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Carbon monoxide, the "silent killer" gas, is increasingly recognised as an important signalling molecule in human physiology, which has beneficial biological properties. A particular way of achieving controlled CO administration is based on the use of biocompatible molecules that only release CO when triggered by internal or external factors. These approaches include the development of pharmacologically effective prodrugs known as CO releasing molecules (CORMs), which can supply biological systems with CO in well-regulated doses. An overview of transition metal-based CORMs with cytotoxic properties is here reported. The mechanisms at the basis of the biological activities of these molecules and their potential therapeutical applications with respect to their stability and CO releasing properties have been discussed. The activation of metal-based CORMs is determined by the type of metal and by the nature and features of the auxiliary ligands, which affect the metal core electronic density and therefore the prodrug resistance towards oxidation and CO release ability. A major role in regulating the cytotoxic properties of these CORMs is played by CO and/or CO-depleted species. However, several mysteries concerning the cytotoxicity of CORMs remain as intriguing questions for scientists. [ABSTRACT FROM AUTHOR]

A series of Pd(II) complexes of the general formula [PdX(NNS)] (X = Cl, Br, I, NCS and phenyl-tetrazole-thiolato; NNS = 2-quinolinecarboxyaldehyde-N4-phenylthiosemicarbazone) was tested against four malignant cell lines for their antiproliferative properties and the outcomes were compared to those seen in normal mouse splenocytes. Various auxiliary ligands were substituted in order to investigate the impact of the character of the ligand on the cytotoxicity of this class of Pd(II) complexes. The iodo complex was the most cytotoxic compound towards the Caco-2 cell line in this study. The improved apoptosis and necrosis cell modes were in accordance with the fragmentation results of DNA, which revealed increased fragmentation terminals, especially in isothiocyanate and tetrazole-thiolato complexes. After 24 hours, at half the IC50 of each complex, the complex-treated cells exhibited considerable genotoxicity when compared to the corresponding non-treated control especially in the case of isothiocyanate and tetrazole-thiolato complexes. [ABSTRACT FROM AUTHOR]

Human acute monocytic leukaemia cells were tested under both dark and light conditions for their susceptibility to Mn(I) and Ru(II) carbonyl complexes with a diphenyl pyridyl phosphine coligand. The Ru(II) complex (IC50 = 7.13 ± 0.8 μM) displayed higher outstanding potency against leukaemia than the Mn(I) analogue (54.58 ± 4.1 μM) in the dark and both complexes were completely harmless to healthy mouse bone marrow cells. [ABSTRACT FROM AUTHOR]

Objective: To assess the safety and feasibility of robot‐assisted retroperitoneal lymph node dissection (R‐RPLND) and to compare the perioperative outcomes of R‐RPLND with open RPLND (O‐RPLND), as RPLND forms an integral part of the management of testis cancer and R‐RPLND is a minimally invasive treatment option for this disease. Materials and Methods: The PubMed®, Scopus®, Cochrane Central Register of Controlled Trials, and Web of Science™ databases were searched for studies reporting perioperative outcomes of primary and post‐chemotherapy R‐RPLND and studies comparing R‐RPLND with O‐RPLND. Results: The search yielded 42 articles describing R‐RPLND, including five comparative studies. The systematic review included 4222 patients (single‐arm studies, n = 459; comparative studies, n = 3763). Of 459 patients in the single‐arm studies, 271 underwent primary R‐RPLND and 188 underwent post‐chemotherapy R‐RPLND. For primary R‐RPLND, the operative time ranged from 175 to 540 min and the major complication rate was 4.1%. For post‐chemotherapy R‐RPLND, the operative time ranged from 134 to 550 min and the major complication rate was 8.5%. The conversion rate to open surgery was 2.2% in primary R‐RPLND and 9.0% in post‐chemotherapy R‐RPLND. In comparison with O‐RPLND, R‐RPLND was associated with a lower transfusion rate (14.5% vs 0.9%, P < 0.001) and a lower complication rate (18.5% vs 7.8%, P = 0.002). Conclusion: Robot‐assisted RPLND has acceptable perioperative outcomes in both the primary and post‐chemotherapy settings but a notable rate of conversion to open surgery in the post‐chemotherapy setting. Compared with O‐RPLND, R‐RPLND is associated with a lower transfusion rate and fewer overall complications. Given the potential impact of selection bias, the optimal patient selection criteria for R‐RPLND remain to be elucidated. [ABSTRACT FROM AUTHOR]

[Display omitted] • The triazolate Pd(II) complex binds to lysozyme via the loss of triazolato ligand. • Agreement between the experimental and theoretical studies regarding the high stability of N2 triazolate complex over the N1 and N3 analogues. • Triazolate complexes exhibited comparable selective antifungal activity to reference drug. • The complexes are safe to normal cell line and are compatible with the red blood cells. Modern classes of antimicrobials are crucial because most drugs in development today are basically antibiotic derivatives. Even though a large number of metal-based compounds have been studied as antimicrobial agents, relatively few studies have examined the antimicrobial properties of Pd(II) and Pt(II) compounds. The [3+2] cycloaddition reactions of [M(N 3)L]PF 6 (M = Pd(II) and Pt(II); L = 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine) with 4,4,4-trifluoro-2-butynoic acid ethyl ester gave the corresponding triazolate complexes. The reaction products were fully characterized with a variety of analytical and spectroscopic tools including X-ray crystallographic analysis. The crystal structure of [Pd(triazolatoCF3,COOCH2CH3)L]PF 6 provided cut-off evidence that the kinetically formed N1-triazolato isomer favoured the isomerization to the thermodynamically stable N2-analogue. The experimental work was complemented with computational work to get an insight into the nature of the predominant triazolate isomer. The lysozyme binding affinity of the triazolate complexes was examined by mass spectrometry. An analysis of the lysozyme Pd(II) adducts suggests a coordinative covalent mode of binding via the loss of the triazolato ligand. The free ligand and its triazolate complexes displayed selective toxicity against Candida albicans and Cryptococcus neoformans , while no cytotoxicity was observed against the normal human embryonic kidney cell line. [ABSTRACT FROM AUTHOR]

Introduction of the propyl-sulfonic acid group at N1 of the coordinated 2-(2-pyridyl)benzimidazole ligand (L) in [RhCl(η5-C5Me5)L](CF3SO3) gives rise to a water-soluble complex, which can bind to the model protein lysozyme via non-covalent interactions. The complex shows selective moderate toxicity against Cryptococcus neoformans (MIC = 21.6–43.3 μM) and exhibits no cytotoxicity to healthy HEK293 cells. [ABSTRACT FROM AUTHOR]

Reaction between bromo tricarbonyl manganese(I) and N,N′-bis(phenyl)-1,4-diaza-1,3-butadiene ligands, bearing different electron-donating and electron-withdrawing groups R = OCH3, Cl, and NO2 in the ortho- and para-positions on the phenyl substituent, afforded [MnBr(CO)3(N–N)] complexes. The influence of the character and position of the substituent on the dark stability and carbon monoxide releasing kinetics was systematically investigated and correlated with the data of the time-dependent density functional theory calculations. The combined UV/Vis and IR data clearly revealed that the aerated solutions of [MnBr(CO)3(N–N)] in either coordinating or noncoordinating solvents are dark stable and the fluctuations observed during the incubation period especially in the case of the nitro derivatives may be attributed to the exchange of the axial bromo ligand with the coordinating solvent molecules. The free ligands and nitro complexes were non-cytotoxic to HepG2 cells under both the dark and illumination conditions. In the dark, Mn(I) compounds, incorporating o-OCH3 and o-Cl, exhibited excellent cytotoxicity with IC50 values of 18.1 and 11.8 μM, while their para-substituted analogues were inactive in the dark and active upon the irradiation at 365 nm with IC50 values of 5.7 and 6.7 μM, respectively. [ABSTRACT FROM AUTHOR]

