Synthesis, Characterization, Antimicrobial, DNA Cleavage, and Antioxidant Studies of Some Metal Complexes Derived from Schiff Base Containing Indole and Quinoline Moieties

Abstract

A new Schiff base of 5-chloro-3-phenyl-1H-indole-2-carboxyhydrazide and 3-formyl-2-hydroxy-1H-quinoline (HL), and its Cu(II), Co(II), Ni(II), Zn(II), Cd(II), and Hg(II) complexes have been synthesized and characterized in the light of microanalytical, IR, H1 NMR, UV-Vis, FAB-mass, ESR, XRD, and TGA spectral studies. The magnetic susceptibility measurements and low conductivity data provide evidence for monomeric and neutral nature of the complexes. On the basis of spectral studies and analytical data, it is evident that the Schiff base acts as tridentate ligand. The Cu(II), Co(II), and Ni(II) complexes were octahedral, whereas Zn(II), Cd(II), and Hg(II) complexes were tetrahedral in nature. The redox behavior of the Cu(II) complex was investigated by electrochemical method using cyclic voltammetry. In order to evaluate the effect of metal ions upon chelation, both the ligand and its metal complexes were screened for their antibacterial and antifungal activities by minimum inhibitory concentration (MIC) method. The DNA cleavage experiment performed using agarose gel electrophoresis method showed the cleavage of DNA by all the metal complexes. The free radical scavenging activity of newly synthesized compounds has been determined at a different concentration range by means of their interaction with the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH).

Synthesis, Spectral Characterization and Thermal Behaviour of New Metal(ii) Complexes With Schiff Base Derived From Amoxicillin

“…An antibacterial activity of metal complexes better than the one of the Schiff base ligand can be explained on the basis of Overtone's and Tweedy's concepts 32,33 . According to Overtone's concept of cell permeability, the lipid membrane that surrounds the cell favours only the passage of lipid soluble materials, therefore liposolubility is considered to be an important factor that controls the antibacterial activity.…”

Synthesis, Characterization and Evaluation of Anti-inflammatory and Analgesic Activity of Some Novel Quinoline Based Thiazolidinone Heterocycles

“…Synthesis of target compounds (13)(14)(15)(16)(17)(18)(19)(20)(21)(22) was achieved as outlined in Schemes 1 and 2. The starting material 2-hydrazinylquinoline 2 was synthesized in a high yield from the reaction of hydrazine hydrate with 2-chloroquinoline 1 in refluxing n-butanol, through procedures previously reported [35].…”

“…The reaction mixture was refluxed for 24 h (monitored by TLC). The mixture was cooled to room temperature and the formed precipitate was filtered off and recrystalized from ethanol to give the expected thiazolidinone derivatives (13)(14)(15)(16)(17)(18)(19)(20).…”

“…The formed precipitate was filtered off, dried and recrystallized from appropriate solvent to give target compounds. In case of no precipitate formed upon cooling, the solution was added to water and neutralized using Na 2 CO 3 solution, the formed precipitate was filtered, dried and recrystallized to obtain the expected thiazolidinone products (13)(14)(15)(16)(17)(18)(19)(20), respectively.…”

“…The chemistry of quinoline derivatives has been of increasing interest due to their vast chemical reactivity, biological and pharmaceutical activities [1][2][3][4][5]. It has been reported that these derivatives possesses anti-tuberculosis [6,7], Antiplasmodial [4], Antibacterial [5], antihistamine [6], anticancer [11][12][13][14], anti-hypertensive [9], antifungal [10], antimalarial [11], anti-HIV [12] and antioxidant activities [13]. On the other hand, thiazole and thiazolidinone derivatives are known to exhibit diverse biological activities [14][15][16], they have anti-inflammatory [20,21], anticancer, antimicrobial [19], anti-tuberculosis [20] and antioxidant activity [21].…”