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Supplementary Table 1 from New Derivatives of Vitamin B12 Show Preferential Targeting of Tumors

Supplementary Table 2 from New Derivatives of Vitamin B12 Show Preferential Targeting of Tumors

We report the synthesis of novel rhenium and 99mTc ansa-arenophane complexes with bridging isoindolines. Inter-instead of intramolecular isoindoline formation leads to dinuclear macrocycles, one of which exhibits axial chirality.

Introducción: El uso de los hidrocarburos y sus derivados, han generado un problema de contaminación ambiental. Los estudios más actuales sugieren una solución a esta situación, basada en la degradación microbiológica o biotransformación, usando cultivos microbianos axénico. Objetivo: Desarrollar un mapeo sistemático de la literatura científica sobre las investigaciones, acerca de las bacterias y hongos en la biodegradación de Hidrocarburos. Metodología: Se realizó la exploración, clasificación, verificación y estudio de los documentos con las respectivas directrices de indagación en relación al propósito de esta investigación. Los documentos obtenidos de WoS y Scopus se fusionaron y se eliminaron las réplicas, para esto se utilizó el software R studio. Posteriormente, se desarrolló un estudio de origen, referente teórico, estudio bibliométrico y de redes sobre bacterias y hongos en la biodegradación de Hidrocarburos. Resultados: La búsqueda arrojó un total de 424 registros. Se logró evidenciar que la temática ha tenido un aumento significativo a través de los años, principalmente a partir del año 2015, teniendo un incremento del 51.9% y con una tasa de aumento anual del 10.41%. El país con mayor producción científica es China con 67 publicaciones. Según los documentos científicos revisados hasta el 2021, este es el primer estudio de revisión sistémico sobre BHBH, que ha utilizado la aplicación R studio para analizar la productividad bibliográfica en este tema. Conclusión: Algunos de las bacterias nativos que biodegradan hidrocarburos son Gordonia, Brevibacterium, Dietzia, Burkholderia, Pseudomonas aeruginosa. Para hongos son Aspergillus, Penicillium, Fusarium. Para levaduras son Candida, Yarrowia y Pichia.

Efficient and robust electrocatalysts are required for the oxygen evolution reaction (OER). Photosystem II-inspired synthetic transition metal complexes have shown promising OER activity in water-poor or mild conditions, yet challenges remain in the improvement of current density and performance stability for practical applications in alkaline electrolytes in contrast to solid-state oxide catalysts. Here, we report that a nickel pseudo-complex (bpy)zNiOxHy (bpy = 2,2'-bipyridine) catalyst, which bridges solid oxide and molecular catalysts, exhibits the highest OER activity among nickel-based catalysts with a turnover frequency of 1.1 s-1 at an overpotential of 0.30 volts, even outperforming iron-incorporated nickel (oxy)hydroxide under an identical nickel mass load. Benefiting from the strong coordination between bpy and nickel, this (bpy)zNiOxHy catalyst exhibits long-term stability in highly alkaline media at 1.0 mA cm-2 for over 200 h and at 20 mA cm-2 for over 60 h. Our findings indicate that dynamically coordinating a small amount of bpy in the catalyst layer efficiently sustains highly active nickel sites for water oxidation, demonstrating a general strategy for improving the activity of transition metal sites with active ligands beyond the incorporation of metal cations to form double-layered hydroxides.

Oxidation of [Re(NCCH

C28H44Cl2N6O5Co, triclinic, P 1 ‾ $P‾{1}$ (no. 2), a = 11.20(2) Å, b = 12.70(3) Å, c = 12.80(4) Å, α = 100.30(12)°, β = 103.18(9)°, γ = 106.77(6)°, V = 1638(8) Å3, Z = 2, R gt (F) = 0.0372, wR ref (F 2) = 0.0890, T = 100 K.

This work focuses on the synthesis, purification, and analytical characterization of novel multifunctional Au NPs radiolabeled with

This work presents a straightforward method for the preparation of an isoindoline bridged [M(arene)

