Binuclear palladacycles with ionisable and non-ionisable tethers as anticancer agents

The search for novel anticancer agents to replace the current platinum-based treatments remains an ongoing process. Palladacycles have shown excellent promise as demonstrated by our previous work which yielded BTC2, a binuclear palladadycle with a non-ionisable polyethylene glycol (PEG) tether. Here, we explore the importance of the PEG-tether length on the anticancer activity of the binuclear palladacycles by comparing three analogous binuclear palladacycles, BTC2, BTC5 and BTC6, in the oestrogen receptor positive MCF7 and triple-negative MDA-MB-231 breast cancer cell lines. In addition, these are compared to another analogue with an ionisable morpholine tether, BTC7. Potent anticancer activity was revealed through cell viability studies (MTT assays) revealed that while BTC6 showed similar potent anticancer activity as BTC2, it was less toxic towards non-cancerous cell lines. Interestingly, BTC7 and BTCF were less potent than the PEGylated palladacycles but showed significantly improved selectivity towards the triple-negative breast cancer cells. Cell death analysis showed that BTC7 and BTCF significantly induced apoptosis in both the cancer cell lines while the PEGylated complexes induced both apoptosis and secondary necrosis. Furthermore, experimental and computational DNA binding studies indicated partial intercalation and groove binding as the modes of action for the PEGylated palladacycles. Similarly, experimental and computational BSA binding studies indicated and specific binding sites in BSA dependent on the nature of the tethers on the complexes.

Fabrication of thiosemicarbazone-based Pd(II) complexes: structural elucidations, catalytic activity towards Suzuki-Miyaura coupling reaction and antitumor activity against TNBC cells

Currently, there are many uses of metal complexes, especially in the fields of medicinal chemistry and catalysis. Thus, fabrication of new complexes which perform as a catalyst and chemotherapeutic drug is always a beneficial addition to the literature. Herein, we report three heterocyclic thiosemicarbazone-based Pd(II) complexes [Pd(HL1)Cl] (C1), [Pd(L2)(PPh3)] (C2) and [Pd(L3)(PPh3)]Cl (C3) having coligands Cl and PPh3. Thiosemicarbazone ligands (H2L1, H2L2 and HL3) and the complexes (C1-C3) were characterized methodically using several spectroscopic techniques. Single-crystal X-ray diffraction methods reveal that the structural environment around the metal center of C2 is square planar, while for C1 and C3 it is a slighty distorted square plane. The supramolecular network of compounds was built via hydrogen bonds, C-H⋯π and π⋯π interactions. Density functional theory (DFT) study of the structure of the complexes supports experimental findings. The application of these complexes as catalysts toward Suzuki-Miyaura coupling reactions has been examined with various aryl halides and phenyl boronic acid in PEG 400 solvent. The complexes displayed good biomolecular interactions with DNA/protein, with a binding constant value of the order of 105 M-1. C3 showed greater binding efficacy toward these biomolecules than the other complexes, which might be due to the cationic nature of C3. Furthermore, antitumor activity of the complexes was studied against the human triple-negative breast cancer (TNBC) cell line MDA-MB-231. It was found that C3 was more toxic (IC50 = 10 ± 2.90 μM) toward MDA-MB-231 cells than the other complexes. A known chemotherapeutic drug, 5-fluorouracil, was included as positive control. The programmed cell death mechanism of C3 was confirmed. Additionally, complex-induced apoptosis was confirmed and occurred via a mitochondria-dependent (intrinsic) pathway.

Indole-Containing Metal Complexes and Their Medicinal Applications

Indole is an important element of many natural and synthetic molecules with significant biological activity. Nonetheless, the co-presence of transitional metals in organic scaffold may represent an important factor in the development of effective medicinal agents. This review covers some of the latest and most relevant achievements in the biological and pharmacological activity of important indole-containing metal complexes in the area of drug discovery.

