheap catalyst. Synthesis of novel acridine sulfonamide compounds was performed providing high yields in water as the solvent at room temperature. This method has several advantages such as use of a green solvent, high yields, and efficient one-pot procedure. In addition, human carbonic anhydrase isoenzymes (hCA I and hCA II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of acetazolamide and the newly synthesized acridine sulfonamides on hydratase and esterase activities of these isoenzymes was studied in vitro. The esterase IC 50 values of the new compounds are 47.2-230.1 µM for hCA I and 50.1-275.0 µM for hCA II. Graphical abstract: [Figure not available: see fulltext.] © 2014 Springer-Verlag Wien.

Novel sulfonamide derivatives 6a–i, as new carbonic anhydrase inhibitors which candidate for glaucoma treatment, were synthesized from the reactions of 4-amino-N-(4-sulfamoylphenyl) benzamide 4 and sulfonyl chloride derivatives 5a–i with high yield (71–90%). The structures of these compounds were confirmed by using spectral analysis (FT-IR, 1H NMR, 13C NMR, LC/MS and HRMS). The inhibition effects of 6a–i on the hydratase and esterase activities of human carbonic anhydrase isoenzymes, hCA I and II, which were purified from human erythrocytes with Sepharose®4B-l-tyrosine-p-aminobenzene sulfonamide affinity chromatography, were studied as in vitro, and IC50 and Ki values were determined. The results show that newly synthesized compounds have quite powerful inhibitory properties.

Kinetic behavior and some properties of carbonic anhydrase enzyme purified from gills of rainbow trout (Oncorhynchus mykiss) were studied at 4C. The purification steps included high-speed centrifugation, sepharose-4B-L tyrosine-sulfanilamide affinity gel chromatography and dialysis. Yield and specific activity of the enzyme were 40% and 55.56 EU / mg protein, respectively. The overall purification was 104.8-fold. The molecular mass was approximately estimated as 28 kDa by SDS polyacrylamide gel electrophoresis and as 27 kDa by gel filtration column chromatography. Optimal pH, stable pH and optimal temperature of the enzyme were 9.5, 8.2 in 0.025 M boric acid buffer and 17.5C, respectively. K-M and V-max values of the enzyme for the substrate (p-nitrophenylacetate) were 8.13 mM and 2.10 mu mol / mg protein / min, respectively. The dissociation constant of the enzyme inhibitor complex (K-i) value was 3.93 +/- 0.65 mu M for sulfanilamide and sulfanilamide inhibited the enzyme in a noncompetitive manner. Data from present study showed that optimum kinetic properties of gill CA enzyme were different from other vertebrate CA's.

WOS: 000342056900013, PubMed ID: 24148087, A novel proton transfer compound (HMeOABT) (+) (HDPC)(-) (1) and its Fe(III), Co(II), Ni(II) and Cu(II) complexes (2-5) have been prepared and characterized by spectroscopic techniques. Complex 4 has distorted octahedral conformation revealed by single crystal X-ray diffraction method. Structures of the other complexes might be proposed as octahedral according to experimental data. All compounds were also evaluated for their in vitro inhibition effects on hCA I and II for their hydratase and esterase activities. Although there is no inhibition for hydratase activities, all compounds have inhibited the esterase activities of hCA I and II. Data have been analyzed by using a one-way analysis of variance. The comparison of the inhibition studies of 1-5 to parent compounds indicates that 1-5 have superior inhibitory effects. The inhibition effects of 2-5 are also compared to inhibitory properties of the metal complexes of MeOABT and H2DPC, revealing an improved transfection profile., Dumlupinar University Research Fund [2012/16], The authors acknowledge the support provided by Dumlupinar University Research Fund (grant No. 2012/16). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

