CRYSTAL STRUCTURE OF BIS(ISOQUINOLINE-1-CARBOXALDEHYDE THIOSEMICARBAZANATO)NICKEL(II) MONOHYDRATE

The crystal structure of bis(isoquinoline-1-carboxaldehyde thiosemicarbazanato)nickel(II) monohydrate was determined. The ligand is a potent tumor inhibitor that was believed to function because of its metal-chelating ability. The formation of the nickel complex involving the tridentate ligand is compatible with the chelation hypothesis. The compound crystallizes in the monoclinic space group C2/c with a = 17.884, b = 17.567, c = 15.901 Å, β = 101.57°, and eight molecules per cell. The final R for 2464 observed reflections is 0.060. The distorted octahedral molecules are held together by a hydrogen-bond system involving N–H· · ·N, N–H· · ·O, and O–H · · · S hydrogen bonds. The presence of the rare O–H · · · S hydrogen bond is an unusual feature of the structure. © 1969, American Chemical Society. All rights reserved.