The lysozyme binding affinity and the electronic properties of [ReX(CO)3(terpy-κ2N1,N2)] (X = Br− and triazolateCOOCH2CH3,CF3) were reported. The triazolate complex was prepared in a [3 + 2] cycloaddition click reaction. The bromo compound reacted with lysozyme affording adducts with Re(CO)3+ fragments, while the triazolate compound persisted. A red shift of the MLCT band of the triazolate compound in progressively less polar solvents may be due to the negative solvatochromism. [ABSTRACT FROM AUTHOR]

Men are more susceptible to liver fibrosis (LF) than women. However, the underlying molecular mechanism, especially the role of estrogen/estrogen receptor (ER) activation in this sexual dimorphism is unclear. Therefore, the aim of the current study was to investigate the impact and the underlying molecular mechanisms of estrogen/ER activation on diethyl nitrosamine (DEN)-induced LF. Thirty ovariectomized (OVX) female rats were randomly allocated into five groups (n = 6), and received no treatment, diethyl nitrosamine (DEN), DEN/fulvestrant, DEN/silymarin or DEN/estradiol benzoate (EB). In addition, three sham groups received no treatment, DEN or DEN/fulvestrant, and one control group that neither ovariectomized nor treated. Directly after treatment, liver injury biomarkers were measured. In addition, hepatic tissue hydroxyproline, TNF- α, TGF- β, and IL-10 were evaluated. Expression of NF -kβ , CD68 (a marker for macrophage infiltration), ER-β and TLR-4 were measured. Finally, liver tissue histopathology was assessed. Ovariectomy aggravates DEN-induced LF, as it significantly elevated all liver tissue injury biomarkers. This effect has become even worse after blocking ER by fulvestrant, indicating a protective role of estrogen/ER activation against DEN-induced LF. Inhibition of TLR-4/NF -kβ signaling pathway contributed to this protective effect, as estrogen deprivation or blocking of ER significantly activates this pathway during the onset of LF. While administration of EB or silymarin (selective ER-β activator) improved LF indices and deactivated this pathway. These results provide new insight into the pivotal role of estrogen/ER activation via modulation of TLR-4/NF -kβ , in the alleviation of LF pathogenesis. [ABSTRACT FROM AUTHOR]

Similar to the antibiotic mixing strategies, which depend on reducing the worth of diffusion of the resistant bacteria to new host, in this contribution, we explicit new mixed‐ligand complexes of the type [M(SMZ)2(BZM)] (M = Co(II), Ni(II) and Cu(II)) based on two drugs: sulfamethazine (SMZ) and bromazepam (BZM). The novelty aspect of the present work relies on combining two drugs in a single molecule via the synthesis of the ternary complexes. The ternary complexes were characterized by spectroscopic and analytical tools with the aid of the quantum chemical calculations. Copper(II) complex has the highest DNA intrinsic binding constant (2.20 × 105 M−1), induces extensively DNA cleavage compared to the other complexes, and exhibits the highest cytotoxicity (IC50 = 0.67 μM) against human liver cancer cell line (HepG2). Exciting, Cu(II) compound exhibits no toxicity to the nonmalignant human foetal lung fibroblast (WI‐38). Alternatively, the low cytotoxicity of the Co(II) complex correlates well with the high affinity of the compound to human serum albumin (Kb = 4.58 × 105) compared to 1.93 × 105 and 2.14 × 105 M−1 for Ni (II) and Cu (II) complexes, respectively. [ABSTRACT FROM AUTHOR]

Reaction between 2-(2′-pyridyl)benzimidazole derivatives and [{IrCl(η5-C5Me5)}2(μ-Cl)2] afforded mono- and binuclear "piano-stool" Ir(III) compounds of type [IrnCln(η5-C5Me5)n(L)]Cln (n = 1, L = LET (1) and LSO3H (2); n = 2, L = LBN (3)), which were fully characterized, including the X-ray crystallographic analysis of 1. While the free ligands and compound 3 exhibited no toxicity to the tested microbes, compound 1 was highly potent against bacteria (MIC = 12.9–25.8 nM) and fungi (MIC < 0.40 nM). However, complex 1 induced damage to non-malignant cell lines (human embryonic kidney (HEK293), CC50 = 0.995 μg mL−1) and human RBCs (HC10 = 10.9 μg mL−1 and HC50 > 32 μg mL−1). Interestingly, complex 2, bearing the benzimidazole ligand with an alkylated sulfonate side chain (LSO3H), was selectively potent against C. neoformans with MIC value of 11.2 nM and was non-toxic to HEK293. According to DNA binding studies, compounds 1–3 could be considered as moderate metallo intercalators with a binding constant of 5.0 × 104–1.0 × 105 M−1. Alternatively, evidence was obtained, from ESI-MS measurements, for the non-covalent mode of binding of 2 to hen egg white lysozyme, while compounds 1 and 3 decomposed during the interaction with that protein. This may be attributed to the electrostatic and H-bonding interactions between the polar sulfonate group and charged protein side-chains. [ABSTRACT FROM AUTHOR]

Mono‐ and binuclear benzimidazole based half‐sandwich organoruthenium(II) compounds; [Run(triazolateCOOCH3,COOCH3)n(η6‐p‐Cym)nL]0/+/2+ (n = 1, L = LCH2CH3 (7) and HLSO3H (8); n = 2, L = LDTP (9)) were synthesized by [3+2] free catalyzed cycloaddition reaction of azide complexes 4–6 with electron‐poor alkyne dimethyl acetylene dicarboxylate. In comparison with the parent [RunCln(η6‐p‐Cym)nL]0/+/2 complexes (1–3), the lysozyme binding affinity of the corresponding triazolate compounds 7–9 was investigated by electrospray ionization mass spectrometry. Complexes bearing benzimidazole ligand with an alkylated sulfonate side chain (2 and 8) are able to bind lysozyme noncovalently, which have not been clearly seen by other investigated Ru(II) complexes. The complexes were assessed for their potential antimicrobial activity against some representative microbes. Complex 9 exhibits antifungal activity against C. albicans (MIC = 24 nm) and C. neoformans (MIC = 12 nm), perfect blood compatibility as well as no toxicity to non‐malignant cell line (human embryonic kidney cells (HEK293). [ABSTRACT FROM AUTHOR]