WOS: 000322938100008, A novel proton transfer compound (HMeABT)(+)(HDPC)(-)center dot H2O (1) obtained from 2-amino-6-methylbenzothiazole (MeABT) and dipicolinic acid (H2DPC) and its Fe(III), Fe(II), Co(II), Ni(II) and Cu(II) complexes (2-6) have been prepared and characterized by elemental, spectral (H-1 NMR, IR and UV-Vis) and thermal analyses, magnetic measurement and molar conductivity. Additionally, single crystal X-ray diffraction techniques were applied to all complexes. All compounds, including acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibition effects on human carbonic anhydrase isoenzymes (hCA I and hCA II) for their hydratase and esterase activities. Although there is no inhibition for hydratase activities, all compounds have inhibited the esterase activities of hCA land II. The comparison of the inhibition studies of 1-6 to parent compounds, MeABT and H2DPC, indicates that 1-6 have more inhibitory effects. The inhibition effects of 2-6 are also compared to the simple metal complexes of MeABT and H2DPC, and the complexes from proton transfer salt (2-6) have shown better inhibition effects. Nevertheless, all the studied compounds have less inhibition effects than AAZ, Dumlupinar University Research Fund [2010/2], The authors acknowledge the support provided by Dumlupinar University Research Fund (grant No. 2010/2). In addition, the authors would like to thank the Medicinal Plants and Medicine Research Center of Anadolu University Eskisehir for allowing to use the X-ray facility.

4-Amino-N-(4-sulfamoylphenyl)benzamide was synthesized by reduction of 4-nitro-N-(4-sulfamoylphenyl)benzamide and used to synthesize novel acridine sulfonamide compounds, by a coupling reaction with cyclic-1,3-diketones and aromatic aldehydes. The new compounds were investigated as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), and more precisely the cytosolic isoforms hCA I, II and VII. hCA I was inhibited in the micromolar range by the new compounds (KIs of 0.16-9.64 µM) whereas hCA II and VII showed higher affinity for these compounds, with KIs in the range of 15-96 nM for hCA II, and of 4-498 nM for hCA VII. The structure-activity relationships for the inhibition of these isoforms with the acridine-sulfonamides reported here were also elucidated. © 2013 Elsevier Ltd. All rights reserved.

Objectives Two new metal complexes, diaquabis(4-benzoyl-1,5-diphenyl-N-(5-sulfamoyl-1,3,4-thiadiazol-2-yl)-1H-pyrazole-3-carboxamide)cobalt(II) dihydrate (2) and diaquabis(ethyl-1-(3-nitrophenyl)-5-phenyl-3-(5-sulfamoyl-1,3,4-thiadiazol-2-ylcarbamoyl)-1H-pyrazole-4-carboxylate)cobalt(II) monohydrate (4), containing sulfonamide have been synthesized by the reaction of Co(II) with 4-benzoyl-1,5-diphenyl-N-(5-sulfamoyl-1,3,4-thiadiazol-2-yl)-1H-pyrazole-3-carboxamide (1) and ethyl-1-(3-nitrophenyl)-5-phenyl-3-(5-sulfamoyl-1,3,4-thiadiazol-2-ylcarbamoyl)-1H-pyrazole-4-carboxylate (3), respectively. Methods The structures of Co(II) complexes 2 and 4 have been characterised by spectroscopic methods and elemental analyses. Human carbonic anhydrase isoenzymes (hCA-I and hCA-II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of ligands 3 and 4, acetazolamide as a control compound and the newly synthesized complexes on the activity of hydratase and esterase of these isoenzymes have been studied in vitro. Key findings The concentration of compounds 2 and 4 producing a 50% inhibition of hydratase activity (IC50 values) were 0.473 ± 0.025 and 0.065 ± 0.002 μm for hCA-I and 0.213 ± 0.015 and 0.833 ± 0.021 μm for hCA-II, respectively. The IC50 values of synthesized compounds 2 and 4 for esterase activity were, 0.058 ± 0.006 and 0.297 ± 0.015 μm for hCA-I and 0.110 ± 0.010 and 0.052 ± 0.002 μm for hCA-II, respectively. In relation to esterase activity, the inhibition equilibrium constants (Ki) were determined as 0.039 ± 0.004 and 0.247 ± 0.035 μm on hCA-I and 0.078 ± 0.002 and 0.363 ± 0.015 μm on hCA-II for 2 and 4, respectively. Conclusions The synthesized compounds 2 and 4 had effective inhibitory activity (P < 0.0001) on hCA-I and hCA-II than the corresponding free ligands, 1 and 3, and acetazolamide. Compounds 2 and 4 might be considered as potential inhibitors.

