Dinuclear zinc(ii) complexes of symmetric Schiff-base ligands with extended quinoline sidearms

Abstract

The synthesis of two 2-formylquinolines is reported via the Skraup method followed by SeO(2) oxidation. Each aldehyde is condensed with (1R,2R)-diaminocyclohexane and (R)-BINAM, yielding four enantiomerically-pure bis(imine-quinoline) ligands. The neutral ligands are reacted with ZnCl(2) to give complexes with bis(bidentate) coordination of ZnCl(2) units. X-Ray structural characterization of three complexes shows them to have a single-stranded helical motif, with M helicity, except in one case where a 1:1 mixture of M and P helices is seen. The ligands and complexes are further characterized spectroscopically by solution (1)H and (13)C NMR, UV-vis and ECD.

Synthesis, Characterization and Luminescence of Gold Complexes Bearing an NHC Ligand Based on the Imidazo[1,5‐a]quinolinol Scaffold

“…The compound crystallizes in the monoclinic space group P 2 1 / c with one molecule in the asymmetric unit (Figure 1, top). All geometric parameters are in the range expected 26. The aldehyde group is coplanar with the aromatic ring plane and the oxygen atom is in a trans position relative to the nitrogen atom of the quinoline moiety.…”

“…All geometric parameters are in the range expected. [26] The aldehyde group is coplanar with the aromatic ring plane and the oxygen atom is in a trans position relative to the nitrogen atom of the quinoline moiety. Yellow needles of 2 were obtained upon recrystallization in ethanol.…”

Manganese(III)-salens induce tumor selective apoptosis in human cells

“…Iron and copper based metallo-salen complexes have been shown to produce reactive oxygen species under reducing environment that damage DNA in a sequence neutral fashion in vitro and have been applied for studying drug-DNA interaction and foot-printing [40,41]. Furthermore, various iron-salen derivatives have been implicated in efficient asymmetric catalysis and in catalyzing hydrolytic cleavage of DNA and RNA [42][43][44][45]. Mn(III)-salen complexes are shown to posses superoxide dismutase (SOD) and catalase activities and are considered as synthetic SOD mimics [46,47].…”

Quinoline-2-carbaldehyde

“…For the synthesis of the title compound, see: Cooper & Cohen (1932). For its use in the synthesis of Schiff base ligands and imino-quinolyl-based transition metal complexes, see: Amandola & Mangano (2003); Prema & Wiznycia (2007); Ramos Silva et al (2007); Ardizzoia et al (2009). For its catalytic properties, see: Zhou et al (2008).…”