Silver-purine MOFs for high-performance multi-terminal neuromorphic memory.

Neuromorphic and fully analog in-memory computations are promising for handling vast amounts of data with minimal energy consumption. We have synthesized and studied a series of homo-bimetallic silver purine MOFs (1D and 2D) having direct metal-metal bonding. The N7-derivatized purine ligands are designed to form bi-metallic complexes under ambient conditions, extending to a 1D or 2D metal-organic framework.

TTFA-Platin Conjugate: Deciphering the Therapeutic Roles of Combo-Prodrug through Evaluating Stability-Activity Relationship.

This work introduces a novel Pt(II) based prodrug TTFA-Platin that integrates a β-diketonate ligand TTFA with a platinum scaffold to structurally resemble carboplatin and offers intermediate kinetic lability between cisplatin and carboplatin, striking a balance between therapeutic efficacy and safety. A comprehensive stability and speciation study was conducted in various biological media, mapping the therapeutic effects of TTFA-Platin. A control molecule, TMK-Platin, was synthesized to further validate the structural-stability relationship, which displayed poor activatable features in biological systems.

Bipyridyl Functionalized NHC-Sulfenyl, Selenenyl Cations; Potential Species for Alkylation Reactions and Ligands in Copper(I) Catalysis.

Reactions of bipyridyl-functionalized imidazole-thiones and selones with MeX (X=I, OTf) afforded sulfenyl and selenenyl cations [(NNC)EMe]X (2/3, E=S, Se). Further reactions of these main-group cations with [Cu(CHCN)]BF, Cu(OTf) furnished dicationic [{Cu(μ-I)(NNC)EMe}][Y] (5/6, Y=BF, OTf) and tricationic copper(I) complexes [Cu{(NNC)EMe}](OTf)BF (7 a/7 b) when employed [(NNC)EMe]I and [(NNC)EMe]OTf respectively. All these cationic complexes were characterized by various spectroscopic techniques, including X-ray diffraction analysis.

Deciphering Electrocatalytic Hydrogen Production in Water Through a Bioinspired Water-Stable Copper(II) Complex Adorned with (NS)-Donor Sites.

Electrocatalytic hydrogen production stands as a pivotal cornerstone in ushering the revolutionary era of the hydrogen economy. With a keen focus on emulating the significance of hydrogenase-like active sites in sustainable H generation, a meticulously designed and water-stable copper(II) complex, [Cl-Cu-L]ClO, featuring the N,S-type ligand, L (2,2'-((butane-2,3-diylbis(sulfanediyl))bis(methylene))dipyridine), has been crafted and assessed for its prowess in electrocatalytic H production in water, leveraging acetic acid as a proton source. The molecular catalyst, adopting a square pyramidal coordination geometry, undergoes -Cl substitution by HO during electrochemical conditions yielding [HO-Cu-L] as the true catalyst, showcases outstanding activity in electrochemical proton reduction in acidic water, achieving an impressive rate of 241.

Decrypting the hydrogen evolution in alkaline water with novel magnetoactive cobalt(II) complex-driven cobalt oxide electrocatalysts.

Under the gravity of future socio-economic development, the viability of water electrolysis still hinges on the accessibility of stable earth-abundant electrocatalysts and net energy efficiency. This work emphasizes the design and synthesis of two newly developed cobalt(II) complexes, [Co(HL)(NCS)] (Comono) and [Co(L)(CHOH)]ClO (Codi), with a (N,O)-donor ligand, HL (2-methoxy-6-(((2-methoxyphenyl)imino)methyl)phenol). The study delves into understanding their structural, morphological, magnetic, and charge transport characteristics.

Phenalenyl-ruthenium synergism for effectual catalytic transformations of primary amines to amides.

The synthesis of amides holds great promise owing to their impeccable contributions as building blocks for highly valued functional derivatives. Herein, we disclose the design, synthesis and crystal structure of a mixed-ligand ruthenium(II) complex, [Ru(η-Cym)(O,O-PLY)Cl], (1) where Cym = 1-isopropyl-4-methyl-benzene and O,O-PLY = deprotonated form of 9-hydroxy phenalenone (HO,O-PLY). The complex catalyzes the aerobic oxidation of various primary amines (RCHNH) to value-added amides (RCONH) with excellent selectivity and efficiency under relatively mild conditions with common organic functional group tolerance.

NHC Ligand-Enabled Cu(I)-Catalyzed Double Hydroamination: A Regio- and Chemoselective Bicyclization of -Amino 1,6-Diyne.

In this work, we have developed an efficient method for the intramolecular double hydroamination of aniline by employing -amino 1,6-diyne as a potential starting material. This protocol enables easy access to bioactive motif 3,4-dihydro-1-[1,4]oxazino[4,3-]indole through an intramolecular cascade bicyclization and concomitant isomerization pathway in one pot. This transformation has been effectively achieved by utilizing a stereoelectronically tuned, π-accepting NHC-supported copper(I) system.

