Synthesis, X-ray structure and in vitro cytotoxicity studies of Cu(I/II) complexes of thiosemicarbazone: special emphasis on their interactions with DNA.
4-(p-X-phenyl)thiosemicarbazone of napthaldehyde {where X = Cl (HL¹) and X = Br (HL²)}, thiosemicarbazone of quinoline-2-carbaldehyde (HL³) and 4-(p-fluorophenyl)thiosemicarbazone of salicylaldehyde (H₂L⁴) and their copper(I) {[Cu(HL¹)(PPh₃)₂Br]·CH₃CN (1) and [Cu(HL²)(PPh₃)₂Cl]·DMSO (2)} and copper(II) {[(Cu₂L³₂Cl)₂(μ-Cl)₂]·2H₂O (3) and [Cu(L⁴)(Py)] (4)} complexes are reported herein. The synthesized ligands and their copper complexes were successfully characterized by elemental analysis, cyclic voltammetry, NMR, ESI-MS, IR and UV-Vis spectroscopy. Molecular structures of all the Cu(I) and Cu(II) complexes have been determined by X-ray crystallography. All the complexes (1-4) were tested for their ability to exhibit DNA-binding and -cleavage activity. The complexes effectively interact with CT-DNA possibly by groove binding mode, with binding constants ranging from 10⁴ to 10⁵ M⁻¹. Among the complexes, 3 shows the highest chemical (60%) as well as photo-induced (80%) DNA cleavage activity against pUC19 DNA. Finally, the in vitro antiproliferative activity of all the complexes was assayed against the HeLa cell line. Some of the complexes have proved to be as active as the clinical referred drugs, and the greater potency of 3 may be correlated with its aqueous solubility and the presence of the quinonoidal group in the thiosemicarbazone ligand coordinated to the metal.
Saswati
Ayon
A
Chakraborty
Subhashree P
SP
Dash
Alok K
AK
Panda
Rama
R
Acharyya
Ashis
A
Biswas
Subhadip
S
Mukhopadhyay
Sujit K
SK
Bhutia
Aurélien
A
Crochet
Yogesh P
YP
Patil
M
M
Nethaji
Rupam
R
Dinda
D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry; D002470:Cell Survival / Q000187:drug effects; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004247:DNA / Q000187:drug effects / Q000235:genetics; D053837:DNA Cleavage; D004278:DNA, Superhelical / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D012995:Solubility; D013882:Thiosemicarbazones / Q000737:chemistry*
D000970:Antineoplastic Agents; D056831:Coordination Complexes; D004278:DNA, Superhelical; D013882:Thiosemicarbazones; D003300:Copper; D004247:DNA; C427203:calf thymus DNA