Biomedical applications of selective metal complexes of indole, benzimidazole, benzothiazole and benzoxazole: A review (From 2015 to 2022)

Indole, benzoxazole benzothiazole and benzimidazole are excellent classes of organic heterocyclic compounds. These compounds show significant application in pharmacy, industries, dyes, medicine, polymers and food packages. These compounds also form metal complexes with copper, zinc, cadmium, nickel, cobalt, platinum, gold, palladium chromium, silver, iron, and other metals that have shown to be significant applications. Recently, researchers have attracted enormous attention toward heterocyclic compounds such as indole, benzimidazole, benzothiazole, benzoxazole, and their complexes due to their excellent medicinal applications such as anti-ulcerogenic, anti-cancer, antihypertensive, antifungal, anti-inflammatory, antitubercular, antiparasitic, anti-obesity, antimalarial, antiglycation, antiviral potency, antineuropathic, analgesic antioxidant, antihistaminic, and antibacterial potentials. In this article, we summarize the medicinal applications of these compounds as well as their metal complexes. We hope this article will help researchers in designing and synthesizing novel and potent compounds with significant applications in various fields.

Crystal Design, Antitumor Activity and Molecular Docking of Novel Palladium(II) and Gold(III) Complexes with a Thiosemicarbazone Ligand

The current research describes the synthesis and characterization of 2-acetylpyridine N(4)-cyclohexyl-thiosemicarbazone ligand (HL) and their two metal complexes, [Au(L)Cl][AuCl₂] (1) and [Pd(L)Cl]·DMF (2). The molecular structures of the compounds were determined by physicochemical and spectroscopic methods. Single crystal X-ray diffraction was employed in the structural elucidation of the new complexes. The complexes showed a square planar geometry to the metal center Au(III) and Pd(II), coordinated with a thiosemicarbazone molecule by the NNS-donor system and a chloride ion. Complex (1) also shows the [AuCl₂]^- counter-ion in the asymmetric unit, and complex (2) has one DMF solvent molecule. These molecules play a key role in the formation of supramolecular structures due to different interactions. Noncovalent interactions were investigated through the 3D Hirshfeld surface by the d_norm function and the 2D fingerprint plots. The biological activity of the compounds was evaluated in vitro against the human glioma U251 cells. The cytotoxicity results revealed great antitumor activity in complex (1) compared with complex (2) and the free ligand. Molecular docking simulations were used to predict interactions and properties with selected proteins and DNA of the synthesized compounds.

Transition Metal Complexes of Thiosemicarbazides, Thiocarbohydrazides, and Their Corresponding Carbazones with Cu(I), Cu(II), Co(II), Ni(II), Pd(II), and Ag(I)-A Review

This review focuses on some interesting and recent applications of transition metals towards the complexation of thiosemicarbazides, thiocarbohydrazides, and their corresponding carbazones. We started the review with a description of the chosen five metals, including Cu[Cu(I), Cu(II], Co(II), Ni(II), Pd(II), and Ag(I) and their electronic configurations. The stability of the assigned complexes was also discussed. We shed light on different routes describing the synthesis of these ligands. We also reported on different examples of the synthesis of Cu(I), Cu(II), Co(II), Ni(II), Ag(I), and Pd(II) of thiosemicarbazide and thiocarbohydrazide complexes (until 2022). This review also deals with a summary of the fruitful use of metal complexes of thiosemicarbazones and thiocarbazones ligands in the field of catalysis. Finally, this recent review focuses on the applications of these complexes related to their biological importance.

Design and synthesis of heterocyclic azole based bioactive compounds: Molecular structures, quantum simulation, and mechanistic studies through docking as multi-target inhibitors of SARS-CoV-2 and cytotoxicity