Objetivo: El objetivo principal de esta investigación es obtener bacterias del género Pseudomona spp. con capacidad biodegradora de hidrocarburos en muestras de agua superficial de la Bahía de Cartagena de Indias. Material y Método: Diseño observacional, descriptivo, transversal y prospectivo. Se tomaron tres muestras de agua superficial de la Bahía de Cartagena de indias, se sembraron para preadaptacion y adaptación biológica de las bacterias en medio con sales minerales, ACPM 1% v/v y petróleo crudo 1% v/v, como única fuente de carbono y energía. Resultados: Las bacterias que crecieron en los medios con petróleo crudo fueron identificadas en 31 morfotipos de colonias bacterianas, de las cuales solo el 19,4% dio positivo para la presencia de Pseudomona spp., y el 80,6% restante, pertenecientes a otros grupos bacterianos. Discusión: Se evidenció un cambio de color en el agar nutritivo durante el procedimiento de aislamiento de las bacterias de la muestra 2 relacionado con la presencia de especies de Pseudomonas en especial P. aeruginosa. Conclusión: Se reporta la presencia del género de Pseudomona spp. con capacidad biodegradadora de petróleo en una de las muestras de agua recolectadas en la Bahía de Cartagena. Este estudio abre la posibilidad de futuros trabajos de bioprospección e identificación metabólica de las cepas aisladas.

A novel proof-of-concept is reported to modify the water solubility and potential biological effects of a bis(diphenylphosphino)alkylamine (PNP) ligand and the corresponding metal complex, by introducing an amine group on the outer periphery of the pendant ligand arm. Thus, a tertiary butoxycarbonyl protected N’-Boc-ethylenediamine-N,N-bis(diphenylphosphino) (N‘-Boc-PNP) ligand (1) was synthesized by reacting the protected ethylenediamine and chlorodiphenylphosphine in a 1 : 2 molar ratio. The corresponding fac-[Re(CO)3(N‘-Boc-PNP)Br] (1A) complex was then obtained by reacting N‘-Boc-PNP (1) with (Et4N)2fac-[Re(CO)3Br3] in equimolar amounts in DCM at 50 °C. De-protection of the N‘-Boc pendant amine group in 1A with TFA leads to fac-[Re(NH3+-PNP)(CO)3Br]·CF3COO− (1B) which is soluble in D2O (>0.05 M). Treating 1B with saturated aqueous NaHCO3 yields fac-[Re(NH2-PNP)(CO)3Br]·MeOH (1C) in near quantitative yield. Although both 1A and 1C are not soluble in D2O, addition of TFA easily generates 1B (31P NMR), confirming the formation of the protonated amine. Isolation of fac-[99Tc(CO)3(N-Boc-PNP)(Cl)] (1D) confirmed that the rhenium and technetium (99Tc) can be easily interchanged in this process. Reported are hence the unique rhenium series of compounds 1A, 1B and 1C and the corresponding technetium complex 1D, unequivocally characterized by single crystal XRD, as well as IR and 1H NMR spectroscopy. Preliminary antimicrobial evaluation indicates that ligand 1 and its respective rhenium complexes (1A–1C) were not active against selected fungi (Candida albicans and Cryptococcus neoformans) and bacteria (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Staphylococcus aureus). These types of ligands and complexes therefore present themselves as excellent radio models for further evaluation using 186Re, 188Re and 99mTc to potentially study the radiotoxicity of appropriately designed complexes.

Two bidentate PNP ligands N,N-bis(di-p-tolylphosphino)cyclohexylamine (Cy-pTolPNP) (1) and N,N-bis(di-p-tolylphosphino)cyclobutylamine (Cb-pTolPNP) (2) were synthesized and crystallized. Coordination to the fac-[MI(CO)3]+ core (M = Re, 99Tc) yielded fac-[Re(Cy-pTolPNP)(CO)3Br] (1A), fac-[99Tc(Cy-pTolPNP)(CO)3Cl] (1B), fac-[Re(Cb-pTolPNP)(CO)3Br] (2A) and fac-[99Tc(Cb-pTolPNP)(CO)3Cl] (2B) in relatively good yields (56 to 86 %): The structures of 1, 2, 1A and 1B were studied by single crystal X-ray crystallography. Preliminary mitochondrial/antimicrobial evaluation of the free ligand (N,N-bis(di-p-tolylphosphino)-cyclohexylamine) (1) and its respective fac-[Re(CO)3]+ (1A) complex indicates that neither the free ligand nor the complex was active against selected fungi Eremothecium ashbyii and Nadsonia fulvescens. In addition, all four compounds were found to have no activity against Gram-positive and Gram-negative bacterial species. These biological results are essential to the understanding of how these types of complexes behave and show they are perfectly stable in the evaluated bio-environments. In addition, the results indicate that these ligands and complexes may present themselves as excellent models for radiotoxicity studies using technetium-99m, but more specifically, rhenium Re-186 and Re-188.