Template Assisted Synthesis of Linear [5]Catenane by Post-Functionalization of Templated [2]Catenane and Using Click Reaction.

Polymers with all mechanically interlocked rings, such as linear [n]catenanes, have great potential as functional materials due to possible higher degrees of freedom that may contribute to their flexibility but remain elusive. All the synthetic methods used to prepare such a polymer yield mixtures of products. In the absence of higher molecular weight linear [n]catenanes, emphasis on synthesizing low molecular weight oligomers is being pursued.

Template Assisted One-Pot Synthesis of [2], Linear [3], and Radial [4]Catenane via Click Reaction.

Design and synthesis of higher order catenane are unexpectedly complex and involve precise cooperation among the precursors overcoming competing and opposing interactions. We achieved synthesis of [2], linear [3], radial [4] in a one-pot reaction by consecutive ring closing through click reactions. This synthesis gave three isolable products due to two, four, and six-click reactions between suitable coupling partners.

New cationic coinage metal complexes featuring silyl group functionalized phosphine: syntheses, structures and catalytic studies in alkyne-azide cycloaddition reactions.

A series of coinage metal complexes bearing rarely explored -silylated phosphine is reported. The treatment of diphenyl(2-(trimethylsilyl)phenyl)phosphine (1) with CuCl and [Cu(CHCN)]BF furnished the corresponding neutral [(1)CuCl] (2) and mono-cationic [(1)Cu(CHCN)]BF (3) complexes, respectively. The reactions of 1 with AgX (X = BF, NO) in 2 : 1 ratio furnished the corresponding mono cationic dicoordinate silver(I) complexes of the type [(1)Ag]X (X = BF (4a), NO (4b)).

Dicationic copper(I) complexes bearing ENE (E = S, Se) pincer ligands; catalytic applications in regioselective cyclization of 1,6-diynes.

Two novel dicationic binuclear Cu(I) complexes of the type [{(BPPP)E}Cu][BF] (E = S (3a); Se (3b)) bearing (BPPP)E (BPPP = bis(diphenylphosphino)pyridine) pincer systems were isolated, and structurally characterized. The solid-state structures of 3a/3b display the presence of intermolecular cuprophilic (Cu⋯Cu) interactions between the two monocationic species, and consist of weak Cu⋯S bonding between the two cations. Besides, complex 3a was introduced as a molecular copper(I) catalyst in cyclization reactions, and new protocols were developed for the synthesis of a series of new oxazole and triazole derivatives bearing alkyne-phenyl propargylic ether substituents.

Harnessing the hydrogen evolution reaction (HER) through the electrical mobility of an embossed Ag(I)-molecular cage and a Cu(II)-coordination polymer.

A structurally characterized porous Ag(I)-molecular cage Ag and a Cu(II)-coordination polymer Cu with a pre-synthesized ligand 1,3-bis((()-2-methoxybenzylidene)amino)propan-2-ol and its parental amine with thiocyanate are reported to harness electrical mobility-driven hydrogen evolution activity. Porosity-induced electrically conductive Ag emerges as a better electrocatalyst with a Tafel slope of 104 mV per decade over Cu(II)-polymer's slope of 128 mV per decade. The electrochemical stability and durability of the designed electrocatalysts in harnessing the HER activity are also examined under experimental conditions.

Ligand-metal cooperativity in quinonoid based nickel(II) and cobalt(II) complexes for catalytic hydrosilylative reduction of nitriles to amines: electron transfer and mechanistic insight.

The sustainable production of privileged amines by the catalytic reduction of nitriles with an inexpensive silane polymethylhydrosiloxane (PMHS) holds great promise to replace conventional synthetic routes that have limited applicability and involve the use of expensive metal catalysts. The use of late 3d-metal complexes provides an excellent platform for the rational design of inexpensive catalysts with exquisite control over their electronic and structural features through metal-ligand cooperativity. In this context, we have realistically designed two complexes based on nickel(II) and cobalt(II) with a redox-active imino--benzoquinonato ligand.

anti-SARS-CoV-2 activities of five-membered heterocycle-substituted benzimidazoles.

The manuscript deals with cost-effective synthesis, structural characterization and SARS-CoV-2 screening activity of 5-membered heterocycle-substituted benzimidazole derivatives, 1-((1H-pyrrol-2-yl)methyl)-2-(1H-pyrrol-2-yl)-1H-benzo[d]imidazole (), 2-(furan-2-yl)-1-(furan-2-ylmethyl)-1H-benzo[d]imidazole (), 2-(thiophen-2-yl)-1-(thiophen-2-ylmethyl)-1H-benzo[d]imidazole (). The benzimidazole compounds were synthesized through a green-synthetic approach by coupling of 5-membered heterocyclic-carboxaldehyde and o-phenylenediamine in water under an aerobic condition. The compounds were characterized by various spectroscopic methods and X-ray structural analysis.

