Synthesis of series of different imidazolidine-2,4-dione derivatives and evaluation of their antimicrobial potential

A series of twenty two different imidazolidine-2,4-dione derivatives, divided according to their structure into five groups, including alkyl, alkenyl or aryl 5,5disubstituted hydantoins, spirohydantoins, and fused bicyclic and tricyclic hydantoins, was synthesized and examined for in vitro antimicrobial activity against 15 strains of bacteria and 4 strains of yeast. The antimicrobial activity was evaluated by the determination of the minimal inhibitory concentration (MIC) and the minimal microbicidal concentration (MMC) using the microdilution method. The assayed compounds exerted moderate antibacterial and weak antifungal activity. The antimicrobial activities were influenced by the structure and concentration of the tested compounds as well as the type of test microorganisms. The fused bicyclic hydantoin derivatives obtained by organoselenium induced intramolecular cyclization exhibited the highest inhibitory activity. The examined hydantoin derivatives seem as drug-like candidate for further evaluation of biological activities.Publishe

Антикорозиона активност деривата шифових база 2-тиохидантоина за меки челик у 0,5 m hcl

Several 2-thiohydаntоin–Shiff base derivatives were prepared as ecofriendly corrosion inhibitors for mild steel in acid environment. Their anticorrosion properties were studied on mild steel in 0.5 M HCl solution as corrosion electrolyte by using usuаl grаvimеtriс and different elесtrосhemicаl techniques (wеight lоss mеаsurеmеnt, pоtеntiоdynаmiс pоlаrizаtiоn and pоtеntiоstаtiс еlесtrосhеmicаl impеdаnсе sресtrоscору). Mild steel surface was characterized using two analytical techniques, scanning electron microscopy for surface morphology and elemental composition and atomic force microscopy. The study has shown that the inhibiting action of these environmentally benign inhibitors synthesized from inexpensive commercially available starting materials could be attributed to adsorption on the metal surface.Неколико деривата Шифових база 2-тиохидантоина су направљени као еколошки прихватљиви инхибитори корозије меког челика у киселој средини. Њихова антикорозиона својства су испитана на меком челику у 0,5 M раствору HCl као корозионом електролиту, користећи уобичајене гравиметријске и различите електрохемијске технике (мерење губитка масе, потенциодинамичка поларизација, потенциостатска спектроскопија електрохемијске импеданције). Површина меког челика је окарактерисана двема аналитичким техникама, скенирајућом електронском микроскопијом за морфологију површине и елементарни састав и микроскопијом атомске силе. Студија је показала да се инхибиторно деловање ових еколошки бенигних инхибитора, синтетисаних из јефтиних комерцијално доступних полазних материјала, може приписати адсорпцији инхибитора на површини меког челика

Electrochemical investigation of 2-thiohydantoin derivatives as corrosion inhibitors for mild steel in acidic medium

Four 2-thiohydantoin derivatives were synthesized and their corrosion inhibition properties on mild steel (MS) in 0.5M HCl solution was evaluated using usual gravimetric and electrochemical methods (weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS). Morphology of the metal surface was characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The study has shown that these compounds provide good protection for mild steel against corrosion in the acidic medium

Dynamic and Assembly Characteristics of Deep-Cavity Basket Acting as a Host for Inclusion Complexation of Mitoxantrone in Biotic and Abiotic Systems

We describe the preparation, dynamic, assembly characteristics of vase-shaped basket 13− along with its ability to form an inclusion complex with anticancer drug mitoxantrone in abiotic and biotic systems. This novel cavitand has a deep nonpolar pocket consisting of three naphthalimide sides fused to a bicyclic platform at the bottom while carrying polar glycines at the top. The results of 1H Nuclear Magnetic Resonance (NMR), 1H NMR Chemical Exchange Saturation Transfer (CEST), Calorimetry, Hybrid Replica Exchange Molecular Dynamics (REMD), and Microcrystal Electron Diffraction (MicroED) measurements are in line with 1 forming dimer [12]6−, to be in equilibrium with monomers 1(R)3− (relaxed) and 1(S)3− (squeezed). Through simultaneous line-shape analysis of 1H NMR data, kinetic and thermodynamic parameters characterizing these equilibria were quantified. Basket 1(R)3− includes anticancer drug mitoxantrone (MTO2+) in its pocket to give stable binary complex [MTO⊂1]− (Kd=2.1 μM) that can be precipitated in vitro with UV light or pH as stimuli. Both in vitro and in vivo studies showed that the basket is nontoxic, while at a higher proportion with respect to MTO it reduced its cytotoxicity in vitro. With well-characterized internal dynamics and dimerization, the ability to include mitoxantrone, and biocompatibility, the stage is set to develop sequestering agents from deep-cavity baskets

