SYNTHESIS, STRUCTURAL, SPECTRAL AND EPR STUDIES ON THE COPPER(II) COMPLEX OF 5-(AMINOSULPHONYL)-4-CHLORO-2-[(2-FURANYLMETHYL)AMINO]BENZOIC ACID(FUROSEMIDE)

The copper(II) complexes of Furosemide (Fu) widely used as a diuretic were synthesized and isolated from aqueous and methanol solutions as CuFu2.2Solv and characterized by elemental analysis, single crystal X-ray diffraction, UV-vis and IR spectroscopy, EPR and magnetic susceptibility measurements. The complex CuFU2. 2MeOH was isolated from methanol solutions as green crystals. Its structure consists of flattened molecules arranged in stacks. A centrosymmetric CuO6 elongated bipyramid is formed around copper(II) by four oxygens from the COO- groups and two from the MeOH. The COO- groups act as bridges between the copper(II) atoms with two oxygens in the equatorial plane (Cu-O distance of 1.924 angstrom) and the other two in apical positions at 2.720 angstrom. The methanol oxygens are at an intermediate distance of 1.941 angstrom. The Cu-Cu separation is 4.749 angstrom. Hydrogen bonding occurs within and between the molecules.