A series of photoactivatable CO‐releasing molecules (PhotoCORMs) was prepared from manganese pentacarbonyl bromide and 1H‐benzimidazol‐2‐ylmethyl‐(N‐phenyl)amine ligands (L) bearing different electron‐donating and electron‐withdrawing groups R = H, 4‐CH3, 4‐OCH3, 4‐Cl, 4‐NO2, 2‐, 3‐, and 4‐COOCH3 on the phenyl substituent to give octahedral manganese(I) complexes of the general formula [MnBr(CO)3(L)]. Aerated DMSO solutions of the compounds are stable in the dark for 16 h with no CO release. However, the compounds rapidly release CO upon illumination at 412–525 nm, depending on the substitution pattern. Its influence on the photophysical and photochemical properties was systematically explored using UV/Vis spectroscopy and CO release measurements with a commercial gas sensor system. In the nitro‐substituted compound, the electronically excited state switched from benzimidazole‐ to phenyl‐centered, leading to a markedly different photochemical behavior of this visible‐light activated PhotoCORM. [ABSTRACT FROM AUTHOR]

Photostable mono‐ and binuclear silver(I) complexes derived from terpyridine ligands (4′‐(2‐pyridyl)‐2,2′:6′,2′′‐terpyridine (LPY) (1), 4′‐(4‐phenyl morpholine)‐2,2′:6′,2′′‐terpyridine (Lmorph) (2) and 1,4‐bis (2,2′:6′,2′′‐terpyridin‐4′yl) benzene (LDB) (3)) were synthesized and fully characterized in the solution and solid‐state including [1H–15N] heteronuclear multiple bond coherence (HMBC) NMR analysis and single‐crystal X‐ray analysis of five‐coordinates [Ag2(LPY)2(CH3CN)2](SO3CF3)2. Based on the NMR and ESI‐MS data, complex 1 exists as dimeric species, formed by head‐to‐tail interaction, while monomeric species of 3 predominantly exist in the same solvents. The protein binding affinity of 1–3 was investigated by using hen white egg lysozyme (HEWL). To explore where the metalation site of HEWL is, the interactions between the complexes and histidine were studied by NMR. The morpholine ligand and its Ag(I) complex (2) exhibited interesting antimicrobial activity. In comparison with AgOSO2CF3, compounds 1–3 displayed lower cytotoxicity to non‐malignant human embryonic kidney (HEK293) cells, and induced negligible haemoglobin release. [ABSTRACT FROM AUTHOR]

[Display omitted] • Strong autofluorescence emission can be seen in our Re(I) complexes. • Re(I) complexes build up around cellular membranes and within intercellular connections as they wait to enter, as evidenced by the fluorescence microscopy. • Cytotoxicity is related to the nature of the substituent on the phenyl ring. • DNA fragmentation data were complying to results of MTT and mode of cell death. Four tricarbonyl rhenium(I) complexes featuring quinoline ligands (1 – 4) were examined for their potential cytotoxicity properties against three malignant cell lines and one normal cell line of different origins. The most cytotoxic compound among the synthesized complexes was complex 2 , which was formed when [ReBr(CO) 3 (N∧O)] (N∧O = quinoline-2-carboxaldehyde) (1) and para -amino phenol reacted. Its IC 50 values are in the range of 26.05–30.33 μg/mL. Complex 4 , decorated with benzimidazole moiety, has been demonstrated to be harmless to normal mice splenocytes. The cellular localization of 1 – 4 was investigated using fluorescence microscopy to provide insight into their biotargets, cellular localization, and modes of action. Among the evaluated malignant cell lines, complex 2 exhibited the highest levels of apoptotic and necrotic alterations in the MCF-7 cell line. Re(I) complexes appeared to gather inside intercellular connections and around cellular membranes, as seen in the fluorescence microscopy images. Along the cell membrane, the compounds accumulated as well, anticipating their entry. [ABSTRACT FROM AUTHOR]

The lysozyme binding affinity of new Au(III) complexes, bearing pyridylbenzimidazole ligands, was investigated by ESI‐MS and UV/Vis. Metalation of lysozyme happened mainly by {Au}n+, {AuCl}0/n+ and {AuCl2}n+/–. The appendage sulfonate group of pyridylbenzimidazole ligand system played a role in determining the products of interaction of HEWL with Au(III) complexes. The hydrophilic sulfonate group inhibited the ligand cleavage via the participation in several coulombic and H‐bond interactions giving several AuLn+ containing adduct peaks (L = 1‐[(pyridin‐2‐yl) benzimidazole]‐propyl‐sulfonic acid). The stability of the complexes in presence of ascorbic acid was examined by UV/Vis and 13C NMR. To recognize if His15 side‐chain is the metalation site of HEWL, the interactions between the complexes and imidazole, as a simple model of histidine, were investigated by 1H and 13C NMR. The DNA binding studies of the complexes were reported. For this class of Au(III) complexes, it is preferred to decorate the pyridylbenzimidazole system with ethyl group rather than sulfonate and phthalimido group to have a complex with interesting antifungal activity against Candida albicans and Cryptococcus neoformans var. grubii. Au(III) complex, having sulfonate group, is noncytotoxic to non‐malignant cells (human embryonic kidney cells (HEK293)), shows negligible hemoglobin release and is safe to the normal cells if applicable. [ABSTRACT FROM AUTHOR]

Reaction of N‐(2‐pyridylmethylene)benzene‐1,4‐diamine (L) with [MBr(CO)5] (M = MnI and ReI) affords complexes of the type [MBr(CO)3L] [M = MnI (1) and ReI (2)]. Complex 1 releases CO upon illumination with light in the range of 525–468 nm. No photo induced CO release is detected from 2. Reactive azide complex 3, obtained by bromide's ligand exchange, reacts with the electron‐poor alkyne dimethyl acetylene dicarboxylate giving triazolato complex 4 ([Mn(triazolateCOOMe,COOMe)(CO)3L]) via the free catalyst [3+2] cycloaddition coupling. Complex 1 exhibits interesting antifungal activity (MIC = 30 nM) against Candida albicans and Cryptococcus neoformans as well as cytotoxic activity of 12.56 µg/mL against noncancerous human embryonic kidney cells. Reactivity of the complexes towards hen egg white lysozyme is studied by electrospray ionization mass spectrometry. Are manganese(I) photoCORMs stable in presence of biomolecules? Hen white egg lysozyme has been used as a model in this study. The antimicrobial activity and cytotoxicity of the studied green‐light induced PhotoCORM were evaluated and compared with the inactive CO‐releasing ReI analogue. [ABSTRACT FROM AUTHOR]

Mono- and binuclear blue-light-induced CO-releasing molecules based on a fac-MnBr(CO)3 moiety and bearing benzimidazole ligands furnished with either a sulfonate or phosphonium group were synthesized. The effect of the ancillary ligand (Br− and NCS−) on the CO releasing properties was studied and compared with that of the triazolate complex synthesized by the free catalyst [3+2] cycloaddition iClick reaction. An extension of the iClick reaction to the binuclear complex was successful. The assignment of electronic transitions was done by TDDFT. The photoprocess of the binuclear complexes was faster than that of the mononuclear complex. [ABSTRACT FROM AUTHOR]

The lysozyme- and DNA-binding affinities of the biologically active cisplatin analogues, Pd(II) (1) and Pt(II) (2) complexes of functionalized N,N-pyridylbenzimidazole ligand, are reported. The electronic transitions were studied by time-dependent density functional theory. Complex 1 exhibits interesting antifungal activity against Candida albicans (MIC = 32 μg mL−1; 64 nM) and Cryptococcus neoformans (MIC = 16 μg mL−1, 32 nM). Complex 1 is covalently bound to DNA and lysozyme via the elimination of the chloride ligand(s). When complex 2 interacts with lysozyme, two adduct peaks are observed in the mass spectrum corresponding to binding of Pt(II) ion to lysozyme. [ABSTRACT FROM AUTHOR]