Two heterocyclic azole compounds, 3-(2,3-dihydrobenzo[d]thiazol-2-yl)-4H-chromen-4-one (SVS1) and 5-(1H-indol-3-yl)-4-methyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (SVS2) were obtained unexpectedly from 2-aminothiophenol and 4-oxo-4H-chromene-3-carbaldehyde (for SVS1), and (E)-2-((1H-indol-3-yl)methylene)-N-methylhydrazine-1-carbothioamide in the presence of anhydrous FeCl₃ (for SVS2), respectively. The compounds were well characterized by analytical and spectroscopic tools. The molecular structures of both the compounds were determined by single crystal X-ray diffraction (XRD) study. The results obtained from density functional theory (DFT) study revealed the molecular geometry and electron distribution of the compounds, which were correlated well with the three-dimensional structures obtained from the single crystal XRD. DMol³ was used to calculate quantum chemical parameters [chemical potential (µ), global hardness (η), global softness (σ), absolute electronegativity (χ) and electrophilicity index (ω)] of SVS1 and SVS2. Molecular docking study was performed to elucidate the binding ability of SVS1 and SVS2 with SARS-CoV-2 main protease and human angiotensin-converting enzyme-2 (ACE-2) molecular targets. Interestingly, the binding efficiency of the compounds with the molecular targets was comparable with that of remdesivir (SARS-CoV-2), chloroquine and hydroxychloroquine. SVS1 showed better docking energy than SVS2. The molecular docking study was complemented by molecular dynamics simulation study of SARS-CoV-2 main protease-SVS1 complex, which further exemplified the binding ability of SVS1 with the target. In addition, SVS1, SVS2 and cisplatin were assessed for their cytotoxicity against a panel of three human cancer cells such as HepG-2 (hepatic carcinoma), T24 (bladder) and EA.hy926 (endothelial), as well as Vero (kidney epithelial cells extracted from an African green monkey) normal cells using MTT assay. The results showed that SVS2 has significant cytotoxicity against HepG-2 and EA.hy926 cells with the IC₅₀ values of 33.8 μM (IC₅₀ = 49.9 μM-cisplatin and 8.6 μM-doxorubicin) and 29.2 (IC₅₀ = 26.6 μM-cisplatin and 3.8 μM-doxorubicin), respectively.

In vitro cytotoxicity and antibacterial activity of [Pd(AMTTO)(PPh3)2]: a novel promising palladium(ii) complex

The synthesis and characterization of a novel palladium complex based on a bioactive 3-mercapto-1,2,4-triazine derivative have been investigated. The Pd(ii) complex showed excellent anticancer and antibacterial activity.

Synthesis, cytotoxicity and docking studies (with SARS-CoV-2) of water-soluble binuclear Ru-p-cymene complex holding indole thiosemicarbazone ligand

A water-soluble binuclear organometallic Ru-p-cymene complex [Ru(η⁶-p-cymene)(η²-L)]₂ (1) was prepared from (E)-2-((1H-indol-3-yl)methylene)-N-phenylhydrazine-1-carbothioamide (HL) and [RuCl₂(p-cymene)]₂ in methanol at room temperature under inert atmosphere. The structure of binuclear complex was analyzed by UV-Visible, FT-IR, NMR and mass spectroscopic methods. The solid-state structure of the complex was ascertained by single crystal X-ray diffraction technique. The complex exhibited pseudo-octahedral (piano-stool) geometry around Ru(II) ion. The cytotoxic property of the ligand and complex along with cisplatin was investigated against A549-lung, MCF-7-breast, HeLa-cervical, HepG-2-liver, T24-urinary bladder and EA.hy926-endothelial cancer cells, and Vero-kidney epithelial normal cells. The complex exhibited superior activity than cisplatin against A549, HeLa and T24 cancer cells with the IC₅₀ values of 7.70, 11.2, and 5.05 µM, respectively. The complexes were cytotoxic specifically to the cancer cells. Molecular docking studies showed good binding potential of the ligand and complex with the spike protein and main protease of SARS-CoV-2, indicating the promising role of these compounds as antiviral compounds.

Thiosemicarbazone(s)-anchored water soluble mono- and bimetallic Cu(ii) complexes: enzyme-like activities, biomolecular interactions, anticancer property and real-time live cytotoxicity

