C1-4 Alkylation of Aryl Bromides with Light Alkanes enabled by Metallaphotocatalysis in Flow.

The homologous series of gaseous C1-4 alkanes represents one of the most abundant sources of short alkyl fragments. However, their application in synthetic organic chemistry is exceedingly rare due to the challenging C-H bond cleavage, which typically demands high temperatures and pressures, thereby limiting their utility in the construction of complex organic molecules. In particular, the formation of C(sp)-C(sp) bonds is crucial for constructing biologically active molecules, including pharmaceuticals and agrochemicals.

Correction: Not antiaromaticity gain, but increased asynchronicity enhances the Diels-Alder reactivity of tropone.

Correction for 'Not antiaromaticity gain, but increased asynchronicity enhances the Diels-Alder reactivity of tropone' by Eveline H. Tiekink , , 2023, , 3703-3706, https://doi.org/10.

6-Aryl-4-cycloamino-1,3,5-triazine-2-amines: synthesis, antileukemic activity, and 3D-QSAR modelling.

Despite significant progress in immunotherapy and chimeric antigen receptor T cell therapy of leukemia, chemotherapy is the major treatment option for the disease. Therefore, the development of potent and safe drugs for standard and targeted chemotherapy of leukemia remains an important task for medicinal chemists. A library of 94 diverse 6-aryl-4-cycloamino-1,3,5-triazine-2-amines was prepared using a one-pot microwave-assisted protocol, which involves a three-component reaction of cyanoguanidine, aromatic aldehydes and cyclic amines, and subsequent dehydrogenative aromatization of the dihydrotriazine intermediates in the presence of alkali.

Discovery of indoleninyl-pyrazolo[3,4-b]pyridines as potent chemotherapeutic agents against colorectal cancer cells.

A new series of indolenines decorated with pyrazolo[3,4-b]pyridines were designed and synthesized in up to 96% yield from the acid-catalyzed cyclocondensation of 1,3-dialdehydes with 3-aminopyrazoles. X-ray crystallography on a representative derivative, 5n, revealed two close to planar conformations whereby the N-atom of the pyridyl residue was syn or anti to the pyrrole-N atom in the two independent molecules of the asymmetric unit. The computational and DNA binding data suggest that 5n is a strong DNA intercalator with the results in agreement with its potent cytotoxicity against two colorectal cancer cell lines (HCT 116 and HT-29).

Synthesis and Staphylococcus aureus biofilm inhibitory activity of indolenine-substituted pyrazole and pyrimido[1,2-b]indazole derivatives.

Staphylococcus aureus is a highly adaptable opportunistic pathogen that can form biofilms and generate persister cells, leading to life-threatening infections that are difficult to treat with antibiotics alone. Therefore, there is a need for an effective S. aureus biofilm inhibitor to combat this public health threat.

Structural insights and cytotoxicity evaluation of benz[e]indole pyrazolyl-substituted amides.

Five new compounds of benz[e]indole pyrazolyl-substituted amides (2a-e) were synthesised in low to good yields via the direct amide-coupling reaction between a pyrazolyl derivative containing a carboxylic acid and several amine substrates. The molecular structures were determined by various spectroscopic methods, such as NMR (H, C and F), FT-IR and high-resolution mass spectrometry (HRMS). X-ray crystallographic analysis on the 4-fluorobenzyl derivative (2d) reveals the amide-O atom to reside to the opposite side of the molecule to the pyrazolyl-N and pyrrolyl-N atoms; in the molecular packing, helical chains feature amide-N‒H⋯N(pyrrolyl) hydrogen bonds.

Synthesis, spectral characterisation, biocidal investigation, and molecular docking studies of 4-[(2-chloro-4-methylphenyl)carbamoyl]butanoic acid derived triorganotin(IV) compounds.

Three triorganotin(IV) compounds, RSn(L), with R = CH (), -CH () and CH (), and LH = 4-[(2-chloro-4-methylphenyl)carbamoyl]butanoic acid, were prepared and confirmed by various techniques. A five-coordinate, distorted trigonal-bipyramidal geometry was elucidated for tin(IV) centres both in solution and solid states. An intercalation mode was confirmed for the compound SS-DNA interaction by UV-visible, viscometric techniques and molecular docking.

The Origin of Catalysis and Regioselectivity of Lewis Acid-Catalyzed Diels-Alder Reactions with Tropone.

We have studied the uncatalyzed and Lewis acid (LA)-catalyzed cycloaddition reaction between tropone and 1,1-dimethoxyethene using dispersion-corrected relativistic density functional theory (DFT). The LA catalysts BF , B(C H ) , and B(C F ) efficiently accelerate both the competing [4+2] and [8+2] cycloaddition reactions by lowering the activation barrier up to 12 kcal mol compared to the uncatalyzed reaction. Our study reveals that the LA catalyst promotes both cycloaddition reaction pathways by LUMO-lowering catalysis and demonstrates that Pauli-lowering catalysis is not always the operative catalytic mechanism in cycloaddition reactions.

