The thionamide antithyroid drugs were discovered largely following serendipitous observations by numerous researchers in the 1940s who found that sulfhydryl-containing compounds were goitrogenic in animals. Prof. Edwin B. Astwood was the first to use these compounds to treat hyperthyroidism. In this review, we summarize the history of the development of these drugs and the coordination possibility of 2-thiouracil and its derivatives, as well as the biological activities of some of its complexes. Some of them are used as agents for the treatment of tuberculosis, and arthritis, others have bactericidal and fungicidal activity, the third cytotoxic properties, and could be used to treat various types of cancer.

Peptides, both natural and synthetic, are well suited for a wide range of purposes and offer versa-tile applications in different fields such as biocatalysts, injectable hydrogels, tumor treatment, and drug delivery. The rising prominence of therapeutic peptides encompasses anticancer, antiviral, antimicrobial, and anti-neurodegenerative properties. The metals Na, K, Mg, Ca, Fe, Mn, Co, Cu, Zn, and Mo are ten of the twenty elements that are considered essential for life. Crucial for under-standing the biological role of metals is the exploration of metal-bound proteins and peptides. Aside from essential metals, there are other, non-essential metals that also interact biologically, exhibiting either therapeutic or toxic effects. Irregularities in metal binding contribute to diseases like Alzheimer’s, neurodegenerative disorders, Wilson's, and Menkes disease. Certain metal com-plexes have potential applications as radiopharmaceuticals. The examination of these complexes was done by preforming UV-Vis, IR, EPR, NMR spectroscopy, and X-ray analysis.

The primary objective of this study is to synthesize, elucidate the structural properties, and ex-plore the biological activity of novel metal complexes derived from 6-methyl-2-thiouracil and 6-propyl-2-thiouracil. The paper outlines a synthesis method and assesses the antimicrobial activ-ity of newly formed Cu(II) and Pd(II) complexes with two substituted 2-thiouracil ligands. The structural attributes of these newly developed compounds are thoroughly discussed based on data derived from melting point analysis, MP-AES for Cu and Pd, UV-Vis, IR, ATR, 1H NMR, 13C NMR and Raman spectroscopy. The interpretation of the complex spectra is assisted by the data for 6-methyl-2-thiouracil and 6-propyl-2-thiouracil obtained from 1H-1H COSY, DEPT-135, HMBC and HMQC spectra. In addition, the antimicrobial activity of these complexes and the free ligands are assessed against both Gram-positive and Gram-negative bacteria, as well as yeasts.