The oxidation of [Re(η6-C10H8)2]+ with AgI in acetonitrile yields [Re(NCCH3)6]2+. This fully solvated ReII compound was characterized by spectroscopic methods and X-ray structure analyses. We show that [Re(NCCH3)6]2+ acts as a precursor complex for a variety of substitution reactions. Treatment with monodentate triphenylphosphine (PPh3) and bidentate 1,2-bis(diphenylphosphino)ethane (dppe) yields the complexes [trans-Re(PPh3)2(NCCH3)4]2+ and [trans-Re(dppe)2(NCCH3)2]+, respectively. [trans-Re(dppe)2(NCCH3)2]+ is oxidized under mild conditions by AgI to its ReII analogue [trans-Re(dppe)2(NCCH3)2]2+. Reactions of [Re(NCCH3)6]2+ with a halide mixture consisting of NaX and AgX (X = Cl, I) result in the formation of the corresponding ReIII complexes [trans-ReX2(NCCH3)4]+. [trans-ReBr2(NCCH3)4]+ can be obtained directly from [Re(η6-C10H8)2]+ by oxidation with FeBr3 in acetonitrile. The title compound is thus a convenient starting material for ReII and ReIII complexes by simple solvent exchange, which are otherwise difficult to access.

We present the synthesis of the first mixed-ring rhenium fulvene sandwich complex, [Re(η6-C5H4CH2)(η6-C6H6)]+, from the respective carbinol precursor [Re(η5-C5H4CH2OH)(η6-C6H6)]. The demanding prep...

We present systematic kinetic studies of the interaction of a rhenium-based photosensitizer with a cobalt(II) tetrapyridyl water reduction catalyst coadsorbed on ZrO2 by transient IR and visible sp...

Arene substitution reactions in [M(η

Bis-arene sandwich complexes are generally prepared by the Fischer-Hafner reaction, which conditions are incompatible with most O- and N- functional groups. We report a new way for the synthesis of sandwich type complexes [Re(I· 6 -arene) 2 ] + and [Re(I· 6 -arene)(benzene)] + from [Re(I· 6 -napht) 2 ] + and [Re(I· 6 -napht)(benzene)] + , with functionalized arenes and pharmaceuticals. N-methylpyrrolidine (NMP) facilitates the substitution of naphthalene with the incoming arene. A series of fully characterized rhenium sandwich complexes with simple arenes, such as aniline, as well as with active compounds like lidocaine and melatonin are presented. With these rhenium compounds in hand, the radioactive sandwich complexes [ 99m Tc(I· 6 -pharm) 2 ] + (pharm = pharmaceutical) can be unambiguously confirmed. The direct labelling of pharmaceuticals with 99m Tc through I· 6 -coordination to phenyl rings and the confirmation of the structures with the rhenium homologues opens a path into molecular theranostics.

A novel proof-of-concept is reported to modify the water solubility and potential biological effects of a bis(diphenylphosphino)alkylamine (PNP) ligand and the corresponding metal complex, by introducing an amine group on the outer periphery of the pendant ligand arm. Thus, a tertiary butoxycarbonyl protected

Bis-arene sandwich complexes are generally prepared by the Fischer-Hafner reaction, which conditions are incompatible with most O- and N- functional groups. We report a new way for the synthesis of sandwich type complexes [Re(η

The Nano-Crystallization method has been extensively tested for the growth of single crystals of cationic coordination compounds, which are soluble in water. All three studied, diverse metal complexes could be crystallized with the help of pipetting robots commonly used for the crystallization of proteins and the anion small molecule screen. It was furthermore possible to obtain for each positively charged complex several structures with different anions. In one case, together with literature data, a total of six salts with different anions could be assembled, which allowed an investigation of the influence of the counterions on the inter-cation metal-to-metal distance. The Nano-Crystallization method can be recommended for the single crystal growth of cationic coordination complexes, which are stable in water and have an aqueous solubility of at least 2 mM. This is the first publication dedicated solely to the single crystal growth of coordination complexes.

Ni/CoOx sites were supported on an around 2 nm-TiOx modified hematite photoanode for water oxidation. TiOx demonstrates insignificant hole accumulation and a catalytically inactive surface that serves as an ideal platform. We reveal that the NiOx favors the extraction of holes from the TiOx surface, which are efficiently transferred to active CoOx for water oxidation.

