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The reactivity of Morita–Baylis–Hillman Adduct (MBHA) derivative 7 was studied with different primary amine derivatives such as n‐butylamine, Nα‐acetyl‐L‐lysine methyl ester, and a poly‐(L‐lysine) derivative as lysine models to obtain information about the possible reactions in complex protein environments. MBHA derivative 7 reacted with n‐butylamine or Nα‐acetyl‐L‐lysine methyl ester producing monoadducts 9a or 9c, which showed bright emission features in the green region at 526–535 nm with photoluminescence quantum yield values in solutions of 73 % and 51 %, respectively. Based on these results, MBHA derivative 7 can be considered an interesting new fluorogenic probe potentially useful in the labelling of basic amino acid residues. Furthermore, similar to other MBHA derivatives, compound 7 showed the tendency to produce diadducts especially in polar solvents system where specific interactions between the extended aromatic moieties may play a major role. [ABSTRACT FROM AUTHOR]

In this paper, a direct access to benzylic amines from in‐situ generated ortho‐quinone methides (o‐QMs) and isocyanate/isothiocyanate via decarboxylation is described. This base‐catalyzed methodology has high functional group tolerance and shows a wide range of substrate scopes, where H2O as a nucleophile for isocyanate/isothiocyanate for product formation. The products are insensitive to air and moisture, which makes this synthetic strategy more efficient for the construction of various benzyl amine derivatives. [ABSTRACT FROM AUTHOR]

Herein we demonstrate an "in‐ring establishing" strategy for assembling interlocked molecules through dynamic imine formation, "establishing" the host recognition sites in situ. Using Zn2+ ions to template the assembly of a pyridine‐containing macrocycle with semidumbbell‐shaped triazole‐containing aldehyde and amine derivatives, we obtained the corresponding [2]rotaxane in high yield (85 %) after subsequent imine reduction (NaBH4) and amine protonation (NH4PF6). We performed the same three steps (assembly, reduction, protonation) to prepare a stable and highly symmetrical [5]molecular necklace ([5]MN) from 12 components (two almost‐90°‐oriented dialdehydes, two almost‐90°‐oriented diamines, four macrocycles, four Zn2+ ions) in an overall yield of 69 %. [ABSTRACT FROM AUTHOR]

A series of new unique acetylene derivatives of 8-hydroxy- and 8-methoxyquinoline- 5-sulfonamide 3a–f and 6a–f were prepared by reactions of 8-hydroxy- and 8-methoxyquinoline- 5-sulfonyl chlorides with acetylene derivatives of amine. A series of new hybrid systems containing quinoline and 1,2,3-triazole systems 7a–h were obtained by reactions of acetylene derivatives of quinoline-5-sulfonamide 6a–d with organic azides. The structures of the obtained compounds were confirmed by 1H and 13C NMR spectroscopy and HR-MS spectrometry. The obtained quinoline derivatives 3a–f and 6a–f and 1,2,3-triazole derivatives 7a–h were tested for their anticancer and antimicrobial activity. Human amelanotic melanoma cells (C-32), human breast adenocarcinoma cells (MDA-MB-231), and human lung adenocarcinoma cells (A549) were selected as tested cancer lines, while cytotoxicity was investigated on normal human dermal fibroblasts (HFF-1). All the compounds were also tested against reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 and representatives of multidrug-resistant clinical isolates of methicillin-resistant S. aureus (MRSA) and vancomycin-resistant E. faecalis. Only the acetylene derivatives of 8-hydroxyquinoline-5-sulfonamide 3a–f were shown to be biologically active, and 8-hydroxy-N-methyl-N-(prop-2-yn-1-yl)quinoline-5-sulfonamide (3c) showed the highest activity against all three cancer lines and MRSA isolates. Its efficacies were comparable to those of cisplatin/doxorubicin and oxacillin/ciprofloxacin. In the non-cancer HFF-1 line, the compound showed no toxicity up to an IC50 of 100 µM. In additional tests, compound 3c decreased the expression of H3, increased the transcriptional activity of cell cycle regulators (P53 and P21 proteins), and altered the expression of BCL-2 and BAX genes in all cancer lines. The unsubstituted phenolic group at position 8 of the quinoline is the key structural fragment necessary for biological activity. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: We present a facile synthetic strategy to create mesoporous Cu2O nanocrystals with tunable pore structures and surface functional groups of amine derivatives for efficient and preferable electrochemical conversion of CO2 into ethylene. The structural characteristics of these Cu2O nanocrystals can be manipulated using a set of amine derivatives, such as pyridine, 4,4'‐bipyridine, and hexamethylenetetramine, during the oxidative etching process of Cu nanocrystals by bubbling gaseous oxygen in N,N‐dimethylformamide solution. These amine derivatives not only serve as surface functional groups but also significantly affect the resulting pore structures. The synergistic effect of pore structure confinement and surface amine functionalization leads to the superb Faradaic efficiency (FE) of 51.9% for C2H4, respectively, together with the C2H4 partial current density of –209.4 mA·cm−2 at –0.8 V vs. reversible hydrogen electrode (RHE). The relatively high selectivity towards C2H4 was investigated using DFT simulations, where 4,4'‐bipyridine functionalized Cu2O seemed to favor the C2H4 formation with the low free energy of the intermediates. This study provides a feasible strategy to manipulate the pore structure and surface functionalization of mesoporous Cu2O nanocrystals by regulating the oxidative etching process, which sheds light on the rational preparation of high‐performance CO2RR electrocatalysts. [ABSTRACT FROM AUTHOR]