Novel dioxoacridine sulfonamide compounds were synthesized from reaction of cyclic 1,3-diketones, sulfanilamide (4-amino benzene sulfonamide) and aromatic aldehydes. The structures of these compounds were confirmed by using spectral analysis (IR, H-NMR, 13C-NMR, and mass). Human carbonic anhydrase isoenzymes (hCA I and hCA II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of sulfanilamide, acetazolamide (AAZ), and newly synthesized sulfonamides on hydratase and esterase activities of these isoenzymes have been studied in vitro. The IC50 values of compounds for esterase activity are 0.710.11 M for hCA I and 0.450.12 M for hCA II, respectively. The Ki values of these inhibitors were determined as 0,380,008 M for hCA I and 0,190,001 M for hCA II, respectively. © 2012 Informa UK, Ltd., Fundamental Research Fund of Shandong University: 2008-4, The authors are very grateful to Dumlupinar University Research Fund for providing financial support for this project (Grant No. 2008-4).

Three novel metal complexes of N-[5-(aminosulfonyl)-1,3,4-thiadiazol-2-yl]-4-benzoyl-1-(3-nitrophenyl)-5-phenyl-1H-pyrazole-3-carboxamide which possess strong carbonic anhydrase (CA) inhibitory properties have been synthesised. The structure of these compounds has been investigated by elemental analysis, FT-IR, LC/MS, UV-vis spectrophotometric method and magnetic susceptibility. Human carbonic anhydrase isoenzymes hCA-I and hCA-II were purified from erythrocyte cells by the affinity chromatography. The inhibitory effects of newly synthesized complexes and acetazolamide (AAZ) as a control compound on hydratase and esterase activities of these isoenzymes have been studied in vitro by comparing IC50 and Ki values and it has been found that the newly synthesised complexes behave as very powerful inhibitors against hCA-I and hCA-II than parent ligand (1) and than AAZ. © 2013 Informa UK, Ltd., National Council for Scientific Research, This work was supported by The Scientific and Research Council of Turkey (TÜBİTAK) with Grant No. TBAG-104T406.

A proton transfer compound, (Hamp)+(Hdipic)- 1.5H2O (1), and Cu(II) complexes, Cu(dipic)(amp)(H2O)] . [Cu(dipic)(amp)] . H2O.CH3COOH (2) and [Cu(dipic)(amp)Cu(dipic) (amp)(H2O)Cu(dipic)(amp)(H2O)] .3H2O (3), have been synthesized from 2,6-pyridinedicarboxylic acid (H2dipic) and 2-amino-4-methylpyridine (amp). They have been characterized by elemental, spectral (1H-NMR, IR, and UV-Vis), and thermal analyses. In addition, magnetic measurements and single crystal X-ray diffraction have been applied to 2 and 3. The crystal structure of 2 consists of two independent and different cationic sites with Cu2+ ions. Cu1 is four-coordinate in a distorted square planar geometry and Cu2 is five-coordinate in a distorted square pyramid. Compound 3 has three independent and different cationic sites of Cu2+ ions. Cu1 is four-coordinate in a distorted square planar geometry and Cu2 and Cu3 have fivecoordinate, distorted square-pyramidal sites. Inhibitory effects of 1, 2, and 3 have been studied and compared with starting compounds (amp and H2dipic) on bacterial growth of Staphylococcus aureus and Escherichia coli cultures. Compounds 2 and 3 prevent bacterial growth although 1 has no effect. Compounds 2 and 3 are more effective than amp and H2dipic, at similar concentrations on preventing bacterial growth for both organisms. © 2011 Taylor & Francis., Fundamental Research Fund of Shandong University Faculty of Arts and Sciences Ondokuz Mayis Üniversitesi 2007/2, The authors gratefully acknowledge the support provided by Dumlup|nar University, Turkey (under grant no. 2007/2 of the University Research Fund). The also thank the Faculty of Arts and Sciences, Ondokuz Mayis University, Turkey, for using the Stoe IPDS-2 diffractometer purchased under grant F.279 of the University Research Fund.