Ferrocenes are versatile ligand scaffolds, complexes of which have found numerous applications in catalysis. Structurally similar but of higher redox stabilites are sandwich complexes of the [Re(η6-arene)2]+ type. We report herein routes for conjugating potential ligands to a single or to both arenes in this scaffold. Since the arene rings can freely rotate, the [Re(η6-arene)2]+ has a high degree of structural flexibility. Polypyridyl ligands were successfully introduced. The coordination of Co(II) to such a model tetrapyridyl-Re(I)-bis-benzene complex produced a bimetallic Re(I)–Co(II) complex. To show the stability of the resulting architecture, a selected complex was subjected to photocatalytic reactions. It showed good activity in proton reduction over a long time and did not decompose, corroborating its extraordinary stability even under light irradiation. Its activity compares well with the parent catalyst in turn over numbers and frequencies. The supply of electrons limits catalytic turnover frequency at concentrations below ∼10 μM. We also show that other ligands can be introduced along these strategies. The great diversity offered by [Re(η6-arene)2]+ sandwich complexes from a synthetic point allows this concept to be extended to other catalytic processes, comparable to ferrocenes.

To employ molecular water reduction catalysts (WRC) in a heterogeneous setup, a stable, macrocyclic CoIII–polypyridyl WRC containing two phosphonic acid groups was anchored on TiO2 to investigate photo- and electrocatalytic proton reduction. Photocatalytic investigations included kinetic studies of the electron transfer from the reduced photosensitizer to the WRC as well as H2-evolution measurements. Linear sweep voltammetry (LSV) performed on the immobilized WRC on a TiO2-coated FTO-glass electrode showed an onset potential of −0.6 V vs. SHE at pH = 5 for proton reduction, while operando UV/VIS confirmed the reduced CoI-species as the key catalytic intermediate. Finally, chronoamperometric investigations combined with XPS studies and ICP-MS studies of electrode and electrolyte revealed stable binding of the WRC on the electrode under catalytic conditions and constant H2-formation over the period of two days.

The labeling of (bio)molecules with metallic radionuclides such as 99mTc demands conjugated, multidentate chelators. However, this is not always necessary since phenyl rings can directly serve as integrated, organometallic ligands. Bis‐arene sandwich complexes are generally prepared by the Fischer–Hafner reaction. In extension of this, we show that [99mTc(η6‐C6R6)2]+‐type complexes are directly accessible from water and [99mTcO4]−, even using arenes incompatible with Fischer–Hafner conditions. To unambiguously confirm the nature of these unprecedented 99mTc complexes, their rhenium homologous have been prepared by substituting naphthalene ligands in [Re(η6‐C10H8)2]+ with the corresponding phenyl groups. The ease with which highly stable [99mTc(η6‐C6R6)2]+ complexes are formed under standard labeling conditions enables a multitude of new potential imaging agents based on commercial pharmaceuticals or lead structures.

Pentacarbonyl complexes of 99Tc and Re [M(CAP)(CO)5]X and [M(PTA)(CO)5]X (M = 99Tc or Re and X = ClO4− or OTf–) with aminophosphine ligands 1,4,7-triaza-9-phosphatricyclo[5.3.214,9]tridecane (CAP) and 1,3,5-triaza-7-phosphaadamantane (PTA) were prepared for the first time by the reaction of [MX(CO)5] (M = 99Tc or Re, X = ClO4− or OTf–) with CAP and PTA in CH2Cl2 at room temperature. The reaction of [TcCl(CO)5] with CAP in refluxing CH2Cl2 yields the tricarbonyl complex [99TcCl(CAP)2(CO)3]. Treatment of [Re(H2O)3(CO)3]Cl with CAP in aqueous solution at 40–50 °C gives the rhenium analog [ReCl(CAP)2(CO)3]. Both penta- and tricarbonyl phosphine complexes were characterized by spectroscopic methods (IR, NMR, MS) and single crystal X-ray diffraction. The [M(PTA)(CO)5]X complexes are soluble in aqueous solutions, whereas their CAP analogs are not. The CAP complexes become water-soluble after acidification with dilute acids. As the pH of their aqueous solutions increases, they start to slowly degrade at pH 8 and completely decompose at pH 14. In acidic media, the pentacarbonyl complexes undergo stepwise protonation and are stable indefinitely.

Significant improvements in incident photon-to-current efficiencies can be obtained by covering inorganic semiconductors with ultrathin alumina films and sensitizing them with adsorbed dye molecules. The anchoring mode of the latter to the substrate affects the charge transport between the dye and the electrode via tunneling, and consequently, the device efficiency. In this work, we employ X-ray and ultraviolet photoelectron spectroscopies (XPS and UPS) for a comparative study of the adsorption of three rhenium and two ruthenium organometallic dyes, one of each being ionic, with different anchoring modes on single-crystalline ultrathin alumina films. Molecular monolayers were prepared by self-assembly from solution. Quantitative XPS analysis reveals higher surface densities for the Re dyes. Nearly stoichiometric coadsorption of counterions is observed for the ionic dyes. Density functional theory (DFT) calculations for the Re dyes show that the most stable adsorption configurations exhibit the expected bonding via the dedicated anchoring groups (carboxyls or methylphosphonic acid), with an additional sulfur–aluminum bond for the dyes containing a thiocyanate ligand. The alignment of the occupied molecular levels with respect to the alumina valence band maximum, obtained for these geometries, follows the experimental trend in the UPS data and places the lowest unoccupied molecular orbitals (LUMOs) close to the Fermi level of the systems, far inside the alumina band gap. Dynamical charge screening is found to be important for this type of system when comparing UPS and DFT results. This work provides a general guideline for the systematic characterization of related molecules on surfaces.