An efficient method for N-arylation and N-N bond formation has been developed using an innoxious reaction medium, γ-valerolactone (GVL), as both a solvent and a ligand. The strategy involves utilizing CuI as a catalyst under conditions free of external ligands and bases. Various aldehyde and amine derivatives with different functional groups were investigated, resulting in the production of 2-aryl-2H-indazole compounds with yields ranging from 75% to 93%. This study highlights the effectiveness of GVL, a solvent derived from biomass, as a reaction medium and ligand in a multicomponent reaction. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) smart windows are an elegant alternative to dusty curtains, blinds, and traditional dimming devices. The EC energy storage smart windows and displays received remarkable attention in the optoelectronic industry as they hold promise for high energy efficiency, low power consumption, reversibility, and swift response to stimuli. However, achieving these properties remains challenging. Moreover, most EC molecules do not exhibit electrofluorochromism, which is highly essential for smart displays because its EC property can modulate the solar heat entering the building, and its electrofluorochromic (EFC) aspects can create lighting during the night. In this work, a structure‐property relationship is utilized to develop new electrochromes that can store the injected charge, and these molecules indeed exhibit electrofluorochromism. The compounds are synthesized from tetrabenzofluorene with two aromatic acceptor units, and avoids the use of widely studied heterocycles and amine derivatives. The electrochromes switches from yellow to dark hue in solution, solid, and gel state. The compounds display exceptional electrochemical stability and reversibility in 1000 cycles and capacity retention of 93–100 % in 300 charging‐discharging cycles. The proof‐of‐concept device fabrication of the self‐dimming EC smart window presented here demonstrates that it can furnish visual comfort, modulate transmitted light and glare, and reduce energy usage. [ABSTRACT FROM AUTHOR]

An efficient in situ condensation of citronellal, the main constituent of Eucalyptus citriodora essential oil (51%), with different amine derivatives of 2,3-diaminomaleonitrile and 3-[(2-aminoaryl)amino]dimedone has led to novel chiral benzodiazepine structures. All reactions were precipitated in ethanol and pure products were obtained in good yields (58–75%) without any purification. The synthesized benezodiazepines were characterized by spectroscopic techniques, namely 1H-NMR, 13C-NMR, 2D NMR and FTIR. Differential Scanning Calorimetry (DSC) and HPLC were used to confirm the formation diastereomeric mixtures of benzodiazepine derivatives. [ABSTRACT FROM AUTHOR]