Synthesis of Angularly Fused (Homo)triquinane-Type Hydantoins as Precursors of Bicyclic Prolines

© Georg Thieme Verlag Stuttgart · New York-Synthesis 2016. An efficient strategy for a four-step synthesis of angularly fused tricyclic hydantoins as suitable precursors of cis-fused bicyclic α-amino acids is developed by combining a highly diastereoselective Bucherer-Bergs reaction of 2-alkenylcycloalkanones and a regiospecific selenium-induced closure of pyrrolidine ring. This methodology was applied in a five-step synthesis of bicycloproline derivatives in high overall yield. The method could be used for the multigram preparation of free conformationally constrained bicyclic α-amino acids with two points of diversity (size of cycloalkyl ring and substituent at the pyrrolidine ring)

Mechanism, kinetics and selectivity of selenocyclization of 5-alkenylhydantoins: An experimental and computational study

© 2015 Šmit et al. The mechanism and selectivity of a bicyclic hydantoin formation by selenium-induced cyclization are investigated. The proposed mechanism involves the intermediates formed by an electrophilic addition of the selenium reagent on a double bond of the starting 5-alkenylhydantoin prior the cyclization. These intermediates are readily converted into the more stable cyclic seleniranium cations. A key step of the mechanism is an intramolecular cyclization which is realized through an anti-attack of the internal nucleophile, the amidic nitrogen, to the seleniranium cation yielding the intermediate imidazolinium cations. Their deprotonation is followed by the formation of the fused bicyclic reaction products. Important intermediates and key transition states are studied by using density functional theory (DFT) methods. The pathways of the reaction are investigated in detail. There are two regioselective pathways related to 5-exo and 6-endo products. Theoretical calculations and the monitoring of the cyclization reaction using 1H NMR spectroscopy are in a good agreement with the proposed mechanism and are consistent with our experimental results. The preferred pathway for formation of 5-exo products is confirmed

Influence of electrochemical conditions on the regio- And stereoselectivity of selenocyclization of alkenyl hydantoins

5-Alkenyl hydantoins and alkenyl spirohydantoins are converted into bicyclic and tricyclic hydantoins, under indirect electrochemical conditions, generating the phenylselenyl cation in situ. The reactions proceeded in good to exelent yields. The influence of electrochemical conditions on regio- and diastereoselectivity of the selenocyclization reactions is investigated

Novel seleno-hydantoin palladium(II) complex - antimigratory, cytotoxic and prooxidative potential on human colon HCT-116 and breast MDA-MB-231 cancer cells

Selenium and palladium containing compounds separately exert multifunctional effects on cells. While selenium containing compounds usually exert antioxidative properties, palladium(II) containing compounds are cytotoxic and prooxidative. Here we investigated biological effects of bicyclic seleno-hydantoin cis-7a-ethyl-5-methyl-5-phenylselanylmethyl-tetrahydro-pyrrolo[1,2-c] imidazole-1,3-dione (Hid-Se), and its palladium(II) complex, trans-bis-(cis-7a-ethyl-5-methyl-5-phenylselanylmethyl-tetrahydro-pyrrolo[1,2-c]imidazole-1,3-dionato) palladium(II) chloride ((Hid-Se)2Pd) on human colon HCT-116 and breast MDA-MB-231 cancer cell lines. Hid-Se and (Hid-Se)2Pd showed prooxidative and cytotoxic character. In all performed experiments (Hid-Se)2Pd proved to be more active, i.e. this substance exerted greater prooxidative effect, cytotoxicity and influence on cell migration potential. Even though Hid-Se and (Hid-Se)2Pd enhanced migration of HCT-116 cells, very important feature of these substances is the strong antimigratory potential on metastatic MDA-MB-231 cells

