Acid-Catalyzed Solvent-Switchable Chemoselective -Alkylation and -Alkylation of Unprotected Arylamines Utilizing -Quinone Methides.

Nitrogen-containing compounds, such as anilines, represent some of the most prevalent and valuable chemical entities within the field of chemistry. However, their high reactivity, which frequently lacks selectivity, has constrained their application in various chemical transformations, including the alkylation of alcohols. In the present study, we successfully accomplished site-selective and N-H alkylation of anilines by utilizing -quinone methides under mild conditions.

Strategic design and development of a siderophore mimic: pioneering anticancer therapy ROS generation and ferroptosis.

We designed a tris-catecholate-based siderophore mimic, H-T-CATL, to selectively chelate iron(III) from mitochondrial cytochromes and other iron-containing proteins within cellular matrices. This strategic sequestration aims to trigger apoptosis or ferroptosis in cancer cells through the glutathione (GSH)-dependent release of reduced iron and subsequent ROS-mediated cytotoxicity. Synthesis of H-T-CATL involved precise peptide coupling reactions.

Nondirected, Site-Selective Arylation of Quinone Imine Ketals Derived from Arylamines: One-Pot Access to -Substituted Anilines.

Herein, we develop a metal-free, nondirected, site-selective, one-pot approach to -arylation of arylamines. This Brønsted acid-catalyzed, direct C-C bond formation offers a broad substrate scope and scalability and creates the ideal conditions for overriding the conventional site-selectivity to furnish -substituted anilines. Additionally, the protocol applies to the -allylation of anilines and has been extended to afford late-stage functionalization and synthesis of medicinally privileged arylated diamines and densely functionalized anilines.

Practical Access to meta-Substituted Anilines by Amination of Quinone Imine Ketals Derived from Anisidines: Efficient Synthesis of Anti-Psychotic Drugs.

Reversing the conventional site-selectivity of C-H activation provides efficient retrosynthetic disconnections to otherwise unreactive bonds. Described herein is the Brønsted acid-catalyzed reaction that selectively performs meta-amination of anisidines with aliphatic-, heterocyclic- and aromatic amines in a one-pot procedure. In addition to dramatically simplifying the synthesis of meta-substituted anilines, our approach has the advantage of the scalability and remarkable functional group tolerance, including late-stage functionalization of pharmaceutical compounds and natural products.

Red light-activable biotinylated copper(II) complex-functionalized gold nanocomposite (Biotin-Cu@AuNP) towards targeted photodynamic therapy.

We report the synthesis and characterization of red-light activable gold nanoparticle functionalized with biotinylated copper(II) complex of general molecular formula, [Cu(L)(L)]-AuNPs (Biotin-Cu@AuNP), where L = N-(3-((E)-3,5-di-tert-butyl-2-hydroxybenzylideneamino)-4-hydroxyphenyl)-5-((3aS,4S,6aR)-2-oxo-hexahydro-1H-thieno[3,4-d]imidazol-4-yl)pentanamide, L = 5-(1,2-dithiolan-3-yl)-N-(1,10-phenanthrolin-5-yl)pentanamide, which was explored for their photophysical, theoretical and photo-cytotoxic potentials. The nanoconjugate exhibits differential uptake in biotin positive and biotin negative cancer cells as well as normal cells. The nanoconjugate also shows remarkable photodynamic activity against biotin positive A549 (IC: 13 μg/mL in red light; >150 μg/mL in dark) and HaCaT (IC: 23 μg/mL in red light; >150 μg/mL in dark) cells under red light (600-720 nm, 30 Jcm) irradiation, with significantly high photo-indices (PI>15).

DDQ/Fe(NO)-Catalyzed Aerobic Synthesis of 3-Acyl Indoles and an In Silico Study for the Binding Affinity of -Tosyl-3-acyl Indoles toward RdRp against SARS-CoV-2.

In the present study, we herein report a DDQ-catalyzed new protocol for the synthesis of substituted 3-acylindoles. Being a potential system for virtual hydrogen storage, introduction of catalytic DDQ in combination with Fe(NO)·9HO and molecular oxygen as co-catalysts offers a regioselective oxo-functionalization of C-3 alkyl-/aryllidine indolines even with scale-up investigations. Intermediate isolation, their spectroscopic characterization, and the density functional theory calculations indicate that the method involves dehydrogenative allylic hydroxylation and 1,3-functional group isomerization/aromatization followed by terminal oxidation to afford 3-acylindoles quantitatively with very high regioselectivity.

Transition-Metal-Free Transfer Hydrogenative Cascade Reaction of Nitroarenes with Amines/Alcohols: Redox-Economical Access to Benzimidazoles.