Correction: Synthesis of medium-sized (6-7-6) ring compounds by iron-catalyzed C-H activation/annulation.

Correction for 'Synthesis of medium-sized (6-7-6) ring compounds by iron-catalyzed dehydrogenative C-H activation/annulation' by Niranjan Panda et al., Org. Biomol.

Base mediated green synthesis of enantiopure 2-C-spiro-glycosyl-3-nitrochromenes.

A novel green synthetic methodology has been developed to obtain enantiopure (2S)-2-C-spiro-glycosyl-3-nitrochromenes following the oxa-Michael-aldol condensation reaction of sugar derived 3-C-vinyl nitro olefins with substituted salicylaldehydes using Et3N as a base under neat conditions at rt-40 °C. The stereochemistry of the product is confirmed by a single crystal X-ray study. Several advantages are associated with this protocol such as cost effectiveness, easy accessibility, short reaction time, high yields, wide substrate scope and high enantiopurity.

Synthesis of medium-sized (6-7-6) ring compounds by iron-catalyzed C-H activation/annulation [corrected].

In this report, we have described a FeCl3-catalyzed process involving intramolecular annulation of o-phenoxy diarylacetylenes via hydroarylation to afford a series of biologically potent fused seven-membered (6-7-6) ring compounds under mild reaction conditions. This reaction was believed to proceed through Friedel-Crafts type sequential carbometallation followed by protonation to produce phenyldibenz[b,f]oxepines. This method was also extended to synthesize seven-membered rings that are fused with coumarins.

Semi-insulating behaviour of self-assembled tin(IV)corrole nanospheres.

Three novel tin(iv)corrole complexes have been prepared and characterized by various spectroscopic techniques including single crystal X-ray structural analysis. Packing diagrams of the tin(iv)corroles revealed that corrolato-tin(iv)-chloride molecules are interconnected by intermolecular C-HCl hydrogen bonding interactions. HCl distances are 2.

Synthesis, spectral characterization, structures, and oxidation state distributions in [(corrolato)Fe(III)(NO)](n) (n = 0, +1, -1) complexes.

Two novel trans-A2B-corroles and three [(corrolato){FeNO}(6)] complexes have been prepared and characterized by various spectroscopic techniques. In the native state, all these [(corrolato){FeNO}(6)] species are diamagnetic and display "normal" chemical shifts in the (1)H NMR spectra. For two of the structurally characterized [(corrolato){FeNO}(6)] derivatives, the Fe-N-O bond angles are 175.

Tetra-kis-(μ-3-meth-oxy-benzoato-κO:O)bis[acetonitrilecopper(II)].

The centrosymmetric binuclear Cu(II) title complex, [Cu(2)(C(8)H(7)O(3))(4)(CH(3)CN)(2)], has a paddle-wheel-type structure [Cu-Cu distance = 2.6433 (3) Å]. Each Cu(II) ion is coordin-ated by four O atoms from two 3-meth-oxy-benzoate ligands and one acetonitrile N atom in a square-pyramidal geometry.

A double-stranded DNA rotaxane.

Mechanically interlocked molecules such as rotaxanes and catenanes have potential as components of molecular machinery. Rotaxanes consist of a dumb-bell-shaped molecule encircled by a macrocycle that can move unhindered along the axle, trapped by bulky stoppers. Previously, rotaxanes have been made from a variety of molecules, but not from DNA.

Mannosylated self-assembled structures for molecular confinement and gene delivery applications.

This paper reports self-assembly of a lysine conjugated with a biantennary mannose to form spherical structures. These supramolecular structures are found to be hollow in nature and they afford effective encapsulation of alkaline phosphatase enzyme, plasmid DNA and a GFP reporter gene, which was transfected in COS-7 cells. Loaded hollow structures also get disrupted upon mild sonication, releasing encapsulated molecules thereby illustrating their potential for confinement and delivery applications.

Directing spatial disposition of ferrocene around homoadenine tetrads.

We report synthesis and crystallographic studies of a ferrocenyl conjugate of adenine, where the hydrogen bonding interactions promote and stabilize nucleobase homotetrad formation.

Four-stranded coordination helices containing silver-adenine (purine) metallaquartets.

This Communication describes structures of a family of silver-adenine (purine) metallaquartets that occur in a four-stranded coordination motif, bearing a close resemblance to nucleic acid quadruplexes. Using modified purine frameworks, it is further demonstrated that subtle variations in nucleobase heterocycle are tolerable and a metallaquartet is obtained irrespective of the substitution, thus suggesting a high-propensity silver-adenine interaction to achieve quartet structures. All of the solid-state structures studied were orthorhombic, belonging to the Fdd2 space group.

Close contacts between carbonyl oxygen atoms and aromatic centers in protein structures: pi...pi or lone-pair...pi interactions?

Lone-pair...