Reaction of 4′-(2-pyridyl)-2,2′:6′,2″-terpyridine (L PY ) and 4′-(4-phenylmorpholine)-2,2′:6′,2″-terpyridine (L morph ) with {[RuCl 2 (CO) 3 ]} 2 in methanol affords [RuCl 2 (L PY -κ 2 N 1 N 2 )(CO) 2 ] ( 1 ) and a mixture of [RuCl 2 (L moph -κ 2 N 1 N 2 )(CO) 2 ]/[RuCl 2 (L morph -κ 3 N 1 N 2 N 3 )(CO)] ( 2 ), respectively. Their photoactivatable CO releasing properties are investigated upon the exposure to light source at 365 nm. One CO molecule is released from 1 at the excitation wavelength 365 nm, while the ligand changes its bidentate mode into the meridional tridentate one. The illumination profile and the influence of the uncoordinated pyridine arm on CO release are examined by solution 1 H and 13 C NMR spectroscopy. The electronic transitions are studied by TDDFT. The DNA and hen white egg lysozyme binding affinity of the complexes are studied by UV/Vis. and electrospray ionization mass spectrometry. Stable lysozyme complexes, capable of photo induce CO, are formed via the loss of the labile chloride ligands or terpyridine moiety. [ABSTRACT FROM AUTHOR]

Pd(ii) and Pt(ii) compounds bearing N,N-pyridylbenzimidazole derivatives with an alkylated sulfonate or phosphonium side chain are able to bind the model protein lysozyme both covalently and non-covalently as an entire compound or as a product of a hydrolysis reaction. The interactions with the protein and the origin of the different behaviors of these complexes were unknown hitherto. Here, we present four crystal structures of their adducts with lysozyme. Pt- and Pd-containing fragments bind the protein with different stoichiometries close to the side chains of His15, Asp87, Asp101 and Asn77. The compounds bearing a phosphonium side chain degrade during the reaction with lysozyme. Data show the origin of the non-covalent mode of binding of Pd and Pt compounds bearing a sulfonate side chain, which drives the recognition process by forming a series of H-bonds and coulombic interactions with positively charged residue side chains. In a separate experiment, the structure of the adduct that is formed when the Pd(ii) compound containing an alkylated sulfonate group reacts with ribonuclease A was also determined. In this structure, the sulfonate-Pd(ii) complex binds the side chain of His105 on the surface of the protein and the side chain of the catalytically important His119 residue. Altogether, our data provide a structural basis for understanding the behavior of the analyzed Pd(ii)- and Pt(ii)-based cisplatin analogues in their reactions with proteins and show the first structural characterization of an adduct comprising a cisplatin analogue that is non-covalently bound to a protein. The results suggest that functionalization of a ligand system with a sulfonate group can significantly alter the protein-binding activity and thus the overall pharmacological profile of Pd(ii)- and Pt(ii)-based drugs. [ABSTRACT FROM AUTHOR]

The synthesis of visible-light induced carbon monoxide releasing complexes (photoCORMs) with some perquisites such as solubility in water or in a medium suitable for drug delivery (H 2 O/DMSO), dark stability under the aerated conditions and CO releasing upon the illumination, is the major challenge for the phototherapeutic CO applications. The reaction of N-(2-thiazolyl)-1H-benzotriazole-1-carbothioamide (HL) with [MnBr(CO) 5 ] affords fac -[MnBr(CO) 3 (HL)] (CORM-NS1). The aerated DMSO solution of CORM-NS1 is stable for 16 h. The process of the photo induced CO release is studied using two excitation wavelengths, 468 and 525 nm and quantitatively estimated by the myoglobin assay and commercial gas sensor. The electronic structure of CORM-NS1 is calculated at PCM/TD-B3LYP/def2-SVP (or LANL2DZ) level of theory. Interaction of CORM-NS1 with hen egg white lysozyme (HEWL), as a biocompatible carrier, is studied in the dark and upon illumination by means of ESI-MS. In the dark, an adduct peak corresponding to binding of Mn(CO) 3 fragment to HEWL is observed, which disappears upon the illumination with either the green or blue light. [ABSTRACT FROM AUTHOR]

• Selective colorimetric recognition of cyanide ion in both solution and solid states. • Fast response to CN– (< 5 s). • Water percentage has a key role in the cyanide's recognition mechanism. • Recognition mechanism was investigated by IR soectroscopy. A novel chemosensor based on Nifuroxazide Cr(III) complex was developed for recognizing CN– over other tested anions e.g., F–, Cl–, Br–, I–, CH 3 COO–, NO 2 –, PO 4 3–, and SCN– in DMSO–H 2 O (9:1, v/v) and THF. Without any interference from the tested anions, UV–vis spectroscopy was used to investigate the recognition of CN–. The deprotonated species that resulted from the ionization of the phenolic group may be the cause of the color shift that occurred after adding CN– to the solution of the Cr(III) complex. The charge transfer interaction between the electron-donor unit and the electron-deficient nitro-furan moiety was improved as a result of the ionization of the phenolic group. The fact that the developed color vanishes in protic polar solvents e.g., H 2 O, CH 3 OH, and C 2 H 5 OH may lend credence to this assumption. The Lambert–Beer's law was obeyed in the concentration ranges of 3.4 × 10−3–3.4 × 10−5 M and 1.0 × 10−4–5.0 × 10−6 M in DMSO–H 2 O (9:1, v/v) and THF, respectively, reflecting the significant role of the solvent in controlling the sensitivity of the developed probe. The electronic transitions were investigated by executing time-dependent density functional theory calculations. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • DMSO and metal ion have roles in regulating the triazolate isomers ratio of the iClick reaction. • A non-equivalent mixture of N1 and N2 triazolate isomers in the case of symmetrical alkyne. • The nature of the alkyne affects the ratio of the formed triazolate Pd(II) isomers. At the ambient temperature and under catalyst-free conditions, reactions between [MN 3 (LET)]PF 6 (M = Pd(II) and Pt(II); LET = 2,6-bis(1-ethylbenzimidazol-2′-yl)pyridine) and substituted alkynes (dimethyl acetylene-dicarboxylate and 4,4,4-trifluoro-2‑butynoic acid ethyl ester) afforded the corresponding triazolate complexes. These reactions produced a mixture of triazolate bound isomers. The N1 triazolate isomer of the Pt(II) complexes, which first appeared in the [3 + 2] coupling, eventually isomerized to the N2-analogue during the incubation in DMSO. The reactions of [MN 3 (LET)]PF 6 with asymmetric alkyne, 4,4,4-trifluoro-2‑butynoic acid ethyl ester, produced a mixture of the three anticipated triazolate isomers, according to 19F NMR spectroscopy. The stability of the triazolate complexes was investigated, along with the cycloaddition reaction's mechanism and the nature of the intermediates, using NMR spectroscopy. [ABSTRACT FROM AUTHOR]