The reactions of CuCl2·2H2O with chromone thiosemicarbazone ligands containing a -H or -CH3 substituent on terminal N yielded monometallic Cu(ii) complexes [Cu(HL1)Cl2] (1) and [Cu(HL2)Cl2] (2), whereas bimetallic Cu(ii) complexes [Cu(μ-Cl)(HL3)]2Cl2 (3), [Cu(μ-Cl)(HL4)]2Cl2 (4) and [Cu(μ-Cl)(L5)]2 (5) were obtained when a -C2H5, -C6H11 or -C6H5 substituent was present, respectively, in the ligands. The complexes were characterized using elemental analyses, UV-Vis, FT-IR, EPR, mass and TGA studies. The structures of neutral monometallic and dicationic bimetallic complexes were confirmed by single crystal X-ray diffraction, and they exhibited a distorted square pyramidal geometry around Cu(ii) ions. The catecholase-mimicking activity of complexes 1-5 was examined spectrophotometrically, and the results revealed that all the complexes except 5 had the ability to oxidize 3,5-di-tert-butylcatechol (3,5-DTBC) to 3,5-di-tert-butylquinone (3,5-DTBQ) under aerobic conditions with moderate turnover numbers. In order to find the possible complex-substrate intermediates, a mass spectrometry study was carried out for complexes 1-4 in the presence of 3,5-DTBC. The phosphatase-like activity of 1-5 was also investigated using 4-nitrophenylphosphate (4-NPP) as a model substrate. All the complexes exhibited excellent phosphatase activity in DMF-H2O medium. The complexes displayed significant biomolecular interactions and antioxidant potential. Complex 3 showed good interaction with apoptotic CASP3 protein, VEGFR2 and PIM-1 kinase receptors as revealed by a molecular docking study. Complexes (3-5) exhibited promising cytotoxicity against HeLa-cervical cancer cells with IC50 values of 2.24 (3), 2.25 (4) and 3.77 (5) μM, respectively, and showed a two-fold higher activity than cisplatin. The active complex 3 showed complete inhibition of colony formation at 10 μM concentration. In addition, the acridine orange (AO)/ethidium bromide (EB) staining and real-time live cell imaging results confirmed that complex 3 induced cell death in HeLa cells.

N-substitution in isatin thiosemicarbazones decides nuclearity of Cu(II) complexes - Spectroscopic, molecular docking and cytotoxic studies

The mono- (1) and bi-nuclear (2) copper(II) complexes containing N-substituted isatin thiosemicarbazone(s) were synthesized, and characterized by analytical and spectroscopic (UV-Visible, FT-IR and EPR) techniques. Bimetallic nature of complex 2 was confirmed by single crystal X-ray crystallography. The structures predicted by spectroscopic and crystallographic methods were validated by computational studies. From the spectroscopic, crystallographic and computational data, the structures were found to be distorted square planar for 1 and distorted square pyramidal for 2. Molecular docking studies showed hydrogen bonding and hydrophobic interactions of the complexes with tyrosinase kinase receptors. Complex 1 exhibited promising cytotoxic activity against Jurkat (leukemia) cell line, and complex 2 displayed more activity against HeLa S3 (cervical) and Jurkat cell lines with the IC₅₀ values of 3.53 and 3.70 μM, respectively. Cytotoxicity of 1 (Jurkat) and 2 (Jurkat and HeLa S3) was better than that of cisplatin. Morphological changes in A549 (lung), HeLa S3 and Jurkat cell lines were examined in presence of the active complexes with the co-staining of Hoechst, AO (acridine orange) and EB (ethidium bromide) by fluorescence microscope.

Synthesis, Study, and Application of Pd(II) Hydrazone Complexes as the Emissive Components of Single-Layer Light-Emitting Electrochemical Cells

For the first time, square planar Pd(II) complexes of hydrazone ligands have been investigated as the emissive components of light-emitting electrochemical cells (LECs). The neutral transition metal complex, [Pd(L¹)₂]·2CH₃OH (1), (HL¹ = (E)-N'-(phenyl(pyridin-2-yl)methylene)isonicotinhydrazide), was prepared and structurally characterized. Complex 1 displays quasireversible redox properties and is emissive at room temperature in solution with a λ_max of 590 nm. As a result, it was subsequently employed as the emissive material of a single-layer LEC with configuration FTO/1/Ga/In, where studies reveal that it has a yellow color with CIE(x, y) = (0.33, 0.55), a luminance of 134 cd cm^-2, and a turn-on voltage of 3.5 V. Protonation of the pendant pyridine nitrogen atoms of L¹ afforded a second ionic complex [Pd(L¹H)₂](ClO₄)₂ (2) which is also emissive at room temperature with a λ_max of 611 nm, resulting in an orange LEC with CIE(x, y) = (0.43, 0.53). The presence of mobile anions and cations in the second inorganic transition metal complex resulted in more efficient charge injection and transport which significantly improved the luminance and turn-on voltage of the device to 188.6 cd cm^-2 and 3 V, respectively. This study establishes Pd(II) hydrazone complexes as a new class of materials whose emissive properties can be chemically tuned and provides proof-of-concept for their use in LECs, opening up exciting new avenues for potential applications in the field of solid state lighting.