This article presents a catalytic approach for site‐selective α‐C−H functionalization of N‐benzyl tetrahydroisoquinolines, which are important tertiary amine derivatives. Using iron salt as a catalyst, we have selectively functionalized carbon‐hydrogen bonds of tertiary amine molecules with diverse moieties, such as imidazopyridine, indoles, and phenylacetylenes. The method offers a broad substrate scope and excellent functional group tolerance, making it a valuable tool for the synthesis of complex molecules. A mechanism is also proposed based on control experiments, which explains the probable reason for selectivity. This iron‐catalyzed C−H functionalization represents a significant advancement in the field of organic synthesis, showcasing the potential of iron catalysis for the construction of valuable chemical motifs. [ABSTRACT FROM AUTHOR]

The three-component reaction of a diazo compound, azide and allylboronate was explored, and Rh2(esp)2 was utilized as the optimal catalyst. A series of α-amino esters were efficiently produced from the ethyl diazoacetate in 57–84% yields, and excellent diastereoselectivities were observed with the reaction employing (E)-allylboronate as the alkylation reagent. The α-amino ketone or homoallylic amine could also be prepared by using α-diazo ketone or trimethylsilyl diazomethane in acceptable yields. [ABSTRACT FROM AUTHOR]

Highly regioselective C−H alkylation reactions of tertiary anilines and tertiary alkyl amines with simple alkenes have been achieved by the use of imidazolin‐2‐iminato scandium alkyl complexes. This protocol provided an efficient and atom‐economical route to structurally diverse tertiary amine derivatives. The basic ligand, a coordinating THF in the catalyst and the substitution of alkene substrates were found to switch the regioselectivity of the C−H alkylation reactions of tertiary anilines presumably due to the generation of different types of catalytically active species or the formation of relatively stable intermediates. On the basis of the deuterium labeling experiments and KIE experiments, possible catalytical cycles were provided to understand the reaction mechanism as well as the regioselectivity. [ABSTRACT FROM AUTHOR]

Twelve novel camptothecin derivatives with a carbamate substituent at position 20 were designed and synthesized. Most of the targeted compounds indicated potent anti-inflammatory activity in a lipopolysaccharide stimulation of peritoneal macrophage model. Among them, the benzyl(methyl)amine derivative showed the most pronounced anti-inflammatory activity at a concentration of 1 μM and TNF-α inhibitory rate is increased by 10.2% compared to the lead compound (N,N-dimethylethylenediamine derivative). [ABSTRACT FROM AUTHOR]

Novel platinum(II) complexes of 4′-substituted terpyridine ligands were synthesized and characterized. Each complex had a different biomolecule (amine, glucose, biotin and hyaluronic acid) as a targeting motif, potentially improving therapeutic outcomes. We demonstrated that complexes can self-assemble in water into about 150 nm nanoparticles. Moreover, the complexes were assayed in vitro toward a panel of human cancer cell lines (ovarian adenocarcinoma A2780, lung cancer A549, breast adenocarcinoma MDA-MB-231, neuroblastoma SHSY5Y) to explore the impact of the pendant moiety on the terpyridine toxicity. The platinum complex of terpyridine amine derivative, [Pt(TpyNH2)Cl]Cl, showed the best antiproliferative effect, which was higher than cisplatin and [Pt(Tpy)Cl]Cl. Selective in vitro antiproliferative activity was achieved in A549 cancer cells with the Pt–HAtpy complex. These findings underline the potential of these novel platinum(II) complexes in cancer therapy and highlight the importance of tailored molecular design for achieving enhanced therapeutic effects. [ABSTRACT FROM AUTHOR]

The impressive photoluminescence properties of all inorganic cesium lead halide perovskite quantum dots (PeQDs) make them highly intriguing for fluorescence chemosensor applications. Herein, a ratiometric dual emitting perovskite-based sensor was designed by synthesizing fluorescent CsPbBr3 PeQDs in situ within a matrix of Eu-BDC (Eu(III) benzene-1,4-dicarboxylate). The results presented here establish the suggested sensor's quick and selective turn-on PL response to volatile primary aliphatic amine derivatives. In the presence of amines, the designed CsPbBr3/Eu-BDC sensor exhibits an enhancement of the PL signal of CsPbBr3 at 518 nm and the Eu-BDC signal at 615 nm served as a standard for constructing the ratiometric sensing system. Thereby, a visual color change from red to green was observed with the incremental addition of methylamine to the probe. A low detection limit of 0.083 ppm was determined for methylamine. In both the solution and vapor phases, this ratiometric sensor responds to a variety of primary aliphatic amines with very quick and strong fluorescence. Moreover, the sensor was effectively used for monitoring meat spoilage owing to the emission of biogenic amine vapor from meat products. [ABSTRACT FROM AUTHOR]