New cisplatin analogue Pd(ii) and Pt(ii) complexes bearing charged pyridylbenzimidazole derivatives furnished with either an alkylated sulfonate or a phosphonium side chain were synthesized, fully characterized and tested for their antimicrobial and cytotoxic activities against noncancerous human embryonic kidney cells (HEK293). The interactions with CT-DNA were investigated using UV/vis spectroscopy. Assignment of the electronic transitions was performed with the aid of TDDFT. The complexes showed interesting antifungal activity against Candida albicans and Cryptococcus neoformans. The Pd(ii) complex conjugated with alkylated triphenylphosphonium exhibited higher cytotoxicity (CC50 = 8.932 μg mL−1, equivalent to 12 nM) than the others. The reactivity towards hen egg white lysozyme (HEWL) was investigated by electrospray ionization mass spectrometry. The formation of DNA- and HEWL-adducts was achieved via the noncovalent and covalent interactions. [ABSTRACT FROM AUTHOR]

Background: Multiple studies have quantified the relationship between aortic size and risk of dissection. However, these studies estimated the risk of dissection without accounting for any increase in aortic size from the dissection process itself. Objectives: This study aims to compare aortic size before and after dissection and to evaluate the change in size consequent to the dissection itself. Methods: Fifty-five consecutive patients (29 type A; 26 type B) with aortic dissection and incidental imaging studies prior to dissection were identified and compared to a control group of aneurysm patients (n = 205). The average time between measurement at and prior to dissection was 1.7 ± 1.9 years (1.9 ± 2.0 years mean inter-image time in the control group). A multivariate regression model controlling for growth rate, age, and gender was created to estimate the effect of dissection itself on aortic size. Results: The mean aortic sizes at and prior to dissection were 54.2 ± 7.0 and 45.1 ± 5.7 mm for the ascending aorta, and 47.1 ± 13.8 and 39.5 ± 13.1 mm for the descending aorta, respectively. The multivariable analysis revealed a significant impact of the dissection itself (p < 0.001) and estimated an increase in size of 7.65 mm (ascending aorta) and 6.38 mm (descending aorta). Thus, a proportional estimate of 82.8% (ascending aorta) and 80.8% (descending aorta) of dissections are made at a size lower than the guideline-recommended threshold (55 mm). Conclusions: The aortic diameter increases substantially due to aortic dissection itself and, thus, aortas are being dissected at clinically meaningfully smaller sizes than natural history analyses have previously suggested. These findings have important implications regarding the size at which the risk of dissection is increased. [ABSTRACT FROM AUTHOR]

The photoinduced carbon monoxide releasing properties of pyridylbenzimidazole-based RuII-carbonyl complexes functionalized with alkylated sulfonate (LSO3H), phthalimide (LPhth), and morpholine (Lmorph) moieties, [RuCl(CO)3LSO3H]Cl (1) and [RuCl2(CO)2L] {where L = LPhth (2) and Lmorph (3)}, are reported. The geometrical stereochemistry and electronic transitions are assigned with the aid of DFT and TDDFT calculations. The compounds are evaluated for potential antimicrobial and cytotoxic active properties [against noncancerous human embryonic kidney cells (HEK293)]. Complex 2 shows interesting antifungal activity towards Candida albicans and Cryptococcus neoformans, with a similar MIC value of 24 nM. Metalation of hen egg-white lysozyme (HEWL), as a biocompatible carrier, is studied in the dark and upon exposure to light. Stable protein adducts, capable of release CO upon illumination, are formed. [ABSTRACT FROM AUTHOR]

In the present work, experimental and theoretical structural studies of two new nitazoxanide (NTZ) complexes, [Co(NTZ)(NO3)2(OH2)] (1) and [Ni(NTZ)(CH3COO)(OH2)]·CH3COO (2) were reported. The susceptibility of Staphylococcus aureus and Escherichia coli towards NTZ and its complexes was assessed. NTZ behaves as a monodentate ligand via the thiazole N atom forming distorted octahedral and tetrahedral complexes with Co(II) and Ni(II) ions, respectively. The d‐d transitions were assigned by the aid of time‐dependent density functional theory calculations. The magnetic susceptibility value of 1 remains unchanged in the temperature range of 298–77K, while that of 2 decreases linearly with the temperature to attain 2.79 μB at 77K. Coordination of NTZ (0.084 μmol ml−1) to Co(II) (1) (0.028 μmol ml−1) and Ni(II) ions (2) (0.079 μmol ml−1) leads to an improvement in the toxicity against S. aureus. [ABSTRACT FROM AUTHOR]

[MCl(H2L)(OH2)]·1.5H2O (M = Pd(II) ( 1) and Pt(II) ( 2)) and [Ru(H2L)2(OH2)2]·3H2O ( 3) (H3L: N-phenyl, N`-(3-triazolyl)thiourea) were synthesized, characterized and tested for their antibacterial activities against Staphylococcus aureus and Escherichia coli bacteria. The thiourea derivative is coordinated to Mn+ ions as a mono-negatively N,S-bidentate ligand via the enolization of C = S group and triazole N center. The density functional theory calculations reveal that presence of a water molecule in a trans position to triazole ring increased the stability of d8 metal ions complexes via the formation of strong Cl...NH intramolecular H-bond. The cis-Ru(II)-isomer with two isoenergetically H2L− molecules are more stable than the trans-analog. Coordination of H3L to Ru(II) ion did not alter the toxicity of the free ligand, while the interaction with the d8 metal ions gave rise to inactive compounds. [ABSTRACT FROM AUTHOR]

Objective: To compare recovery outcomes between laparoscopic donor nephrectomy (LDN) and open donor nephrectomy within a specified enhanced recovery program (ERP) for left kidney donations.Patients and Methods: A phase III randomized trial was conducted between January 2013 and June 2015; eligible left-side donors were randomized to laparoscopic or open donor nephrectomy in a 1:1 ratio with recovery optimized within a standardized ERP. The primary outcome was patient-reported measure of physical fatigue, as measured by the physical fatigue domain of the translated Multidimensional Fatigue Inventory 20. Secondary outcomes included other donor recovery outcomes, postoperative pain scores, hospital stay, perioperative complications, and graft outcomes.Results: A total of 224 donors (laparoscopy, n = 113; open surgery, n = 111) were randomly allocated. Six weeks postoperatively, physical fatigue domain scores in Multidimensional Fatigue Inventory 20 were significantly lower in the LDN group (mean: laparoscopy, 8.2 ± 3.2 vs open surgery, 13.05 ± 2.9) (P = .007). Median total hospital stay was also significantly shorter in the LDN group (median: laparoscopy, 2; interquartile range, 1-5 vs open surgery, 4; interquartile range, 2-9 days) (P = .002). LDN was associated with less pain scores and less non-opioid analgesic requirements. Warm ischemia times were not significantly different in both groups (mean: laparoscopy, 2.5 ± 0.8 vs open surgery, 2.2 ± 0.6) (P = .431).Conclusion: Even when optimized within an ERP, LDN was associated with less general and physical fatigue and better physical function at 6 weeks postoperatively when compared with open surgery for left kidney donations. [ABSTRACT FROM AUTHOR]