Synthetic strategies and diversification of dibenzo[1,5]diazocines.

Dibenzo[1,5]diazocine scaffolds are present in a wide range of organic building blocks, for example in pharmaceuticals, materials and structural chemistry. However, the development of these structural frameworks has not received significant attention owing to limited synthetic protocols and strategies. Herein, a summary of the attractive synthetic approaches for the construction of dibenzo[1,5]diazocines, epiminodibenzo[1,5]diazocines and epoxydibenzo[1,5]diazocines developed over the past two decades is presented.

Not antiaromaticity gain, but increased asynchronicity enhances the Diels-Alder reactivity of tropone.

Tropone is an unreactive diene in normal electron demand Diels-Alder reactions, but it can be activated carbonyl umpolung by using hydrazone ion analogs. Recently, the higher reactivity of hydrazone ion analogs was ascribed to a raised HOMO energy induced by antiaromaticity (L. J.

How Bases Catalyze Diels-Alder Reactions.

We have quantum chemically studied the base-catalyzed Diels-Alder (DA) reaction between 3-hydroxy-2-pyrone and N-methylmaleimide using dispersion-corrected density functional theory. The uncatalyzed reaction is slow and is preceded by the extrusion of CO via a retro-DA reaction. Base catalysis, for example, by triethylamine, lowers the reaction barrier up to 10 kcal mol , causing the reaction to proceed smoothly at low temperature, which quenches the expulsion of CO , yielding efficient access to polyoxygenated natural compounds.

Cadmium(II) compounds of the bis-cyanoethyl derivative (L) of Me[14]aneC (L): characterization and antibacterial studies.

The isomeric ligand L, a saturated analogue of 2,9-C-meso-Me[14]diene, on reflux with excess acrylonitrile afforded 1,8-N-pendant cyanoethyl derivative L. Interaction of L with cadmium(II) perchlorate, nitrate, acetate, and chloride salts produced six coordinated octahedral compounds, [Cd(L) (ClO)]∙2HO, [Cd(L) (NO)], [Cd(L) (CHCOO)], and [Cd(L)Cl], respectively. Further, axial substitution reactions between [Cd(L) (ClO)]∙2HO and KI, KBr, KCl, KSCN, and NaNO in a 1:2 ratio yielded six coordinated octahedral compounds, [Cd(L)I]∙HO, [Cd(L)Br]∙2HO, [Cd(L)Cl(ClO)]∙2HO, [Cd(L) (NCS)]∙HO, and [Cd(L) (NO) (ClO)]∙2HO, respectively.

Indoleninyl-substituted pyrimido[1,2-]indazoles a facile condensation reaction.

A new series of pyrimido[1,2-]indazoles bearing indolenine moieties was synthesized through a simple condensation reaction with up to 94% yield. The present method features the versatile formation of a pyrimidine ring with a broad range of substrates, great functional group compatibility and facile synthetic operation. The work offers opportunities in drug development as well as in materials science.

Three-component microwave-assisted synthesis of 3,5-disubstituted pyrazolo[3,4-]pyrimidin-4-ones.

A practical three-component method for the synthesis of pyrazolo[3,4-]pyrimidin-4-ones was developed. The reaction was performed in a one-pot manner under controlled microwave irradiation using easily accessible methyl 5-aminopyrazole-4-carboxylates, trimethyl orthoformate, and primary amines. Under the optimized conditions, challenging substrates, such as N-1 unsubstituted 5-aminopyrazole-4-carboxylates with another substituted amino group in position 3, reacted selectively affording 5-substituted 3-arylamino-1,5-dihydro-4-pyrazolo[3,4-]pyrimidin-4-ones.

[-1,8-Bis(2-carbamoyleth-yl)-5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-aza-cyclo-tetra-deca-ne]copper(II) di-acetate tetra-hydrate: crystal structure and Hirshfeld surface analysis.

The title Cu macrocyclic complex salt tetra-hydrate, [Cu(CHNO)](CHO)·4HO, sees the metal atom located on a centre of inversion and coordinated within a 4 + 2 (NO) tetra-gonally distorted coordination geometry; the N atoms are derived from the macrocycle and the O atoms from weakly associated [3.2048 (15) Å] acetate anions. Further stability to the three-ion aggregate is provided by intra-molecular amine-N-H⋯O(carboxyl-ate) hydrogen bonds.

