Selective Urease Inhibitory and Antimicrobial Activities of Transition Metal Complexes of Amino Acid Bearing Schiff Base
- PDF / 883,594 Bytes
- 9 Pages / 594 x 792 pts Page_size
- 96 Downloads / 228 Views
Pharmaceutical Chemistry Journal, Vol. 54, No. 5, August, 2020 (Russian Original Vol. 54, No. 5, May, 2020)
SELECTIVE UREASE INHIBITORY AND ANTIMICROBIAL ACTIVITIES OF TRANSITION METAL COMPLEXES OF AMINO ACID BEARING SCHIFF BASE LIGAND: THERMAL DEGRADATION BEHAVIOR OF COMPLEXES Muhammad Ikram,1,* Sadia Rehman,1 Muhammad Nadeem Akhtar,2 Fazle Subhan,1 and Sobia Aslam1 Original article submitted October 26, 2019. Amino acid derived Schiff base ligand [1-({[(Z)-(2-hydroxynaphthalen-1-yl)methylidene]-amino}methyl)cyclohexyl]acetic acid (H-HMAC) and its metal complexes with composition [M(HMAC)2] [M = Co(II), Ni(II), Cu(II), and Zn(II)] reported previously were studied for their thermal degradation, antimicrobial and inhibitory activities against the enzymes like urease, a-chymotrypsin, acetylcholinesterase and butyrylcholinesterase. Only a zinc-based compound of the zwitter-ion ligand has been found to inhibit the urease activity with IC50 = 0.04 ± 0.01 mM (value ± SEM), which is 400 times better than the standard reference drug used. Metal coordination with zinc improved the bioactivity and deserved for selective urease inhibitor development. The inhibitory activity was structurally rationalized by carrying out the molecular modeling studies using AutoDock software. The same metal complex was also observed to inhibit the activity of Candida albicans. The thermal degradation studies suggest that the order of stability and activation energies of all compounds is as follows: Cu < H-HMAC < Ni < Co = Zn and E*Zn > E*Co > E*Ni > E*Cu, respectively. Keywords: urease inhibition, molecular modeling, antimicrobial activity, thermal degradation, thermodynamic study; kinetic study.
hypothesized that derivatives of such active agent may enhance the activity. A novel Schiff base derivative was obtained after reacting gabapentin with 2-hydroxynaphthaldehyde. The new Schiff base ligand is bearing amino acid properties and carries hydroxyl and carboxyl groups. The –OH substituted Schiff bases were studied previously for their capabilities of scavenging free radicals, enzyme inhibition, antimicrobial activities etc. [9 – 15]. Schiff bases are much exploited ligands for good coordination ability through p electrons of –C=N– linkage. A geometrical constriction is produced upon complexation of such chiral Schiff bases, a property used in the enhanced oxidation catalytic activity of transition metal complexes [12]. Changes in electrochemical behavior and magnetic properties can allow such complexes to be used for various applications including catalysis, medicines and reagents in laboratories. Iminium derivatives of salicylaldehyde were treated as monoanionic ligands and employed as bidentate ligands coordinating through N/O sites of attachment. Transition metal complexes with such bidentate ligands were studied for their enhanced reactivity toward dioxygen species [12 – 16].
1. INTRODUCTION Gabapentin is an amino acid used for its therapeutic applications in various drugs including antiepileptic, neuropathic, postherpetic, anticonvulsa
Data Loading...