Herein, we demonstrated a visible light mediated tandem oxidation–organo catalyzed C−S bond functionalization protocol for the cleavage of aromatic C−S bond. The investigation encompassed the functionalization of C−S bonds within sulfones, sulfoxides, and aliphatic sulfide derivatives. However, the process of functionalizing the C−S bond in aromatic sulfides remains uncertain. The presented protocol demonstrates the C−S bond functionalization on benzo[b]benzo[4,5]thieno[2,3‐d]thiophene derivative and amines including primary and secondary amines as well. A radical mediated mechanism was proposed for the tandem oxidation–organocatalyzed C−S bond functionalization protocol. [ABSTRACT FROM AUTHOR]

The rapid assembly of valuable cyclic amine architectures in a single step from simple precursors has been recognized as an ideal platform in term of efficiency and sustainability. Although a vast number of studies regarding cyclic amine synthesis has been reported, new synthetic disconnection approaches are still high in demand. Herein, we report a catalytic radical‐polar crossover cycloaddition to cyclic amine synthesis triggered from primary sulfonamide under photoredox condition. This newly developed disconnection, comparable to established synthetic approaches, will allow to construct β, β‐disubstituted cyclic amine and β‐monosubstituted cyclic amine derivatives efficiently. This study highlights the unique utility of primary sulfonamide as a bifunctional reagent, which acts as a radical precursor and a nucleophile. The open‐shell methodology demonstrates broad tolerance to various functional groups, drug derivatives and natural products in an economically and sustainable fashion. [ABSTRACT FROM AUTHOR]

Complementary to the design of a single structurally complex chiral ligand to promote each step in transition‐metal catalysis, multiligand relay catalysis through dynamic ligand exchange with each step in the catalytic cycle promoted by its best ligand provides an attractive approach to enhance the whole reaction reactivity and selectivity. Herein, a regio‐ and enantioselective NiH‐catalyzed migratory hydroarylation process with a simple combination of a chain‐walking ligand and an asymmetric arylation ligand, producing high‐value chiral α‐(hetero)aryl‐substituted amines and their derivatives under mild conditions, is reported. The potential synthetic applications of this transformation are demonstrated by the concise synthesis of (S)‐nicotine and a CDK8 inhibitor. [ABSTRACT FROM AUTHOR]

Due to amine derivatives widely existing in numerous clinical medicines and bioactive compounds, their synthesis has received considerable attention over the past few decades. Traditional methods for the synthesis of amine derivatives largely relied on the reduction of nitroarenes, amides, hydrazines, nitriles, and azides. Recently, the discovery of 2‐azaallyl anions as super‐electron‐donors (SEDs) has opened up new possibilities for the construction of diverse carbon‐carbon and carbon‐heteroatom bonds through radical coupling strategies. This breakthrough highlights the potential of generating 2‐azaallyl radicals as versatile intermediates in organic synthesis. Then, hydrolysis of the coupling product can easily separate the corresponding amine derivatives. Thus, tremendous attention has been paid to the C−H functionalization of ketimines as an alternative strategy for the synthesis of amine derivatives. Herein, we comprehensively summarize the recent progress in radical coupling strategies enabled by 2‐azaallyl anions as SEDs. Their proposed mechanistic pathways, advantages, and limitations are also discussed in detail. 1. Introduction 2. C−C Bond Formation 2.1. Vinylation of Ketimines 2.2. Arylation of Ketimines 2.3. Alkylation of Ketimines 2.3.1. Methylation of Ketimines 2.3.2. Other Alkylation of Ketimines 3. C−X Bond Formation 3.1. C−P and C−S Bonds Formation 3.2. C−N and C−O Bonds Formation 4. Conclusions [ABSTRACT FROM AUTHOR]

