Synthesis and DNA binding studies of novel heterocyclic substituted quinoline Schiff bases: A potent antimicrobial agent

The present article deals with the synthesis of 2-chloroquinoline-3-carbaldehyde [(2-hydroxy-1-naphthyl) methylene] hydrazone (CQCMH) (2a-c) and 2-chloroquinoline-3-carbaldehyde [4-(dimethylamino) benzylidene] hydrazone (CQCDBH) (3a-c) from quinoline derivatives under suitable experimental conditions. The synthesized compounds were characterized by elemental analysis, FTIR, (HNMR)-H-1, and mass spectral data. The selected compounds were studied for interaction with calf thymus-DNA (CT-DNA) by electronic spectra, viscosity measurements as well as thermal denaturation studies. On binding to DNA, the absorption spectrum underwent bathochromic and hypochromic shifts. The binding constant (Kb) had value of 2.3 x 10(3) M-1 for (2a) and 2.5 x 10(4) M-1 for (3a). The viscosity measurements indicated that the viscosity of sonicated rod like DNA fragments increased. The synthesized derivatives have been screened for antibacterial and antifungal activities.