A complete set of the symmetrical bidiazine (bdz) and asymmetrical pyridyldiazine (pydz) ligands, along with the known 2,2′‐bipyridyl (bpy) ligand, and their respective rhenium(I)‐tricarbonyl‐bromo and ‐thiocyonato complexes are presented. A bathochromic shift is observed with an increasing number of nitrogen atoms, caused by a stabilization of the diimine based LUMO. As expected from the energy gap law, this results in an increase in the non‐radiative decay constant (knr) along the line bpy‐pydz‐bdz. Interestingly, the increase in knr for both pyridazine ligands (2‐(pyridin‐2‐yl)pyridazine (pypdz) and 3,3′‐bipyridazine (bpdz)) is much less pronounced as compared to the other pydz resp. bdz ligands. This results in overall longer lifetime and quantum yield, at the increased spectral overlap with sunlight – both properties sought for in the creation of light‐harvesting schemes in photochemistry.

The formation of di- or polynuclear complexes at nanomolar concentrations is generally too slow to be observed with 99m Tc. It is reported in this communication that an appropriate choice of potentially bridging ligands, herein thiols HS-R, accelerates the dimerization reaction to an extent that dinuclear complexes are formed at very high dilution. The dinuclear nature of [99m Tc2 (μ2 -SR)3 (CO)6 ]- is shown by chromatographic comparison, not only with its rhenium homologue as commonly done, but also with the true 99 Tc analogue.

Dinitrogen (N

The reductive part of artificial photosynthesis, the reduction of protons into H2, is a two electron two proton process. It corresponds basically to the reactions occurring in natural photosystem I. We show in this review a selection of involved processes and components which are mandatory for making this light-driven reaction possible at all. The design and the performances of the water reduction catalysts is a main focus together with the question about electron relays or sacrificial electron donors. It is shown how an original catalyst is developed into better ones and what it needs to move from purely academic homogeneous processes to heterogeneous systems. The importance of detailed mechanistic knowledge obtained from kinetic data is emphasized.

The oxidation of [Re(η

A series of bifunctional cyclopentadienes of the type 1,3-EtOCO-HCp-linker-NH

Reduction of CO2 to CO and H2O is a two electron/two proton process. For this process, multinuclear complexes offer advantages by concentrating reduction equivalents more efficiently than mononuclear systems. We present novel complexes with [Re(η6‐C6H6)2]+ as scaffold conjugated to one or two catalytically active [Ru(dmbpy)(CO)2Cl2] subunits (dmbpy=5,5′‐dimethyl‐2,2′‐bipyridine). The [Re(η6‐C6H6)2]+ scaffold was chosen due to its very high photo‐ and chemical stability, as well as the multiple degrees of freedom it offers for any conjugated functionalities. High efficiency and selectivity for the reduction of CO2 to CO (over H2 or HCOOH) is reported. TONs and TOFs were found to be comparable or higher than for the catalyst subunit without the rhenium framework. Cooperativity in photo‐ and electrocatalysis is observed for the complex comprising two catalytic subunits. The synergistic communication between the two catalytic subunits is responsible for the observed enhancement in both photo‐ and electrocatalytic performance. Confirmation of electronic communication between the two [Ru(dmbpy)(CO)2Cl2] subunits as well as the elucidation of a possible mechanism was supported by electrochemistry, IR‐spectroelectrochemistry and DFT studies.

Cycloruthenation is a well known process in organometallic ruthenium chemistry. In this work, we report unprecedented cycloruthenated rhenium bis-arene compounds with planar chirality. In a two-step process, the reaction of acetyl-pyridine with [Re(η6-C6H6)2]+ introduced a pyridinyl-methanol ligand at one of the arene rings. Coordination of [Ru(CO)2Cl2] led to cycloruthenation, and the products were obtained as two diastereomeric pairs of enantiomers. Under basic pH conditions, the two pairs of enantiomers undergo spontaneous and reversible dimerization. The cycloruthenated monomers were fully characterized, and the dimerization process was studied by NMR, IR spectroscopy, and DFT calculations.