A new efficient approach to the synthesis of intensely colored 2‐(2‐oxo‐3H‐pyrrol‐3‐ylidene)malononitrile (OP) was developed. Using the reaction of OP with amines, a series of previously unknown colorless organic salts – dicyano(2‐oxo‐2,5‐dihydro‐1H‐pyrrol‐3‐yl)methanides were synthesized, bearing in the structure two fragments of same or diverse amines of different nature (covalent and ionic). TGA‐DTA study of the synthesized salts showed a thermal reversibility of their formation. The introduction of violet OP into paper followed by treatment with amine vapors revealed prospects of using such a system for naked‐eye detection of volatile amines. It was also shown that OP‐based rewritable paper can be created, to which a data can be applied by local heating and erased by the action of amine or temperature. [ABSTRACT FROM AUTHOR]

Three novel mononuclear 4‐vinylpyridine‐based Fe(III) complexes [FeL(4‐VP)]BPh4 (4‐VP=4‐vinylpyridine; H2L=bis(salicylicdeneaminopropyl)amine, H2salten, 1; H2L=bis(salicylicdeneaminopropyl)methylamine, H2saltenMe, 2; H2L=bis(3‐methoxysalicylideneaminopropyl)methylamine, 3‐OMeH2saltenMe, 3) were synthesized and characterized. Single‐crystal X‐ray diffraction analyses revealed that 1–3 both present the mononuclear structure based on 4‐VP coordinated with bis(salicylicdeneaminopropyl)amine and its derivatives, which give 2D architectures by various interactions among cations and counter‐ions. Magnetic studies showed that both 1 and 2 exhibit one‐step complete spin‐crossover (SCO) behaviours with critical transition temperatures (T1/2) of 178 and 87 K respectively, while 3 exhibits one‐step incomplete spin crossover behaviour (T1/2,3=93 K). The introduction of methyl groups on the amine nitrogen of the Schiff base ligands in 2 and 3 give the bigger repulsive effect, further decrease the cooperation of spin centres, resulting in their spin transition occurring at lower temperatures. In addition, the presence of C−H⋯O weak interactions in 1 and 3 with synergistic effect, led to their spin transition temperatures being higher than that of 2. [ABSTRACT FROM AUTHOR]

This paper presents a amidinyl transfer reagent for the synthesis of nitrogen‐containing compounds, wherein N,N‐dimethylformamide is used as the C1 source to react with hexamethyldisilazane, generating the N,N‐dimethylformimidamide intermediate. This intermediate is then reacted with amines to induce amidinyl transfer. This protocol can be applied for the synthesis of N‐formamide, benzimidazole and quinazolinone, for which amine derivatives used as substrates under optimized conditions. The advantages of this method are its operational simplicity, high efficiency, structural diversity in products with favorable yields, and applicability in gram‐scale operations. [ABSTRACT FROM AUTHOR]

A new bioactive amine and amide derivatives of trifluoromethyl pyridine was produced with good yields from commercially accessible and inexpensive starting materials and characterized using 1HNMR, 13CNMR, and mass spectrum analysis. We prepared all the intermediates in gram scale, it will be viable for industrial production, because the compounds contain a bioactive core component, trifluoromethylpyridine, they will be useful in developing new insecticides with improved therapeutic action. [ABSTRACT FROM AUTHOR]

This document provides information on the synthesis and characterization of pyrido[2,3-b]quinoxaline-3-carboxylate derivatives through a one-pot Buchwald amination-cyclization method. The derivatives have potential pharmacological activities, including antibacterial, antiviral, anticancer, and antifungal properties. The study successfully achieved good yields using specific reaction conditions and explored the synthesis of these derivatives with different amines. The document includes detailed procedures, characterization data, physical properties, and spectroscopic data for specific derivatives. The research was supported by various institutions and funding sources. [Extracted from the article]

