## 1 Introduction  
Pyrinidine derivatives possess a wide range of biological activities, such as antineoplastic [1], antiviral [2], antimicrobial [3], free radical scavenging [4], anti-inflammatory [5], pain-relieving [6], and anxiety-reducing [7] properties. Thionamides, a class of relatively simple molecules, serve as antihydroid drugs, featuring a sulfhydryl group and a thiourea moiety within a heterocyclic framework. In the United States, the antihyroid drugs in use are Propylthiouracil (also known as 6-propyl-2-thioouracil) and Methimidazole (also referred to as 1-methyl-2-mercaptoethanolimidazole or Tapazole). [PERSON] and [PERSON] provided a comprehensive review of the coordination possibilities of uracil and the practical applications of some of its complexes [8]. [PERSON] et al. synthesized metal complexes involving pyrimidine, which encompass Cd- and Zn-bributurate, as well as Cd- and Hg-thioouracil compounds [9]. The reaction of 5-bromouracil led to the preparation of novel complexes involving Mn(II), Cd(II), Co(II), Ni(II), Cu(II), and Ag(I) [10]. The data obtained demonstrated that these complexes exhibited greater antimicrobial potency compared to the free ligand. The interest in platinum and palladium complexes stems from their pronounced cytostatic activity. Recently, _cis_-dihalogeno complexes of Pt(II) and Pd(II) were synthesized in conjunction with 6-_tert_-butyl-2-thiouracil [11]. Furthermore, a series of complexes were synthesized using Rh(III), Ir(III), Pt(II), and Pd(II) in combination with the ligand 6-methyl-2-thiouracil [12]. [PERSON] et al. conducted a synthesis of Ru(II) complexes involving 6-methyl-2-thiouracil, showing promise for novel antileukemic drug candidates [13]. [PERSON] et al. successfully synthesized new Cu(I) complexes featuring the antithyroid drug 6-propyl-thiouracil [14]. To date, a multitude of metal complexes have been synthesized using uracil and thiouracil derivatives, involving various metals such as Cu, Fe, Co, Ni, Zn, Mn, Cd, and V [15; 16; 17], as well as Pd, Pt, and Au, with evaluations of their composition and structure [18]. In vitro screening of the antimicrobial activity of numerous metal complexes derived from thiouracil derivatives was conducted against Gram-positive and Gram-negative bacteria, filamentous fungi, and yeast [9; 19; 20; 21]. Furthermore, the cytotoxic effects of various metal complexes of thiouracil derivatives were investigated against different tumor cell lines [13; 22; 23; 24; 25; 26]. In Scheme 1 (top), the chemical structures of 6-methyl-2-thiouracil and 6-propyl-2-thiouracil are shown. Various metal complexes exhibit a monodentate coordination mode with 2-thiouracil derivatives, binding through different atoms, such as N1 (e.g., Cu(I) complex) [27], N3 (e.g., Pd(II) complex) [28], S (e.g., Ru(II), Cu(I), Sn(IV), Pt(II), and Pd(II) complexes) [11; 14; 23; 29], or O (e.g., Co(II), Ni(II), Mn(II), and Zn(II) complexes) [30; 31; 32]. **Scheme 1. ** Structure of 6-methyl-2-thiouracil and 6-propyl-2-thiouracil, including the atoms numbering and representation of coordination binding sites. At the bottom of Scheme 1, the bidentate coordination modes of these ligands are highlighted. There are at least four potential bidentate coordination possibilities (A\(-\)D) for both ligands. Some of these modes were examined by [PERSON] and colleagues [12], who discussed coordination modes represented in (A) and (B) in the presence of platinum and rhodium centers, respectively. These were the most common coordination modes for this ligand class. Complexes with Pt(II), Pd(II), Ru(II), and Zn(II) also display coordination mode (A) [12; 13; 28; 33], while coordination mode (B) was observed in Cd(II), Hg(II), and Co(II) complexes and peroxo complexes of vanadium [9; 34]. To date, possibility (C) has not been observed for thiouracil derivatives, except in an osmium/uracil complex [35] and Mn(II), Co(II), Ni(II), Cu(II), Cd(II), and Ag(I) with 5-bromo-uracil [10] and similar ligand [36].