| Home  | About ScienceAsia  | Publication charge  | Advertise with us  | Subscription for printed version  | Contact us  
Editorial Board
Journal Policy
Instructions for Authors
Online submission
Author Login
Reviewer Login
Volume 43 Number 3
Volume 43 Number 2
Volume 43 Number 1
Volume 43S Number 1
Volume 42 Number 6
Volume 42S Number 1
Earlier issues
Volume 43 Number 2 Volume 43 Number 3

previous article next article 1

Research articles

ScienceAsia 43(2017): 175-185 |doi: 10.2306/scienceasia1513-1874.2017.43.175

Synthesis, characterization, and biological studies of novel Ni(II) and Zn(II) complexes with 5-chloro-2-(phenylazo)pyridine

Luksamee Vittayaa,*, Nararak Leesakulb, Saowanit Saithongb, Souwalak Phongpaichitc, Phoom Chumponanomakund, Theerapoom Boonprabb, Kittipong Chainokd, Yuthana Tantirungrotechaid

ABSTRACT:     An azoimine compound, 5-chloro-2-(phenylazo)pyridine (Clazpy), reacted with Ni(II) and Zn(II) sulphate salts and formed divalent metal complexes with a general formula of [M(Clazpy)2(NCS)2], where M is Ni(II) or Zn(II). The synthesized complexes were characterized on the basis of elemental analysis, nuclear magnetic resonance, and infrared and electronic absorption spectroscopy. The single crystal X-ray diffraction and infrared data of the Zn(II) complex show that the ligand coordinates through the donating nitrogen atoms of the pyridine ring and azo moiety of Clazpy and N atoms of the thiocyanate groups. Our density functional theory calculations used the B3LYP/6-31G(d,p)&LANL2DZ functional and basis sets to predict the most favourable structures of [Ni(Clazpy)2(NCS)2] and [Zn(Clazpy)2(NCS)2]. The TD-CAM-B3LYP/6-31+G(d,p)&LANL2DZ electronic transition energies agree with the electronic spectra and hence confirm their structures. Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations or minimal fungicidal concentrations (MFC) of all tested compounds were determined against human pathogens by a colorimetric microdilution method. The Clazpy compound and its complexes are significantly active against yeast and filamentous fungus with MIC and MFC values of 32 and 200 µg/ml, respectively. The Clazpy ligand showed higher antimicrobial activities against pathogenic yeast Cryptococcus neoformans (MIC/MFC 32/32 µg/ml) than both complexes (MIC/MFC 64/128 µg/ml). The [Ni(Clazpy)2(NCS)2] complex exhibited higher antimicrobial activities against fungal strains of Microsporum gypseum (MIC/MFC 64/128 µg/ml) than the [Zn(Clazpy)2(NCS)2] complex. These new azoimine metal complexes might therefore be considered as prospective antifungal agents.

Download PDF

16 Download 72 View

a Faculty of Science and Fisheries Technology, Rajamangala University of Technology Srivijaya, Sikao, Trang 92150 Thailand
b Department of Chemistry and Centre for Innovation in Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110 Thailand
c Natural Products Research Centre and Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90110 Thailand
d Department of Physics, Faculty of Science and Technology, Thammasat University, Klong Luang, Pathumthani 12120 Thailand

* Corresponding author, E-mail: nokluksamee@hotmail.com

Received 18 Sep 2015, Accepted 2 Jul 2017