To extract vanadium (V) ions from the ferruginous siltstone at Abu Zeneima in Southwestern Sinai, Egypt, a synthesized chelating N-phenyl acetyl-N-naphthyl hydroxyl amine (PANHA), was used. Complete characterization was carried out successfully to elucidate the structure using several techniques such as FT-IR,1H-NMR, 13C-NMR, GC-MS and TGA analysis performances. Improved experimental measurements, such as pH, shaking time, initial concentration of V(V), PANHA dosage, temp., and stripping agents, have been achieved with the solvent extraction technique. At 25 ℃ and 0.015 mole per liter through 30 minutes, PANHA/CHCl3 has an extreme retention potential of 50 mg per gram at 25 ℃ at pH 1.5 at 1:1 aqueous to organic phase ratio. The linear regression analysis, consisting of a log D track versus pH, shows a straight line with a slope of 0.859, indicates that a mole of H+ was released during the extraction. The stability constant (β), of PANHA-V(V) complex was calculated from the intersection (log β=1.7958), and it was found to equal 63.1. The stoichiometry mechanism among a chelating ligand of PANHA and V(V) indicates a roughly linear correlation with slope of 0.882 which explains that one mole of PANHA chelating ligand can react with one mole of V (V). According to the kinetic and thermodynamic interpretations, the pseudo-second order kinetic model predicted the kinetics of vanadium (V) extraction, the thermodynamic factors ΔS, ΔH, and ΔG were also measured. As the temperature rises, ∆G values rise from -10.45 kJ/mol at 198 K to -2.2 kJ/mol at 353 K. Vanadium may be stripped from the loaded PANHA/CHCl3, by 0.5M NaOH with a 99% efficiency rate. To obtain a vanadium concentrate (NH4VO3, AMV) with a vanadium content of 42.6 percent and pureness of 98 percent, the enhanced variables were finally put to use. [ABSTRACT FROM AUTHOR]

A series of six new donor‐acceptor (D−A) type 2,3‐di(pyridin‐2‐yl)pyrido[2,3‐b]pyrazine amine derivatives as blue‐orange light emitting materials were designed, synthesized, characterized and their relevant opto‐electrochemical and theoretical properties have been fully investigated. Absorption spectra of dyes 2–7 possess intramolecular charge transfer (ICT) transitions (λmax=394–449 nm) and positive solvatochromism with emission in the blue‐orange region (λemm=477–582 nm) in solution and solid state. Further, the HOMO (−5.32 to −5.86 eV) and LUMO (−3.34 to −3.40 eV) energy levels were calculated by cyclic voltammetry (CV) and correlated by DFT/TD−DFT calculations. Moreover, computed singlet (S1) and triplet (T1) excitation energy difference (ΔEST=0.27–0.68 eV) were analyzed using the DFT/TD−DFT methods. Thus, potential applications of the dyes are proposed for organic electronics. [ABSTRACT FROM AUTHOR]

Over the past twenty years (1998–2023), extensive research has focused on the synthesis and biological activity of Mannich base derivatives of flavonoids (FMBD), which have demonstrated exceptional properties towards organic and bioorganic molecules. Several research groups have reported the pharmacological potential of these flavonoid derivatives, including antioxidant and antiviral activities, as well as their ability to inhibit AChE and exhibit anticancer properties. Moreover, the unique characteristic of forming stable complexes with biomolecules positions flavonoid derivatives as valuable assets in the realm of biology and drug discovery. In this extensive review, we′ve meticulously analyzed over seventy six distinct research studies on this subject. Our aim is to provide a succinct overview of the wide‐ranging applications of flavonoid derivatives coupled with amines. Furthermore, we explore the promising horizons and potential innovations in this field. It's essential to highlight that these derivatives display no discernible signs of toxicity or eliciting immune responses, making them even more attractive for biopharmaceutical applications. Undoubtedly, the utilization of flavonoid derivatives combined with amines as crucial biopharmaceutical agents is poised for significant expansion in the forthcoming years. [ABSTRACT FROM AUTHOR]

