Synthesis, characterization and in vitro screening for anticancer potential of Mn(II), Co(II), Cu(II), Zn(II), and Pt(II) methoxyphenyl dithiocarbamato complexes

Antiproliferative activity of Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes of dithiocarbamate: synthesis, structural characterization, and thermal studies

Five new metal complexes of Fe(II) (1), Co(II) (2), Ni(II) (3), Cu(II) (4), and Zn(II) (5), derived from an N-cyclohexyl N-(3,4-dimethoxybenzyl) dithiocarbamate ligand, have been successfully synthesized and fully characterized by different analytical techniques i.e. elemental analyses, FT-IR, UV-Vis, 1H & 13C NMR, and HRMS. Furthermore, complexes 4 and 5 have been characterized by the SC-XRD technique. Complex 4 adopts a distorted square planar geometry around the Cu(II) center while complex 5 adopts a distorted tetrahedral geometry around the Zn(II) center. In addition, an eight-membered symmetric chair-like metallacycle ring containing two Zn(II) centers has also been found in complex 5. XRD data also show that complexes 4 and 5 are stabilized by various weak intermolecular hydrogen bonding interactions. The course of the thermal degradation of metal complexes 1-5 has been examined by TG-DTA data which revealed that metal sulphide formed as the final residue. Complexes 1-5 demonstrated concentration-dependent cytotoxicity and growth inhibition of DL tumor cells. Among the compounds, complexes 1, 4, and 5 showed significant cytotoxicity and induced a loss in the viability of DL cells. Therapy with complexes 1, 4, and 5 protects DL tumor-bearing animals from exacerbation of the disease, increases lifespan, and significantly improves the histopathological parameters of the vascularized organ, including preventing metastasis. Overall cytotoxicity assay results indicate that all complexes have remarkable cytotoxic potential in comparison with the free ligand.

Exploring the Interaction Between the Newly Designed Antitumor Zn(II) Complex and CT-DNA/BSA: Spectroscopic Methods, DFT Computational Analysis, and Docking Simulation

A new zinc(II) complex formulated as [Zn(pipr-ac)2], where pipr-ac stands for piperidineacetate, was synthesized and structurally identified with the help of experimental and DFT methods. Frontier molecular orbital (FMO) analysis demonstrated that the new complex has higher biological activity compared to the free ligand. Molecular electrostatic potential (MEP) showed the nitrogen atoms and oxygen of carbonyl groups are the active sites of Zn(II) compound. Also, natural bond orbital (NBO) analysis confirmed the charge transfer from the ligating atoms to the metal ion and formation of four coordinated Zn(II) complex. MTT assay illustrated a noticeable cytotoxic activity of the new zinc(II) complex compared to cisplatin on K562 cell line. The CT-DNA and serum albumin (SA) binding of the Zn(II) complex were explored individually. In this regard, UV-Vis spectroscopy and florescence titration revealed the occurrences of fluorescence quenching of CT-DNA/SA by metal compound via static mechanism and creation of hydrogen bonds and van der Waals interactions between them. The binding was further confirmed by viscosity measurement and gel electrophoresis assay for CT-DNA and circular dichroism spectroscopy for SA. Moreover, molecular docking simulation demonstrated that the new compound binds mainly through hydrogen bonds to the groove of DNA and hydrogen bonds and van der Waals interactions to site I of SA.

Anticancer potential of Cu(II)prolinedithiocarbamate complex: design, synthesis, spectroscopy, molecular docking, molecular dynamic, ADMET, and in-vitro studies

Breast cancer continues to be a major health issue for women all over the world. Cancer medications like cisplatin, which are widely used, still have negative side effects. The novel complex was created as a potential anticancer medication candidate that is both effective and safe, with few side effects. The Cu(II) complex using the prolinedithiocarbamate ligands was synthesized in situ. The Cu(II) complexes Characterization by UV-Vis, FT-IR spectroscopy and melting point determination, conductivity, and HOMO-LUMO were studied. Computational NMR spectrum analysis was performed. The interaction of Cu(II)prolineditiocarbamate complex with cancer cell target protein (MCF-7) was confirmed by molecular docking and molecular dynamic. The pharmacokinetic/ADMET properties were also performed on the complex. Results of the cytotoxic complex test against cancer cells (MCF-7) undergoing apoptosis with an IC50 value of 13.64 µg/mL showed high anticancer activity in MCF-7 cancer cells. The in-vivo data for Cu(II)prolineditiocarbamate complex was predicted using the Protox online tool with an LD50 value of 2500 mg/kg and belonging to the GHS toxicity class 5, which means the compound has a low acute toxicity effect. The Cu(II) prolineitiocarbamate complex may pave the way for the development of essential metal-based chemotherapy for the treatment of breast cancer.Communicated by Ramaswamy H. Sarma.