Pyrazole carboxylic acid derivatives of 5-amino-1,3,4-thiadiazole-2- sulfonamide (inhibitor 1) were synthesized from ethyl 3-(chlorocarbonyl)-1-(3- nitrophenyl)-5-phenyl-1H-pyrazole-4-carboxylate compound. The inhibitory effects of inhibitor 1, acetazolamide (AAZ) and of 11 newly synthesized amides (5a-b, 6, 7a-g, and 8) on hydratase and esterase activities of carbonic anhydrase isoenzymes (hCA-I and hCA-II) have been studied in vitro. The comparison of newly synthesized amides to inhibitor 1 and to AAZ indicated that the new derivatives inhibit CA isoenzymes and they are more potent inhibitors than the parent inhibitor 1 and AAZ. © 2010 Elsevier Masson SAS. All rights reserved., Türkiye Bilimsel ve Teknolojik Araştirma Kurumu: 106T180 National Council for Scientific Research, This study was funded by The Scientific and Research Council of Turkey (TÜBITAK) with Grant No 106T180 .

Pyrazole carboxylic acid amides of 5-amino-1,3,4-thiadiazole-2-sulfonamide 1 (inhibitor 1) were synthesized from 4-benzoyl-1-(4-nitrophenyl)-5-phenyl-1H-pyrazole-3-carbonyl chloride and 4-benzoyl-1-(3-nitrophenyl)-5-phenyl-1H-pyrazole-3-carbonyl chloride compounds. Human carbonic anhydrase isoenzymes (hCA-I and hCA-II) were purified from erythrocyte cells by the affinity chromatography. The inhibitory effects of inhibitor 1, acetazolamide (AAZ), and of 16 newly synthesized amides (8-11, 12a-f, 13a-c, 14a-b, and 15) on hydratase and esterase activities of these isoenzymes have been studied in vitro. The average IC50 values of the new compounds (8-11, 12a-f, 13a-c, 14a-b, and 15) for hydratase activity ranged from 3.25 to 4.75 µM for hCA-I and from 0.055 to 2.6 µM for hCA-II. The mean IC50 values of the same inhibitors for esterase activity were in the range of 2.7-6.6 µM for hCA-I (with the exception of inhibitor 10, which did not inhibit the esterase activity of hCA-I) and of 0.013-4.2 µM for hCA-II. The Ki values for new compounds (8-11, 12a-f, 13a-c, 14a-b, and 15) were observed well below that of the parent compound inhibitor 1 and were also comparable to that of AAZ under the same experimental conditions. The comparison of newly synthesized amides to inhibitor 1 and to AAZ indicated that the new derivatives preferentially inhibit hCA-II and are more potent inhibitors of hCA-II than the parent inhibitor 1 and AAZ. © 2009 Elsevier Ltd. All rights reserved., Türkiye Bilimsel ve Teknolojik Araştirma Kurumu National Council for Scientific Research, This study was funded by The Scientific and Research Council of Turkey (TÜBITAK) with Grant No. TBAG-2376 and 106T180.

Previous studies have shown that generation of free radicals is increased following pentylenetetrazol kindling, due to increased cytosolic Ca2+ concentrations. Topiramate, a voltage-gated calcium channel inhibitor, has an evident effect in the treatment of childhood epilepsy; however, topiramate may cause nephrotoxicity. We investigated the effects of topiramate and vitamin E administration on pentylenetetrazol-induced nephrotoxicity in rats by evaluation of lipid peroxidation, nitric oxide, glutathione peroxidase, catalase and superoxide dismutase values. Forty male Wistar rats were randomly divided into five equal groups. Group 1 was used as control and group II received a single dose of pentylenetetrazol. Fifty and 100 mg/kg topiramate daily were intragastrically administered to rats in groups III and IV for 7 days, respectively. Intragastric 100 mg topiramate (daily for 7 days) and intraperitoneal vitamin E (150 mg/kg, daily for 3 days) combination were given to animals in group V before a single-dose pentylenetetrazol administration. Serum and kidney samples were taken after 3 hr of pentylenetetrazol administration. Pentylenetetrazol resulted in a significant increase in nitric oxide levels of serum and kidney, and lipid peroxidation levels of kidney although superoxide dismutase and catalase activities in the kidney was reduced by pentylenetetrazol administration. The lipid peroxidation levels in serum and kidneys and the nitric oxide levels in kidneys of groups III, IV and V were decreased by topiramate although the superoxide dismutase and catalase activities in the kidneys were increased. Lipid peroxidation and nitric oxide levels were reduced by the topiramate and vitamin E combination compared to only topiramate. Glutathione peroxidase activity was not affect by pentylenetetrazol, topiramate and vitamin E administrations. In conclusion, topiramate and vitamin E have protective effects on pentylenetetrazol-induced nephrotoxicity by inhibition of free radicals and by support of the antioxidant redox system. © 2008 The Authors.

