title: Synthesis, characterization and antiglaucoma activity of a novel proton transfer compound and a mixed-ligand Zn(II) complex.
abstract: A novel proton transfer compound, pyridin-2-ylmethanaminium 2,4-dichloro-5-sulfamoylbenzoate (1), and a mixed-ligand Zn(II) complex, bis(2,4-dichloro-5-sulfamoylbenzoate)(2-aminomethylpyridine)aquazinc(II) monohydrate (2), have been synthesized from the same free ligands, which are 2,4-dichloro-5-sulfamoylbenzoic acid (Hsba) and 2-aminomethylpyridine (amp). They have been characterized by elemental, spectral ((1)H NMR, IR and UV-vis.) and thermal analyses. Additionally, magnetic measurement and single crystal X-ray diffraction technique were applied to compound 2. In the complex, Zn(II) ion exhibits a distorted octahedral configuration coordinated by O1 and O1(i) atoms of two mono dentante sba anions and N1, N2, N2(i) atoms of bidentante amp anion and a water molecule (O1w). The free ligands Hsba and amp, and the products 1 and 2, and acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibitor effects on human Carbonic Anhydrase isoenzymes (hCA I and hCA II) purified from erythrocyte cell by affinity chromatography for their hydratase and esterase activities. The IC(50) values of products 1 and 2 for hydratase activity are 0.26 and 0.13microM for hCA I and 0.30 and 0.15microM for hCA II, respectively. The IC(50) values of the same inhibitors for esterase activity are 0.32 and 0.045microM for hCA I and 0.29 and 0.23microM for hCA II, respectively. In relation to esterase activities, the inhibition equilibrium constants (K(i)) were also determined and found 0.25 and 0.058microM on hCA I and 0.22 and 0.24microM on hCA II for 1 and 2, respectively. The comparison of the inhibition studies of newly synthesized compounds 1 and 2 to parent compounds Hsba and amp and to AAZ indicated that 1 and 2 have effective inhibitory activity on hCA I and II, and might be used potential inhibitors.
authors.affiliation: Department of Chemistry, Faculty of Arts and Sciences, Dumlupinar University, 43100 Kütahya, Turkey. yenikaya@dumlupinar.edu.tr
authors.forename: Cengiz
authors.initials: C
authors.lastname: Yenikaya
authors.forename: Musa
authors.initials: M
authors.lastname: Sari
authors.forename: Metin
authors.initials: M
authors.lastname: Bülbül
authors.forename: Halil
authors.initials: H
authors.lastname: Ilkimen
authors.forename: Hülya
authors.initials: H
authors.lastname: Celik
authors.forename: Orhan
authors.initials: O
authors.lastname: Büyükgüngör
mesh_terms: D024401:Carbonic Anhydrase I / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism; D024402:Carbonic Anhydrase II / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism; D002257:Carbonic Anhydrase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004912:Erythrocytes / Q000201:enzymology; D005901:Glaucoma / Q000188:drug therapy* / Q000201:enzymology / Q000378:metabolism; D006801:Humans; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011522:Protons; D017550:Spectroscopy, Fourier Transform Infrared; D013329:Structure-Activity Relationship; D013696:Temperature; D015032:Zinc / Q000737:chemistry*
chemical_list: D002257:Carbonic Anhydrase Inhibitors; D008024:Ligands; D009942:Organometallic Compounds; D011522:Protons; D024401:Carbonic Anhydrase I; D024402:Carbonic Anhydrase II; D015032:Zinc