6533b82afe1ef96bd128b897

RESEARCH PRODUCT

A Co(III) complex of carbonic anhydrase inhibitor methazolamide and the amino-imino ‘aib’ ligand formed by reaction of acetone and ammonia

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description

Abstract Reaction of Co(NO 3 ) 2 ·6H 2 O with methazolamide {[ N -(3-methyl-5-sulfamoyl-1,3,4-thiadiazol-2(3 H )-ylidene)acetamide] (Hmacm)} and ammonia in acetone to produce [Co(methazolamidate)(2-methyl-2-amino-4-iminopentane) 2 (NH 3 )](NO 3 ) 2 ·2H 2 O is described. The ligand 2-methyl-2-amino-4-iminopentane (aib) is the product obtained from the condensation of two ammonia and two acetone molecules. The complex crystallizes in the monoclinic space group P 2 1 / c with a =16.713(5), b =9.180(1), c =20.273(1) A, β=97.44(4)° for Z =4. The R value is 0.081 for 2150 significant reflections. The Co(III) ion exhibits a nearly regular octahedral arrangement with the CoN bond distances in the range 1.91-1.98 A. The Co(III) ion is obtained by spontaneous oxidation of Co(II). Methazolamide interacts as a monodentate ligand through the deprotonated sulfonamido N atom in a similar way to the bonding of the inhibitor in the carbonic anhydrase enzyme.