WOS: 000260847500020, PubMed: 18618324, Pyrazole carboxylic acid amides of 5-amino-1,3,4-thiadiazole-2-sulfonamide were synthesized from 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonyl chloride and 4-benzoyl-1-(3-nitrophenyl)-5-phenyl-1H-pyrazole-3-carbonyl chloride. Carbonic anhydrase isoenzymes (hCA-I and hCA-II) were purified from human erythrocyte cells by the affinity chromatography method. The inhibitory effects of 5-amino-1,3,4-thiadiazole-2-sulfonamide 1, acetazolamide 2 and new synthesized amides on these isozymes have been studied in vitro. The I50 concentrations (the concentration of inhibitor producing a 50% inhibition of CA activity) against hydratase activity ranged from 1.2 to 2.2nM for hCA-I and from 0.4 to 2nM for hCA-II. The I50 values against esterase activity ranged from 1.4 to 8nM for hCA-I and from 1.3 to 6nM for hCA-II. The Ki values were observed between 8.210-5 to 6.210-4 M for hCA-I and between 2.910-4 to 8.210-4 M for hCA-II. The comparison of new synthesized amides to 5-amino-1,3,4-thiadiazole-2-sulfonamide 1, acetazolamide 2 indicated that the new synthesized compounds (18-23) inhibit CA activity more potently than the parent compounds., TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [TBAG- 2376], This research was funded by TUBITAK (The Foundation of Scientific and Technological Research of Turkey, TBAG- 2376) (Ankara/ Turkey).

In this study, the in vitro effects of some sulfonamide derivatives, which are carbonic anhydrase inhibitors, on the enzymes activities of glucose-6-phosphate dehydrogenase, 6-phospho gluconate dehydrogenase and glutathione reductase were investigated. For this purpose, these three enzymes were purified from human erythrocytes. Purification procedure composed of four steps; preparation of the hemolysate, ammonium sulfate precipitation, 2',5'-ADP Sepharose 4B affinity chromatography, and gel filtration chromatography on Sephadex G-200. 5-(3alpha-Hydroxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (1), 5-(3alpha,12alpha-Dihydroxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (2), 5-(3alpha,7alpha,12alpha-Trihydroxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (3), 5-(3alpha,Acetoxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (4), 5-(3alpha,7alpha,12alpha-Triacetoxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (5), 5-(3,7,12-Trioxo-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (6), acetazolamide, and dorzolamide were tested in this experiment. Compounds 3, 5, and dorzolamide showed inhibitory effects on the activity of 6-phosphogluconate dehydrogenase, and I(50) values and K(i) constants were calculated as 0.0601 mM, 0.00253 mM, and 1.41 mM and 0.0878 +/- 0.0274 mM, 0.0042 +/- 0.0009 mM, and 3.1446 +/- 0.2081 mM, respectively. Glutathione reductase was also inhibited by 1 and 2. I(50) values and K(i) constants were 0.0471 mM and 0.0723 +/- 0.0388 mM for 1 and 0.0045 mM and 0.0061 +/- 0.0014 mM, for 2. If these sulfonamide derivatives are proposed as drugs, some of which are being used in glaucoma treatment such as acetazolamide and dorzolamide, these results should be taken into consideration concerning via these enzymes.

Fatty acid composition, conjugated linoleic acid and cholesterol contents in the muscles of three freshwater fish species (Barbus plebejus escherichi, Capoeta capoeta capoeta and Rutilus rutilus) were determined under natural extreme temperate (July) and cold (January) conditions. The aim of the study was to determine whether there were differences in these components of the muscle lipids among these three fish species under extreme natural conditions. Samples were analyzed using gas chromatography. Palmitic, oleic, docosahexaenoic and eicosapentaenoic acids were the predominant fatty acids in all fish in both months. The percentages of polyunsaturated fatty acids, n - 3 polyunsaturated fatty acids, n - 6 polyunsaturated fatty acids and eicosapentaenoic + docosahexaenoic acids in the muscle of B. plebejus escherichi and C. capoeta capoeta were significantly higher in January (P < 0.05) than in July. The ratio of n - 6 to n - 3 polyunsaturated fatty acids was lower than 0.60 in all fish species, with C. capoeta capoeta showing the lowest ratio in January (0.36). The levels of cholesterol and conjugated linoleic acid ranged from 103.46 to 150.10 mg/100 g oil and from 16.27 to 35.45 mg/100 g oil, respectively, for all samples in both months. There were no statistical differences in cholesterol levels among the three fish species in July and January. Conjugated linoleic acid contents were significantly higher in January in B. plebejus escherichi and C. capoeta capoeta. Of the three species tested, the extreme temperate and cold conditions affected B. plebejus escherichi the most. © Springer Science+Business Media B.V. 2008.