Synthesis of Palladium(II) Complexes via Michael Addition: Antiproliferative Effects through ROS-Mediated Mitochondrial Apoptosis and Docking with SARS-CoV-2

Metal complexes have numerous applications in the current era, particularly in the field of pharmaceutical chemistry and catalysis. A novel synthetic approach for the same is always a beneficial addition to the literature. Henceforth, for the first time, we report the formation of three new Pd(II) complexes through the Michael addition pathway. Three chromone-based thiosemicarbazone ligands (SVSL1-SVSL3) and Pd(II) complexes (1-3) were synthesized and characterized by analytical and spectroscopic tools. The Michael addition pathway for the formation of complexes was confirmed by spectroscopic studies. Distorted square planar structure of complex 2 was confirmed by single-crystal X-ray diffraction. Complexes 1-3 were subjected to DNA- and BSA-binding studies. The complex with cyclohexyl substituent on the terminal N of thiosemicarbazone (3) showed the highest binding efficacy toward these biomolecules, which was further understood through molecular docking studies. The anticancer potential of these complexes was studied preliminarily by using MTT assay in cancer and normal cell lines along with the benchmark drugs (cisplatin, carboplatin, and gemcitabine). It was found that complex 3 was highly toxic toward MDA-MB-231 and AsPC-1 cancer cells with IC50 values of 0.5 and 0.9 μM, respectively, and was more efficient than the standard drugs. The programmed cell death mechanism of the complexes in MDA-MB-231 cancer cells was confirmed. Furthermore, the complexes induced apoptosis via ROS-mediated mitochondrial signaling pathway. Conveniently, all the complexes showed less toxicity (≥50 μM) against MCF-10a normal cell line. Molecular docking studies were performed with VEGFR2, EGFR, and SARS-CoV-2 main protease to illustrate the binding efficiency of the complexes with these receptors. To our surprise, binding potential of the complexes with SARS-CoV-2 main protease was higher than that with chloroquine and hydroxychloroquine.

Crystal structures and biological properties of aroylhydrazone Ni(II) complexes

Three aroylhydrazone ligands ((Z)-N'-([2,2'-bithiophen]-5-ylmethylene)-2-hydroxybenzohydrazide, HL1; (Z)-N'-([2,2'-bithiophen]-5-ylmethylene)-3-hydroxybenzohydrazide, HL2; and (Z)-N'-([2,2'-bithiophen]-5-ylmethylene)-4-hydroxybenzohydrazide, HL3) and their complexes with nickel (Ni(L1)₂, 1; Ni(L2)₂, 2; Ni(L3)₂∙DMF, 3) were synthesized and characterized by ESI-MS, NMR, IR, UV-vis and elemental analysis techniques. The molecular structure of ligand (HL2) and complexes 1-3 was confirmed by single crystal X-ray crystallography. The single crystal X-ray structure of complexes 1-3 showed a distorted square planar geometry around the metal center, and the ligands adopt a bidentate chelating mode. The interaction of calf thymus (ctDNA) with nickel(II) complexes was explored using absorption, emission spectrum, viscosity, and circular dichroism methods. These complexes exhibited moderate affinity for ctDNA through groove binding modes. The most efficient DNA binder was complex 2. The interaction of the complexes with DNA has also been supported by molecular docking study and molecular dynamics simulation. An in vitro cytotoxicity study of the complexes found low activity against human cervical (Hela) and breast (MCF-7) cancer cell lines, with the best results for complex 2, where IC50 values are 86 μM and 92 μM respectively.

Guedes da Silva MF, Marzano C. Synthesis, Characterization and Biological Activity of Novel Cu(II) Complexes of 6-Methyl-2-Oxo-1,2-Dihydroquinoline-3-Carbaldehyde-4n-Substituted Thiosemicarbazones

Three new 6-methyl-2-oxo-1,2-dihydroquinoline-3-carbaldehyde-thiosemicarbazones-N-4-substituted pro-ligands and their Cu(II) complexes (1, -NH2; 2, -NHMe; 3, -NHEt) have been prepared and characterized. In both the X-ray structures of 1 and 3, two crystallographically independent complex molecules were found that differ either in the nature of weakly metal-binding species (water in 1a and nitrate in 1b) or in the co-ligand (water in 3a and methanol in 3b). Electron Paramagnetic Resonance (EPR) measurements carried out on complexes 1 and 3 confirmed the presence of such different species in the solution. The electrochemical behavior of the pro-ligands and of the complexes was investigated, as well as their biological activity. Complexes 2 and 3 exhibited a high cytotoxicity against human tumor cells and 3D spheroids derived from solid tumors, related to the high cellular uptake. Complexes 2 and 3 also showed a high selectivity towards cancerous cell lines with respect to non-cancerous cell lines and were able to circumvent cisplatin resistance. Via the Transmission Electron Microscopy (TEM) imaging technique, preliminary insights into the biological activity of copper complexes were obtained.

