Complexes of N- and O-Donor Ligands as Potential Urease Inhibitors

Syed Raza Shah; Zarbad Shah; Mohammed Khiat; Ajmal Khan; Leila R Hill; Shakeel Khan; Javid Hussain; René Csuk; Muhammad U Anwar; Ahmed Al-Harrasi

doi:10.1021/acsomega.0c01089

Complexes of N- and O-Donor Ligands as Potential Urease Inhibitors

ACS Omega. 2020 Apr 20;5(17):10200-10206. doi: 10.1021/acsomega.0c01089. eCollection 2020 May 5.

Authors

Affiliations

¹ Natural and Medical Sciences Research Centre, University of Nizwa, Birkat Almouz, Nizwa 616, Oman.
² Department of Chemistry, Bacha Khan University Charsadda, Charsadda 24420 Khyber Pakhtunkhwa, Pakistan.
³ Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K.
⁴ Department of Biological Sciences and Chemistry, University of Nizwa, Birkat Almouz, Nizwa 616, Oman.
⁵ Organic Chemistry, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 2, Halle (Saale) d-06120, Germany.

Abstract

We report five new transition-metal complexes that inhibit the urease enzyme. Barbituric acid (BTA), thiobarbituric acid (TBA), isoniazid (INZ), and nicotinamide (NCA) ligands were employed in complexation reactions. The resulting complexes were characterized using a variety of analytical techniques including infra-red and UV-vis spectroscopy, ¹H NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction analysis. We describe two mononuclear complexes with a general formula {[M(NCA)₂(H₂O)₄](BTA)₂(H₂O)}, where M = Co (1) and Zn (2), a mononuclear complex {[Ni(NCA)₂(H₂O)₄](TBA)₂(H₂O)} (3), and two polymeric chains of a general formula {[M(INZ) (H₂O)₃](BTA)₂(H₂O)₃}, where M = Co (4) and Zn (5). These complexes displayed significant urease enzyme inhibition with IC₅₀ values in the range of 3.9-19.9 μM.