Effects of nicotine, nicotine + vitamin E and nicotine + Hippophea rhamnoides L. extract (HRe-1) on muscle, heart, lungs, testicle, kidney, stomach, brain and liver carbonic anhydrase (CA; EC 4.2.1.1.) enzyme activities were investigated in vivo. Groups of rats were given nicotine (0.5 mg/kg/day, i.p.), nicotine + vitamin E (75 mg/kg/day, i.g.), nicotine + HRe-1 (250 mg/kg/day, i.g.) and a control group vehicle only. The results showed that nicotine inhibited the heart, lung, stomach and liver CA enzyme activities by approximately 80% (p < 0.001), approximately 94% (p < 0.001), approximately 47% (p < 0.001) and approximately 81% (p < 0.001) respectively, and activated muscle and kidney, but had no effects on the testicle and brain CA activities. Nicotine + vitamin E inhibited the heart and liver CA enzyme activities by approximately 50% (p < 0.001), and approximately 50% (p < 0.001), respectively, and nicotine + vitamin E activated the muscle CA activity. However, nicotine + vitamin E had no effect on lung, testicle, kidney, stomach and brain CA activities. Nicotine + HRe-1 inhibited the heart and stomach CA enzyme activities by approximately 51% (p < 0.001), and approximately 32% (p < 0.002), respectively, and activated the muscle and brain CA activities, but had no effects on the lung, testicle, kidney, and liver CA activities. In vitro CA inhibition results for similar experiments correlated well with the in vivo experimental results in lungs, testicles, kidney, stomach, brain and liver tissues.

The in vitro and in vivo inhibitory effects of 5-(3alpha, 12alpha-dihydroxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (1), 5-(3alpha, 7alpha, 12alpha-trihydroxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (2), 5-(3alpha, 7alpha, 12alpha-triacetoxy-5-beta-cholanamido)-1,3,4-thiadiazole-2-sulfonamide (3) and acetazolamide on rainbow trout (Oncorhynchus mykiss) (RT) erythrocyte carbonic anhydrase (CA) were investigated. The RT erythrocyte CA was obtained by affinity chromatography with a yield of 20.9%, a specific activity of 422.5EU/mg protein and a purification of 222.4-fold. The purity of the enzyme was confirmed by SDS-PAGE. Inhibitory effects of the sulfonamides and acetazolamide on the RT erythrocyte CA were determined using the CO2-Hydratase method in vitro and in vivo studies. From in vitro studies, it was found that all the compounds inhibited CA. The obtained I50 value for the sulfonamides (1), (2) and (3) and acetazolamide were 0.83, 0.049, 0.82 and 0.052 microM, respectively. From in vivo studies, it was observed that CA was inhibited by the sulfonamides (1), (2) and (3) and acetazolamide.

Bile acid amides (cholan-24-amides) of 5-substituted 1,3,4-thiadiazole-2-sulfonamide have been prepared from lithocholic, deoxycholic, cholic and dehydrocholic acids. Besides, the alcohol functional groups on the cholane ring systems were protected with acetyl group. Amides of the protected cholanes of lithocholic and cholic acids were also synthesized. Later, inhibition effects of these compounds on human carbonic anhydrase isozymes (HCA-I and II) have been investigated in vitro. For the most active compounds, inhibition constants ranged from 66 to 190 nM for HCA-II with I 50 (molarity of inhibitor producing a 50% inhibition of CA activity). In addition, in vivo studies were performed for the synthesized compounds in Sprague–Dawley rats. The compounds ( 11 and 18 ) showed especially significant inhibition efficacy ( p