The photoinduced CO-releasing properties of [RuLPy(CO)2Cl2] (1), [Ru(LPy2Bz-ĸ²N¹,N²)(CO)2Cl2] (2), and [Ru(LPy2Bz-Et-ĸ³N¹,N²,N³)(CO)2(Cl)]·PF6 (3) [LPy = 2-(2-pyridyl)-benzimidazole, LPy2Bz = 2,6-bis(benzimidazole-2'-yl)pyridine, and LPy2Bz-Et = 2,6-bis(1-ethyl-benzimidazol-2'-yl)pyridine] in both DMSO and reduced myoglobin solution are reported. Complexes 1 and 2 release CO upon illumination at 365 nm. The bidentate chelation mode of LPy2Bz in 2 is changed into a meridional tridentate mode upon the ethylation of the benzimidazolic NH groups, 3. The extension of the conjugation system and the shift of the MLCT band into the visible region in 3 give rise to the RuII dicarbonyl complex capable of releasing CO at 468 nm. During illumination of 2, the chelation mode of LPy2Bz is changed from ĸ²N¹,N² to ĸ³N¹,N²,N³, as monitored by solution NMR spectroscopic studies. The spectral properties were studied by TD-DFT calculations. The interaction of 1-3 with hen-egg-white lysozyme, as a biocompatible carrier, has been studied by ESI-MS and UV/Vis spectroscopy in the dark and upon illumination. Stable protein adducts containing the RuII(CO)2 moiety, capable of photoinduced release of CO, are formed. [ABSTRACT FROM AUTHOR]

A new class of blue-light triggered carbon monoxide releasing molecules based on Mn(CO) 3 Br(N,S) ((N,S) = N,S-bidentate thiourea ligands) has been reported in this work. The 1 H and 13 C NMR analysis indicated that the thioureas coordinate to Mn(I) in the thione form. The stability test and the ability to derive CO to DMSO and myoglobin solution upon the exposure to 468 nm light source have been investigated. The benzothiazole-thiourea-CORM released only one CO equivalent, while the pyridine-analogs offered two molecules at the same experimental conditions. Natural bond orbital analysis has been carried out to give details about the hybridization of Mn C and C O bonds, natural charge, electronic arrangement of metal ion and strength of interaction between Mn(I) and the coordination sites. Both functional, B3LYP and CAM-B3LYP compare well with the experimental findings, where the longest wavelength band is assigned to MLCT. [ABSTRACT FROM AUTHOR]

The reaction of bromazepam (7-bromo-1,3-dihydro-5-(2-pyridyl)-2 H-1,4-benzodiazepin-2-one, BZM) with Cr(III) ( 1), Fe(III) ( 2) and Ru(III) ( 3) salts gives complexes of the type [M(BZM)3]⋅3X (X = Cl or NO3). Structural characterization was extensively carried out using various analytical and spectral tools such as infrared, 1H NMR and UV-visible spectroscopies and magnetic, conductance, elemental and thermal analyses. BZM is a bidentate ligand and interacts with the metal ions via the pyridine and benzodiazepin-2-one nitrogen atoms. The magnetic and electronic properties of 2 and 3 are consistent with low-spin octahedral complexes. The three BZM molecules are non-isoenergetically coordinated to the metal ions and this is reflected in the values of the second-order interaction energy. The antibacterial activity was studied using Staphylococcus aureus and Escherichia coli. Coordination of BZM to Cr(III) or Ru(III) ions leads to a marked increase in toxicity with respect to the inactive Fe(III) complex 2. [ABSTRACT FROM AUTHOR]

OBJECTIVES: The objective of this study is to retrospectively analyse surgical outcomes in patients aged 75–79, and 80 and above.METHODS: Between 2000 and 2015, 108 patients aged 75–79 (G75, mean age 76.9 ± 1.5years) and 72 patients aged 80 and above (G80, mean age 82.2 ± 2.1years) underwent elective aneurysm repair. Operative outcome and survival was compared with 727 contemporary younger counterparts aged <75 years (GCtrl, mean age 56.6 ± 11.7years).RESULTS: Postoperatively, patients with advanced age showed a higher incidence of prolonged ventilation (G80 21.4%, G75 8.4%, GCtrl 2.9%; P < 0.001), low cardiac output syndrome (G80 11.4%, G75 1.9%, GCtrl 2.2%; P = 0.001), multi organ failure (G80 2.9%, G75 0%, GCtrl 0.1%; P = 0.022), haemofiltration (G80 8.6%, G75 0.9%, GCtrl 0.6%; P < 0.001), and infection (G80 10.0%, G75 6.5%, GCtrl 3.5%; P = 0.017). Operative mortality was significantly increased in the elderly (G80 11.1%, G75 3.7%, GCtrl 1.4%; P < 0.001). Mid-term survival differed significantly between the surgical groups. Multivariate regression analysis precluded age as an independent predictor of operative mortality. CONCLUSIONS: Elderly patients showed a higher operative risk compared to their younger counterparts. However, age per se is no suitable indicator of surgical risk and well-selected patients with large threatening aneurysms may benefit from intervention. [ABSTRACT FROM AUTHOR]

The reaction between [Mn(CO) 5 Br] and antibacterial drugs (Nifuroxazide (NIF) and Nitazoxanide (NTZ)) afforded fac -[MnBr(CO) 3 (NIF)] ( 1 ) and fac -[MnBr(CO) 3 (NTZ) 2 ] ( 2 ) complexes, which were characterized by different analytical and spectral tools. The photo-induced CO releasing properties and the ability of the metal carbonyls to drive CO to the myoglobin solution were investigated. The green-light (525 nm) illumination of the DMSO solution of 1 for 20 min gave rise to the maximum amount of CO. Compared with the DMSO solution of 1 , the rate of CO release from the 80% aqueous-DMSO mixed media is slower, and the plateau is reached upon the illumination for 140 min. On the contrast, a clear isosbestic point is developed during the storing of the DMSO solution of 2 for 6 h, which reflects its instability. To drive CO from 2 to myoglobin solution, the energy of the green light was not sufficient. However, the grown of the bands corresponding to the formation of carboxy-myoglobin species is stopped after 50 min of the irradiation at 468 nm and 36 min at 410 nm. The electronic structures and the related electronic transitions have been calculated by TD-DFT/B3LYP (or CAM-B3LYP)/LANL2DZ methods. The spectra calculated by the hybrid exchange-correlation functional CAM-B3LYP with a long range correction term are more closed to the experimental findings. The remarkable toxicity of 2 against the tested microbes, with respect to the free drug, may be attributed to the change of the lipophilicity of free NTZ upon the complex formation as well as the releasing of CO upon the incubation in dark. [ABSTRACT FROM AUTHOR]

Two new photoactivatable carbon monoxide-releasing molecules (CORMs), fac-[Mn(CO)3(BZM)Br] ( 1) and [RuCl2(BZM)(CO)2] ( 2), derived from the anti-anxiety drug bromazepam (BZM) and capable of rapid release of CO upon the illumination with light-emitting diode (LED) source light (470-525 nm) have been synthesized and characterized. The photo-delivery of CO to myoglobin solution could be achieved via the illumination of 1 at 525 nm for 10 min or at 470 nm for 1 min. The addition of water to a dimethylsulfoxide (DMSO) solution of 1 increases its stability, but it decreases the rate of the CO-releasing process. CORM 2 behaves as a good visible photoCORM, whereby its two CO molecules are released within 10 min upon exposure to LED light source at 470 nm in DMSO. The illumination profile of 2 was also examined using solution . The cis/ trans stereochemistry around the Ru(II) ion was determined using quantum chemical calculations. The formation of photoCORMs leads to an improvement in the toxicity of BZM against tested microbes. [ABSTRACT FROM AUTHOR]