This report describes an efficient transition-metal-free process toward the transfer hydrogenative cascade reaction between nitroarenes and amines or alcohols. The developed redox-economical approach was realized using a combination of KOBu and EtSiH as reagents, which allows the synthesis of benzimidazole derivatives via σ-bond metathesis. The reaction conditions hold well over a wide range of substrates embedded with diverse functional groups to deliver the desired products in good to excellent yields.

Computational Studies of Selected Transition Metal Complexes as Potential Drug Candidates against the SARS-CoV-2 Virus.

The earth has witnessed the greatest global health crisis due to the outbreak of the SARS-CoV-2 virus in late 2019, resulting in the pandemic COVID-19 with 3.38 million mortality and 163 million infections across 222 nations. Therefore, there is an urgent need for an effective therapeutic option against the SARS-CoV-2 virus.

A noncovalent hybrid of [Pd(phen)(OAc)] and st-DNA for the enantioselective hydroamination of β-nitrostyrene with methoxyamine.

We developed a novel Pd-catalysed enantioselective synthesis of C-N bonds using the chiral scaffold of DNA. The non-covalently linked [Pd(phen)(OAc)2] with st-DNA catalysed the Markonicov hydroamination of β-nitrostyrene with methoxyamine for the first time with >75% enantiomeric excess (ee) in an aqueous buffer (pH 7.4) at room temperature.

Iron(III) Complex-Functionalized Gold Nanocomposite as a Strategic Tool for Targeted Photochemotherapy in Red Light.

Iron(III)-phenolate/carboxylate complexes exhibiting photoredox chemistry and photoactivated reactive oxygen species (ROS) generation at their ligand-to-metal charge-transfer (LMCT) bands have emerged as potential strategic tools for photoactivated chemotherapy. Herein, the synthesis, in-depth characterization, photochemical assays, and remarkable red light-induced photocytotoxicities in adenocarcinomic human immortalized human keratinocytes (HaCaT) and alveolar basal epithelial (A549) cells of iron(III)-phenolate/carboxylate complex of molecular formula, [Fe(L)(L)] (), where L is bis(3,5 di--butyl-2-hydroxybenzyl)glycine and L is 5-(1,2-dithiolan-3-yl)--(1,10-phenanthroline-5-yl)pentanamide, and the gold nanocomposite functionalized with complex (-AuNPs) are reported. There was a significant red shift in the UV-visible absorption band on functionalization of complex to the gold nanoparticles (λ: 573 nm, ; λ: 660 nm, -AuNPs), rendering the nanocomposite an ideal candidate for photochemotherapeutic applications.

Interfacial and Aggregation Behaviour of Sodium Dodecyl Sulphate Induced by Ionic Liquids.

Aggregation studies of anionic surfactant sodium dodecyl sulphate (SDS) was investigated in aqueous 1-butyl-3-methylimidazolium chloride [bmim]Cl and N-butyl-N-methyl pyrrolidinium tetrafluoroborate [bmp]BF ionic liquid (IL) solutions respectively. Systems were studied by surface tension, conductance, UV-VIS absorption/emission spectroscopy and dynamic light scattering. Critical micelle concentration (CMC) values gradually decreased with increasing IL concentration which indicates synergistic interaction between ILs and SDS.

Photo-physical, theoretical and photo-cytotoxic evaluation of a new class of lanthanide(iii)-curcumin/diketone complexes for PDT application.

Herein we report the synthesis, characterization, photophysical and photocytotoxicity studies of a new class of curcumin-based lanthanide(iii) complexes of general molecular formula [La(1,10-phen)2(L)(NO3)2] (1-4), where L = 1-phenylbutane-1,3-dione (L1, 1), 1-(anthracen-9-yl)butane-1,3-dione (L2, 2), 1-(3a1,5a1-dihydropyren-1-yl)butane-1,3-dione (L3, 3) and curcumin (L4, 4). Complex 1 was characterized by single-crystal X-ray crystallography and it exhibited the N4O6 coordination of La(iii). The presence of the low-lying and long-lived triplet excited state enabled the luminescent complexes (2-4) to generate singlet oxygen (1O2) in high yield when the complex was activated with visible light (400-700 nm, 10 J cm-2), which could be responsible for the photo-ablation of cancer cells.

New Selenonapthaquinone-Based Copper (II) Complexes as the Next-Generation Photochemotherapeutic Agents.

Background And Objective: Photoactive transition metal complexes like copper complexes find great interest in promoting metal-based photochemotherapeutic agents. In the present study, we explored the photocytotoxic efficacy of new selenylnaphthoquinone-based copper (II) complexes that provide a phenomenal platform in making an effective photo-chemotherapeutic agent via PDT in the clinical field of cancer therapy.

Methods: Three new copper(II) complexes (1-3) were synthesized in 40-60% yield and characterized analytically/ spectroscopically.