Assessment of physiological and electrochemical effects of a repurposed zinc dithiocarbamate complex on Acinetobacter baumannii biofilms

Acinetobacter baumannii is an infectious agent of global proportion and concern, partly due to its proficiency in development of antibiotic resistance phenotypes and biofilm formation. Dithiocarbamates (DTC) have been identified as possible alternatives to the current antimicrobials. We report here the evaluation of several DTC-metal complexes against A. baumannii planktonic cells and biofilms. Among the DTC-metal complexes and DTCs tested, ZnL1 (N-methyl-1-phenyldithiocarbamato-S,S' Zn(II)), originally designed as an antitumor agent, is effective against biofilm forming A. baumannii. A MIC value of 12.5 µM, comparable to that of Gentamicin (5 µM) was measured for planktonic cells in tryptic soy broth. Spectroscopy, microscopy and biochemical analyses reveal cell membrane degradation and leakage after treatment with ZnL1. Bioelectrochemical analyses show that ZnL1 reduces biofilm formation and decreases extracellular respiration of pre-formed biofilms, as corroborated by microscopic analyses. Due to the affinity of Zn to cells and the metal chelating nature of L1 ligand, we hypothesize ZnL1 could alter metalloprotein functions in the membranes of A. baumannii cells, leading to altered redox balance. Results indicate that the DTC-Zn metal complex is an effective antimicrobial agent against early A. baumannii biofilms under laboratory conditions.

Complexes of Zn(II) with a mixed tryptanthrin derivative and curcumin chelating ligands as new promising anticancer agents

In this study, two novel curcumin (H-Cur)-tryptanthrin metal compounds-[Zn(TA)Cl₂], i.e., Zn(TA), and [Zn(TA)(Cur)]Cl, i.e., Zn(TAC)-were synthesized and investigated using 5-(bis-pyridin-2-ylmethyl-amino)-pentanoic acid (6,12-dioxo-6,12-dihydro-indolo[2,1-b]quinazolin-8-yl)-amide (TA) and H-Cur as the targeting and high-activity anticancer chemotherapeutic moieties, respectively. They were then compared with the di-(2-picolyl)amine (PA) Zn(II) complex [Zn(PA)Cl₂], i.e., Zn(PA). When compared with Zn(PA) and cisplatin, the IC₅₀ values of Zn(TA) and Zn(TAC) indicated that the compounds had high cytotoxicity against A549/DDP cancer cells, implying that the H-Cur-tryptanthrin Zn(II) compounds have the potential for use as anticancer drugs. We propose the use of synthesized theragnostic H-Cur-tryptanthrin Zn(II) complexes with nuclear-targeting and DNA-damaging capabilities as a simple therapeutic strategy against tumors. The Zn(TA) and Zn(TAC) complexes could be traced via red fluorescence and were found to accumulate in the cell nuclei and induce DNA damage, cell cycle arrest, mitochondrial dysfunction, and cell apoptosis both in vitro and in vivo. In addition, Zn(TAC) exhibited a higher antiproliferative effect on A549/DDP than Zn(TA) and Zn(PA), which was undoubtedly associated with the key roles of the novel tryptanthrin derivative TA and H-Cur in the Zn(TAC) complex.

Bis(N-picolinamido)cobalt(II) Complexes Display Antifungal Activity toward Candida albicans and Aspergillus fumigatus

This report highlights the synthesis and characterization of ten new bis(N-picolinamido)cobalt(II) complexes of the type [(L)2 CoX2 ]0/2+ , whereby L=N-picolinamide ligand and X=diisothiocyanato (-NCS), dichlorido (-Cl) or diaqua (-OH2 ) ligands. Single crystal X-ray (SC-XRD) analysis for nine of the structures are reported and confirm the picolinamide ligand is bound to the Co(II) center through a neutral N,O binding mode. With the addition of powder X-ray diffraction (PXRD), we have confirmed the cis and trans ligand arrangements of each complex. All complexes were screened against several fungal species and show increased antifungal activity. Notably, these complexes had significant activity against strains of Candida albicans and Aspergillus fumigatus, with several compounds exhibiting growth inhibition of >80 %, and onecompound inhibiting Aspergillus fumigatus hyphal growth by >90 %. Conversely, no antifungal activity was exhibited toward Cryptococcus neoformans and no cytotoxicity towards mammalian cell lines.

4-(((4-Methoxyphenyl)amino)methyl)-N,N-dimethylaniline and 2-Methoxy-5-((phenylamino)methyl)phenol

Molecular structures of 4-(((4-methoxyphenyl)amino)methyl)-N,N-dimethylaniline and 2-methoxy-5-((phenylamino)methyl)phenol synthesized via Schiff bases reduction route are reported. The compounds consist of asymmetric units of C16H20N2O (1) and C14H15NO2 (2) in orthorhombic and monoclinic crystal systems, respectively. Compound 1 consist of intermolecular C11—H11···N2 hydrogen bonding with C11···N21 = 3.463(4) Å. The hydroxyl group in 2 is also involved in intermolecular O2—H2···O2 and O2—H2···O21 hydrogen bonding with O2···O11 = 2.8885(15) Å and O1···O21 = 2.9277(5) Å. The molecular structures of the compounds are stabilized by secondary intermolecular interactions of C1—H1B···O11 and C5—H···(C41, C51, C61, C71) for 1 and H···C, C—H···O and N—H···C for 2. The reported compounds are important starting material for the synthesis of many compounds such as azo dyes and dithiocarbamate.