Synthesis, characterization, DFT study, DNA/BSA-binding affinity, and cytotoxicity of some dinuclear and trinuclear gold(III) complexes

Abstract: In this study, we have synthesized a series of dinuclear and trinuclear gold(III) complexes of the general formula [Au2(N–N)Cl6] (1–3) for dinuclear and [Au3(N–N)2Cl8]+ (4–6) for trinuclear compounds, respectively, in which N–N is a bidentate ligand (1,4-diaminobutane; 1,6-diaminohexane or 1,8-diaminooctane). These complexes were characterized by elemental analysis, molar conductivity, and spectroscopic techniques (IR, UV–Vis, 1H NMR, ESI–MS). We performed DFT calculations to get insight into the geometry of the studies complexes. DNA-binding studies were performed by UV–Vis spectrophotometry and fluorescence spectroscopy. The results of competitive reactions between gold(III) complexes and ethidium bromide (EB) towards DNA have shown that selected complexes can displace EB from DNA-EB adduct. In addition, these experiments confirm that polynuclear gold(III) complexes interact with DNA covalently or via intercalation. Furthermore, high values of binding constants of gold(III) complexes towards bovine serum albumin (BSA) protein indicate good binding affinity. In addition, redox stability of complexes in the presence of DNA/BSA was confirmed by cyclic voltammetry. Results of the interactions between gold(III) complexes with DNA/BSA were discussed in reference to molecular docking data obtain by Molegro virtual docker. The cytotoxic activity of synthesized gold(III) complexes was evaluated on human breast cancer cell line (MDA-MB-231), human colorectal cancer cell line (HCT-116), and normal human lung fibroblast cell line (MRC-5). All complexes dose-dependently reduced cancer and normal cells viabilities, with significant cytotoxic effects (IC50 < 25 μM) for trinuclear gold(III) complexes (4, 5) on HCT-116 cells. Graphic abstract: [Figure not available: see fulltext.]

Bis(triazinyl)pyridine complexes of Pt(II) and Pd(II): studies of the nucleophilic substitution reactions, DNA/HSA interactions, molecular docking and biological activity

Four new complexes of Pt(II) and Pd(II), [Pd(L1)Cl]Cl 1, [Pd(L2)Cl]Cl 2, [Pt(L1)Cl]Cl 3 and [Pt(L2)Cl]Cl 4 (where L1 = 2,6-bis(5,6-diphenyl-1,2,4-triazin-3-yl)pyridine and L2 = 2,6-bis(5,6-dipropyl-1,2,4-triazin-3-yl)pyridine), were synthesized. Characterization of the complexes was performed using elemental analysis, IR, 1H NMR spectroscopy and MALDI-TOF mass spectrometry. The substitution reactions of 1-4 complexes with L-methionine (L-met), L-cysteine (L-cys) and guanosine-5'-monophosphate (5'-GMP), were studied spectrophotometrically at physiological conditions. Complexes with ligand L1 (1 or 3) were more reactive than those with ligand L2 (2 or 4) by a factor ranging up to 1.57 and 3.71, respectively. The order of reactivity of the nucleophiles was: L-met > L-cys > 5'-GMP. The interactions of complexes with calf thymus-DNA (CT-DNA) and human serum albumin (HSA) were studied by Uv-Vis absorption and fluorescence emission spectroscopy. Competitive binding studies with intercalative agent ethidium bromide (EB) and minor groove binder Hoechst 33258 were performed as well. All studied complexes can interact with DNA through the intercalation and minor groove binding, where the latter was preferred. The binding constants (103 and 104 M-1) for the interaction of complexes with HSA indicate the moderate binding affinity of complexes 1-4 to protein. The trends in the experimental results of binding studies between complexes 3 and 4 with DNA and HSA were compared to those obtained from the molecular docking study. Biological evaluation of cytotoxicity of 1 and 2 on HCT-116 and MDA-MB-231 cell lines showed significant cytotoxic and prooxidative character, while 2 also exerted extraordinary selectivity towards colon cancer in comparison to breast cancer cells. The nucleophilic substitution reactions, DNA/HSA interactions, molecular docking and biological activity of bis(triazinyl)pyridine complexes of Pt(II) and Pd(II) were studied