[M(NTZ)Cl 2 ] (M = Pd(II) ( 1 ), Pt(II) ( 2 ) and NTZ = Nitazoxanide) and [Ru(NTZ)Cl 3 (OH 2 )] ( 3 ) complexes have been synthesized and characterized by elemental analysis, thermogravimetric analysis, IR, 1H NMR, conductance and magnetic measurements. NTZ is coordinated to the metal ions as a bidentate ligand via the N - atom of the thiazole ring and amide C O. The susceptibility of Staphylococcus aureus and Escherichia coli towards NTZ and its complexes has been evaluated. The calculated electronic structures and the related electronic transitions have been obtained at TD-DFT/B3LYP/LANL2DZ level of theory. Upon the chelation, the value of the natural charge of Ru(III) ion (+0.182e) was found to be lower than those of Pd(II) and Pt(II) ions (∼+0.398e) in their complexes, which reflects the higher complexation ability of NTZ towards the high oxidation state and low-d-orbital population metal ion. Complex 3 is existing in a low-spin octahedral arrangement. The DC magnetic measurements in terms of Weiss constant revealed the presence of the intermolecular interactions among the spin carriers. The low stability of 1 – 3 in DMSO and the rate of the releasing of NTZ was the factor which reproduces the order of the toxicity (NTZ > 2 > 3 > 1 ) against the tested microbes. [ABSTRACT FROM AUTHOR]

[MnBr(CO) 3 (TZ)] ( 1 ) and [Mn(CO) 3 (MZ)] ( 2 ) (TZ = Tazarotene and MZ = Metamizole) have been synthesized and characterized as new visible light photo-trigged carbon monoxide releasing molecules. The ability to deliver CO to DMSO or myoglobin solution has been studied. TZ behaves as a bidentate ligand via the pyridine N-atom and π–C C group, while MZ is a mono-negatively tridentate ligand and coordinates to Mn(I) through the pyrazolone C O, –SO 3 − and tertiary amino groups. These photoCORMs cannot be stored for a long time in DMSO, but they are able to release CO fast upon the exposure to the light (412–468 nm). About one CO equivalent was delivered from CORM 1 to the myoglobin solution upon the exposure to 468 nm LED lamp for 42 min. The electronic configuration of the metal center, hybridization type and nature of bonding have been obtained by natural bond orbital analysis. TD-DFT calculations have been performed to recognize the electronic structure and to explain the related experimental findings. The CORMs have been screened for their antibacterial activity against Staphylococcus aureus and Escherichia coli in comparison to their parent drugs. [ABSTRACT FROM AUTHOR]

We review current knowledge regarding the natural transition of aortic dissection from acute to chronic stages. As this is not well understood, we also bring to bear new data from our institution. Type A dissection rarely transitions naturally into the chronic state; consequently, information is limited. Type B dissections are routinely treated medically and indeed undergo substantial changes during their temporal course. General patterns include: 1) the aorta dilates and, absent surgical intervention, aortic enlargement may cause mortality; 2) continued false lumen patency, particularly with an only partially thrombosed false lumen, increases aortic growth, whereas calcium-channel blockers affect aortic dilation favorably; 3) aortic dilation manifests a temporal dynamic, with early rapid growth and deceleration during transition; 4) the intimal flap dynamically changes over time via thickening, straightening, and loss of mobility; and 5) temporal remodeling, on the cellular level, initially shows a high grade of wall destruction; subsequently, significant fibrosis ensues. [ABSTRACT FROM AUTHOR]

Novel copper(II) complexes of an anti-parasitic Flubendazole drug (FLU), [Cu(FLU) 2 X 2 ]·zH 2 O (X = Cl − ( 1 ), C 2 H 3 O 2 − ( 3 ), and ClO 4 − ( 4 ), z = 1–4) and [Cu(NO 3 )(FLU) 2 (OH 2 )]∙NO 3 ∙2H 2 O ( 2 ) were synthesized and characterized using elemental analysis, TG, IR, EPR, magnetic and conductance measurements. Geometry optimization and natural bond orbital analysis were performed at DFT/B3LYP/6-31G * level of theory. Electronic transitions were calculated by TD-DFT. Tenorite (CuO) nanoparticles with promising catalytic properties were prepared in air via the controlled thermal decomposition of 1–4 . The polymorph and morphology of the prepared nano-tenorite particles were investigated by powder XRD and field emission scanning electron microscope. The catalytic degradation of methylene-blue (MB) dye exposed to the UV radiation in presence of CuO nanoparticles as a catalyst was studied at room temperature in water. [ABSTRACT FROM AUTHOR]

Introduction of tetrazolate moiety in the coordination sphere of Pd(II) complex, functionalized with tridentate benzimidazole ligand, via the catalyst [3+2] cycloaddition reaction, gave rise to potential antibacterial properties. [Display omitted] Two [PdN 3 L]PF 6 complexes (L = 2,6-bis(1-ethyl-benzimidazol-2́-yl)pyridine (LBZ) and 4-(2-pyridyl)-2,2′:6′,2′'-terpyridine (LPY)) underwent catalyst-free 1,3-dipolar cycloaddition coupling with phenyl isothiocyanate at the room temperature giving the corresponding tetrazole–thiolato complexes. 1H NMR studies showed that the N1-isomer appeared first in the catalyst-free coupling, then gradually isomerized to the more stable tetrazole–thiolato isomer. The interconversion of N1-isomer into the S-isomer is accompanied by a decrease of the greater steric demand of the 5-membered ring. Tetrazolate complex of LBZ displayed higher antifungal activity (MIC ≤ 0.25 μg/mL) than the chloride analogue (MIC = 0.5–1.0 μg/mL) and the reference drug, Fluconazole (MIC = 0.125–8.0 μg/mL) against Candida albicans and Cryptococcus neoformans. The treated non-cancerous human embryonic kidney cells (HEK293) showed no cytotoxicity and no haemolysis release at the measured concentrations of the chloride complex of LBZ and tetrazolate complex of LPY. [ABSTRACT FROM AUTHOR]

[Co(FBZ) 2 (H 2 O)]·2NO 3 ·0.5H 2 O ( 1 ), [Ni(FBZ) 2 X 2 ]·zH 2 O (X = Cl ​− , z = 0.5 ( 2 ) and X = CH 3 COO − , z = 1 ( 3 )) and [Cu(FBZ) 2 (H 2 O) (NO 3 )]·NO 3 ·1.5H 2 O ( 4 ) (FBZ = methyl-5-(Phenylthio) benzimidazole-2-carbamate; Fenbendazole) complexes were synthesized and characterized by elemental analysis, thermal, IR, EPR, UV–Vis, magnetic and conductance measurements. Geometry optimization, molecular electrostatic potential maps and natural bond orbital analysis were carried out at DFT/B3LYP/6-31G ∗ level of theory. FBZ behaves as a neutral bidentate ligand via the pyridine-type nitrogen of the benzimidazole moiety and the carbamate group. Three-step ionization with pK a values of 3.38, 4.06 and 10.07 were reported for FBZ. The coordination of FBZ to the metal ions led to an increase in the antibacterial activity against the tested Staphylococcus aureus and Escherichia coli bacteria. [ABSTRACT FROM AUTHOR]