Unprecedented formation of palladium(II)-pyrazole based thiourea from chromone thiosemicarbazone and [PdCl2(PPh3)2]: Interaction with biomolecules and apoptosis through mitochondrial signaling pathway

Two novel pyrazole based thiourea palladium(II) complexes, [PdCl(PPh₃)(C₉H₈NO₂S-pz)] (1) and [PdCl(PPh₃)(C₁₄H₁₀NO₂S-pz)] (2) [pz = pyrazole (C₃H₂N₂)] have been obtained unexpectedly from chromone thiosemicarbazones (L1 and L2) and [PdCl₂(PPh₃)₂]. The compounds have been fully characterized by physicochemical studies. The single crystal X-ray diffraction and spectral studies revealed square planar geometry for the complexes. The conversion of chromone thiosemicarbazone into pyrazole based thiourea might have happened through coordination to palladium(II) ion after enolization, Michael addition and ring opening followed by cyclization. To the best of our knowledge, this is the first report for the conversion of chromone thiosemicarbazone into pyrazole based thiourea moiety. Plausible mechanism was proposed based on the spectroscopic studies. Calf thymus (CT) DNA binding of the compounds was explored using various spectroscopic and molecular docking methods. DNA cleavage studies suggested that complexes 1 and 2 had the capacity to cleave the supercoiled DNA (pUC19) to its naked form. In vitro cytotoxic property of the ligands and complexes has been evaluated against three human cancer cells such as A549, HepG-2 and U937. Complex 2 exhibited potent cytotoxic activity against HepG-2 cells with the IC₅₀ value of 10.4 μM. In addition, mechanistic studies showed that complex 2 induced apoptosis through mitochondrial signaling pathway in HepG-2 cells. Beneficially, complex 2 showed less toxicity against human lung (IMR90) normal cells and hence it emerges as a potential candidate for further studies.

para metallation of 3-acetyl-chromen-2-one Schiff bases in tetranuclear palladacycles: focus on their biomolecular interaction and in vitro cytotoxicity

Three tetranuclear (1-3) complexes and a mononuclear (4) palladium(ii) complex were synthesized from 3-acetyl-chromen-2-one Schiff base ligands [H₂-3MAC-Rtsc] (where R = H [H₂-3MAC-tsc]; CH₃[H₂-3MAC-mtsc]; C₂H₅[H₂-3MAC-etsc] or C₆H₅[H₂-3MAC-ptsc]) and potassium tetrachloropalladate. Their formation was confirmed by spectroscopic techniques and X-ray crystallographic analysis. Their ability to bind with DNA and albumin was analysed by using absorption and emission titrations. The MTT assay was carried out to analyze the anticancer potential of the ligands and synthesized complexes against HepG2 (human liver cancer) and HT-29 (human colon cancer) cells. In addition, the compounds were less toxic when tested against the human normal keratinocyte cells (HaCaT). Ligands and complexes displayed better cytotoxicity with lower IC₅₀ values than the standard drug cisplatin. Further AO-EB and DAPI staining assays were carried out to detect the mode of cell death induced by the complexes i.e. apoptosis or necrosis. The complex 3 showed better cytotoxicity and was further subjected to flow cytometric analysis. The results suggested that the complex 3 induced apoptotic cell death.

NHC-catalyzed green synthesis of functionalized chromones: DFT mechanistic insights and in vitro activities in cancer cells

A simple green protocol for the synthesis of 3-aminochromone derivatives using a NHC catalyzed intramolecular hydroacylation reaction was developed. Further functional 3-aminochromes were evaluated for their anticancer activity.

Highly active copper(i) complexes of aroylthiourea ligands against cancer cells – synthetic and biological studies

Copper(i) complexes containing sulfur donor monodentate aroylthiourea ligands have been synthesized and evaluated for their biological applications.