Water-Soluble Dioxidovanadium(V) Complexes of Aroylhydrazones: DNA/BSA Interactions, Hydrophobicity, and Cell-Selective Anticancer Potential.

Five new anionic aqueous dioxidovanadium(V) complexes, [{VOL}A(HO)] (-), with the aroylhydrazone ligands pyridine-4-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)hydrazide (HL) and furan-2-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)hydrazide (HL) incorporating different alkali metals (A = Na, K, Cs) as countercation were synthesized and characterized by various physicochemical techniques. The solution-phase stabilities of - were determined by time-dependent NMR and UV-vis, and also the octanol/water partition coefficients were obtained by spectroscopic techniques. X-ray crystallography of - confirmed the presence of vanadium(V) centers coordinated by two -oxido-O atoms and the O, N, and O atoms of a dianionic tridentate ligand.

Bis{'-[3-(4-nitro-phen-yl)-1-phenyl-prop-2-en-1-yl-idene]--phenyl-carbamimido-thio-ato}zinc(II): crystal structure, Hirshfeld surface analysis and computational study.

The title zinc bis-(thio-semicarbazone) complex, [Zn(CHNOS)], comprises two ,-donor anions, leading to a distorted tetra-hedral NS donor set. The resultant five-membered chelate rings are nearly planar and form a dihedral angle of 73.28 (3)°.

1-{()-[4-(4-Hy-droxy-phen-yl)butan-2-yl-idene]amino}-3-phenyl-thio-urea: crystal structure, Hirshfeld surface analysis and computational study.

The title thio-urea derivative, CHNOS, adopts a U-shaped conformation with the dihedral angle between the terminal aromatic rings being 73.64 (5)°. The major twist in the mol-ecule occurs about the ethane bond with the C-C-C-C torsion angle being -78.

Di--but-yl['-(3-meth-oxy-2-oxidobenzyl-idene)--phenyl-carbamohydrazono-thio-ato]tin(IV): crystal structure, Hirshfeld surface analysis and computational study.

The title diorganotin Schiff base derivative, [Sn(CH)(CHNOS)], features a penta-coordinated tin centre defined by the N,,-donor atoms of the di-anionic Schiff base ligand and two methyl-ene-C atoms of the -butyl substituents. The resultant CNOS donor set defines a geometry inter-mediate between trigonal-bipyramidal and square-pyramidal. In the crystal, amine-N-H⋯O(meth-oxy) hydrogen bonding is found in a helical, supra-molecular chain propagating along the -axis direction.

Ethyl 3,4-bis-(acet-yloxy)-2-(4-meth-oxy-phen-yl)pyrrol-idine-1-carboxyl-ate.

The title pyrrolidine compound, CHNO, is a tetra-substituted species in which the five-membered ring has a twisted conformation with the twist occurring in the C-C bond bearing the adjacent acet-yloxy substituents; the C-C-C-C torsion angle is -40.76 (18)° [m = methyl-ene, a = acet-yloxy and p = phen-yl]. The N atom, which is -hybridized [sum of bond angles = 359.

Zero-, one-, two- and three-dimensional supramolecular architectures sustained by SeO chalcogen bonding: A crystallographic survey.

The Cambridge Structural Database was evaluated for crystals containing SeO chalcogen bonding interactions. These secondary bonding interactions are found to operate independently of complementary intermolecular interactions in about 13% of the structures they can potentially form. This number rises significantly when more specific interactions are considered, e.

[()--(3-Fluoro-phen-yl)--methyl-thio-carbamato-κ](tri-phenyl-phosphane-κ)gold(I): crystal structure, Hirshfeld surface analysis and computational study.

The title phosphanegold(I) thiol-ate, CHAuFNOPS or [Au(CHFNOS)(CHP)], has the Au centre coordinated by phosphane-P [2.2494 (8) Å] and thiol-ate-S [2.3007 (8) Å] atoms to define a close to linear geometry [P-Au-S = 176.

2-[(1)-[()-2-({[(1)-[()-2-[(2-Hy-droxy-phen-yl)methyl-idene]hydrazin-1-yl-idene]({[(4-methyl-phen-yl)meth-yl]sulfan-yl})meth-yl]disulfan-yl}({[(4-methyl-phen-yl)meth-yl]sulfan-yl})methyl-idene)hydrazin-1-yl-idene]meth-yl]phenol: crystal structure, Hirshfeld surface analysis and computational study.

The complete mol-ecule of the title hydrazine carbodi-thio-ate derivative, CHNOS, is generated by a crystallographic twofold axis that bis-ects the di-sulfide bond. The mol-ecule is twisted about this bond with the C-S-S-C torsion angle of 90.70 (8)° indicating an orthogonal relationship between the symmetry-related halves of the mol-ecule.