Three novel poly vinyl chloride (PVC) ( A), carbon paste (CP) ( B), and coated glassy carbon-MWCNT (CGC) ( C) salicylate (sal−) sensors based on new synthesized [Co(L2Cl)Cl3(H2O)] ⋅ H2O complex (L2Cl=(1H-benzimidazol-2-ylmethyl)-N-(2-chloro-phenyl)- amine)), o-nitrophenyloctyl ether as a mediator and tridodecylmethylammonium chloride as a cationic additive were successfully used for determination of sal− in human plasma and pharmaceutical formulations. The sal−-sensors exhibited enhanced sensitivity with slope of −63.5, −60.5 and −58.9 mV/decade and detection limit of 1.0×10−5, 4.0×10−7, and 1.0×10−6 mol L−1 for A- C sensors respectively. Quantum chemical calculations were carried out by HF and DFT/B3LYP methods to explore and investigate the interaction between the receptor and the different anions. The intermolecular H-bond created between the uncoordinated CO of salicylate group and the secondary amino group in the complex is the key factor of the selectivity of the proposed sensor. A linear relation is established between the natural charge on the Co center and the value of the binding energy, where the decrease in positive charge is associated by an increase in the anion binding energy. [ABSTRACT FROM AUTHOR]

New mononuclear copper(II) complexes of the first topical receptor-selective retinoid drug, Tazarotene (Tz), of the type [Cu(Tz) 2 X 2 ] (X = Cl ( 1 ) and Br ( 2a )) were synthesized, characterized (elemental analysis, TG, FT IR, UV–Vis, EPR, magnetic susceptibility, molar conductance measurements and single crystal X-ray analysis) and tested for their antimicrobial activities against Staphylococcus aureus and Escherichia coli . Tazarotene behaves as a neutral monodentate ligand via the pyridine nitrogen atom. Complex 1 crystallizes in the monoclinic P 2 1 / c space group. The environment around the metal center in 1 could be described as an intermediate between tetrahedral and square–planar geometries. Crystals of the polymeric {[Cu(Tz)(μ-Br)]} n ( 2b ) complex were obtained by the slow evaporation of the reaction filtrate of complex 2a . The distorted tetrahedral environment around Cu(I) is formed from the pyridine N atom of Tz, the S atom of another Tz molecule as well as two bridged bromine atoms, with a Cu…Cu′ distance of 3.327 Å. Time-dependent density functional theory calculations were carried out to understand the electronic structure and to explain the related experimental findings. The electronic arrangement, type of hybridization and nature of bonding were obtained from natural bond orbital analysis. [ABSTRACT FROM AUTHOR]

[M(HL)2] complexes (M = Co(II) (1), Ni(II) (2), and Cu(II) (3); H2L = 4-hydroxybenzoic[(5-nitro-2-furanyl)methylene]hydrazide acid, nifuroxazide) were synthesized, characterized (by elemental analysis, TG, IR, UV–vis., EPR, magnetic, and conductance measurements) and tested for their antimicrobial activities. H2L is a mono-negative bidentate ligand via hydrazone N and C–O−forming intermediate complexes between tetrahedral and square-planar geometries (“flattened” tetrahedron,D2dsymmetry) for1and2, as well as square-planar for Cu(II) complex3. Natural bond orbital analysis revealed that the interaction of oxygen with metal ion is the main factor which determines the stability of1–3as the binding energy decreases with an increase in the M–O bond length. Time-dependent density functional theory calculations were carried out to understand the electronic transitions in related experimental observations. The reduction potential values of the nitro group are affected by the metal center. Ni(II) complex2displayed the highest activity among the tested complexes againstEscherichia coliwith a MIC50value of 0.098 μmol mL−1compared with 0.131 (1) and 0.117 μmol mL−1(3). [ABSTRACT FROM PUBLISHER]

New cis-platin analogs Pd II and Pt II complexes of (1H-benzimidazol-2-ylmethyl)-N-(4-chloro-phenyl)-amine (L Cl ) and (1H-benzimidazol-2-ylmethyl)-N-(4-iodo-phenyl)-amine (L I ) were prepared as potential antitumor compounds, characterized (elemental analysis, TG/DTA, FT IR, 1 H NMR, MS, UV–Vis. and conductance measurements) and tested for their cytotoxic activities against MCF7, HCT and HEPG2. The antibacterial activity was tested on against Staphylococcus aureus , Bacillus subtilis , Streptococcus faecalis , Escherichia coli , Pseudomonas aeruginosa and Neisseria gonorrhea . The effect of the aniline substituent on the toxicity was discussed. The experimental studies were complemented by quantum chemical calculations. TD-DFT calculations were carried out to understand the electronic structure and to explain the related experimental findings. Natural bond orbital analysis was performed to provide details about the electronic arrangement, type of hybridization and the nature of bonding. [ABSTRACT FROM AUTHOR]

Reaction of 5-Methyl-4-(2-nitro-phenylazo)-2-phenyl-2H-pyrazol-3-ylamine (H 2 L) with Co(II), Ni(II) and Cu(II) salts affords complexes of the type [M(HL) 2 ], which were characterized by elemental analysis, FT IR, UV–Vis, magnetic susceptibility, conductance measurements and single crystal X-ray diffraction. H 2 L crystallizes in a monoclinic space group C2/c, while the Cu(II) complex crystallizes in the triclinic P 1 ¯ (2) space group. H 2 L behaves as a mono-negatively bidentate ligand via N N and NH − . Comparison between the crystal and the optimized data at DFT/B3LYP/6-31G(d) level of theory was discussed. Time-dependent DFT calculations were performed to assign the electronic spectra. The natural charge of Ni II is more reduced than Co II and Cu II , which suggests the higher complexation ability of H 2 L toward the former ion. [ABSTRACT FROM AUTHOR]

A simple, sensitive and rapid method was developed for the quantitative analysis of sparfloxacin in its pharmaceutical formulations through the formation of charge transfer complexes with π-acceptor systems. The Lambert–Beer’s law was obeyed in the concentration ranges of 7–70 and 10–50 μg/mL sparfloxacin for 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and tetracyanoquinodimethane. Structural characterization of the isolated solid CT complexes was carried out by IR, 1 H NMR, UV–Vis. and MS. The experimental studies were complemented by quantum chemical calculations at DFT level of theory. The electronic structures were investigated by TD-DFT calculations. Natural bond orbital analysis and molecular electrostatic potential maps were helpful in assigning the CT route. The formation constant, molar extinction coefficient, oscillator strength, dipole moment, standard free energy and ionization potential were calculated. [ABSTRACT FROM AUTHOR]

[Display omitted] Carbon monoxide has recently emerged to promote tissue regeneration, enhance the innate immune system, and have anti-inflammatory and antibacterial properties. While the first generation Ru(II) carbonyl prodrugs (CORM-2 and CORM-3) displayed several beneficial biological effects, a search in the literature shows that little work has been done to address the drawbacks of CORM-2/-3, exploring other CO triggered methods for the next generation Ru(CO) 2 II based compounds and examining their valuable biological impact. We present a summary of most work related to Ru(II) carbon monoxide-releasing molecules, protein bioconjugation, and antibacterial and anti-inflammatory properties. [ABSTRACT FROM AUTHOR]