title: Synthesis, structures, spectroscopy and antimicrobial properties of complexes of copper(II) with salicylaldehyde N-substituted thiosemicarbazones and 2,2'-bipyridine or 1,10-phenanthroline.
abstract: Among the biometals (Cu, Co, Ni-cofactors in many enzymes), copper derivatives of O, N, S-donor salicylaldehyde thiosemicarbazones have received considerable attention owing to their potential biological applications. Eight new complexes of salicylaldehyde-N-substituted thiosemicarbazones [5-MeO-2-HO-C₆H₄-C(2)(H)N(3)-N(2)H-C(1)(S)-N(1)HR; R = Me, H2L(1); Et, H₂L(1), Ph, H₂L(3), H, H₂L(4)] with copper(II), namely, [Cu(κ(3)-O,N,S-L)( κ(2)-N,N-L')] {(L)(2-) = (L(1))(2-), L' = bipy, 1, phen, 2; (L)(2-) = (L(2))(2-), L' = bipy, 3, phen, 4; (L)(2-) = (L(3))(2-), L' = bipy, 5, phen, 6; (L)(2-) = (L(4))(2-), L' = bipy, 7, phen, 8} have been isolated. Complexes have slightly distorted square pyramidal geometry around the metal center (τ parameter = 0.243-0.357) and display weak to intense fluorescence in the region, 375-475 nm. These copper complexes have shown significant growth inhibitory activity (antimicrobial activity) against Staphylococcus aureus (MTCC740), methicillin resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae 1 (MTCC109), Shigella flexneri (MTCC1457), Pseudomonas aeruginosa (MTCC741) and Candida albicans (MTCC227). The activity against MRSA is an interesting observation as the commercially available gentamycin is found to be inactive against this bacterial strain. Specifically complex 5 formed by 5-methoxysalicylaldehyde-N-phenylthiosemicatbazone has shown novel antimicrobial activity against various bacteria and yeast investigated.
authors.affiliation: Department of Chemistry, Guru Nanak Dev University, Amritsar 143 005, India. Electronic address: tslasr@gmail.com.
authors.forename: Tarlok S
authors.initials: TS
authors.lastname: Lobana
authors.affiliation: Department of Chemistry, Guru Nanak Dev University, Amritsar 143 005, India.
authors.forename: Shikha
authors.initials: S
authors.lastname: Indoria
authors.affiliation: Department of Chemistry, Guru Nanak Dev University, Amritsar 143 005, India.
authors.forename: Amanpreet Kaur
authors.initials: AK
authors.lastname: Jassal
authors.affiliation: Department of Microbiology, Guru Nanak Dev University, Amritsar 143 005, India.
authors.forename: Harpreet
authors.initials: H
authors.lastname: Kaur
authors.affiliation: Department of Microbiology, Guru Nanak Dev University, Amritsar 143 005, India.
authors.forename: Daljit S
authors.initials: DS
authors.lastname: Arora
authors.affiliation: Department of Chemistry, Keene State College, Keene, NH 03435, USA.
authors.forename: Jerry P
authors.initials: JP
authors.lastname: Jasinski
mesh_terms: D015082:2,2'-Dipyridyl / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D000447:Aldehydes / Q000737:chemistry*; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D010618:Phenanthrolines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013057:Spectrum Analysis / Q000379:methods; D013882:Thiosemicarbazones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000447:Aldehydes; D000900:Anti-Bacterial Agents; D010618:Phenanthrolines; D013882:Thiosemicarbazones; C013243:salicylaldehyde; D015082:2,2'-Dipyridyl; D003300:Copper; C025205:1,10-phenanthroline
keywords: 1,10-Phenanthroline; 2, 2′-Bipyridine; Biological activity; Copper(II); Fluorescence; Salicylaldehyde thiosemicarbazones