The Chan–Lam reaction conditions were optimized for the synthesis of N-aryl derivatives of adamantane-containing amines. A number of adamantane-containing amines and diamines with different steric hindrances at the primary amino groups were reacted with p-tolylboronic acid under the optimized conditions [0.1 M solution of amine in MeCN, p-tolylboronic acid (2 equiv), DBU (2 equiv), copper(II) acetate (20 mol %), 25°C, 24 h]. The reactivity of the amines was found to strongly depend on their structure, and the maximum yield of the target products reached 74% from the monoamines and 66% from the diamines. [ABSTRACT FROM AUTHOR]

A new family of triaminocyclopentadienyl iron(II) tricarbonyl complexes has been synthesized, fully characterized and applied in hydrogenation transfer. These complexes are the first Earth‐abundant metal complexes able to catalyze reductive alkylation of primary and secondary aliphatic amines with 2‐diarylphosphinobenzaldehyde derivatives at room temperature. These non‐pincer type cyclopentadienyl iron(II) complexes demonstrate not only better efficiency than known cyclopentadienone iron carbonyl complexes but also high functionality tolerance. The resulting aminophosphines provide a straightforward and rapid access to potential P−N ligands. [ABSTRACT FROM AUTHOR]

(+)-Neomenthylamine is an important industrial precursor used to synthesize high value-added chemicals. Here, we report a novel biocatalytic route to synthesize (+)-neomenthylamine by amination of readily available (−)-menthone substrate using ω-transaminase. By screening a panel of ω-transaminases, an ω-transaminase from Vibrio fluvialis JS17 was identified with considerable amination activity to (−)-menthone, and then characterization of enzymatic properties was conducted for the enzyme. Under optimized conditions, 10 mM (−)-menthone was transformed in a mild aqueous phase with 4.7 mM product yielded in 24 h. The biocatalytic route using inexpensive starting materials (ketone substrate and amino donor) and mild reaction conditions represents an easy and green approach for (+)-neomenthylamine synthesis. This method underscores the potential of biocatalysts in the synthesis of unnatural terpenoid amine derivatives. [ABSTRACT FROM AUTHOR]

An operationally convenient and efficient one-pot reductive amination of diversely substituted aldehydes catalyzed by Fe3O4@TiO2 nanoparticles and NaBH4 as a reductant in ethanol at ambient condition is reported in this work. The structural features of Fe3O4@TiO2 nanoparticles are explored by various tools like FT-IR, XRD, TEM, FE-SEM and EDX techniques. The heterogeneous nature, good catalytic potential and reusability are some of the important attributes of the catalyst. The beneficial features of this procedure are one-pot reaction, short reaction time, low catalyst requirement, applicability to wide range of substrates with good yields, milder and simple reaction condition. The structures of synthesized amine derivatives were established by 1H-NMR, 13C-NMR and HR-MS spectral analysis. [ABSTRACT FROM AUTHOR]

N-(Het)arylation of adamantane-containing amines with halonaphthalenes and haloquinolines catalyzed by either CuI or copper nanoparticles with an average size of 25 nm in the presence of 2-isobutyrylcyclohexanone, rac-BINOL, and l-proline as a ligand and Cs2CO3 as a base in DMSO at 110 °C was studied. The reactions proceed smoothly with 2-iodonaphthalene and 6-iodoquinoline, the possibility of successful reactions with 6- and 3-bromoquinolines was also shown. In the case of 1-bromonaphthalene, 5- and 8-bromoquinolines, only Pd-catalyzed amination can provide the high yields of the products. An alternative possibility of C(sp2)—N bond formation was studied employing the Chan—Lam reaction with of 2-naphthaleneboronic acid and pinacolates of 6- and 3-quinolineboronic acids. [ABSTRACT FROM AUTHOR]

This review is intended to elucidate the structure, biological activity, and use of various strategies for the synthesis of terphenyl and its derivatives from amines obtained by the Stevens rearrangement. The amine transformation is a domino reaction, including β-elimination of secondary amine with the formation of a conjugated dienyne, which forms a cyclic allene intermediate by an electrocyclic reaction. The subsequent 1,3- or 1,5-hydride shift rapidly produces the final compound. [ABSTRACT FROM AUTHOR]

Some furan/thiophene-2-carboxamide derivatives (1–3) were prepared from acyl chlorides and heterocyclic amine derivatives with good yields, employing synthetic route and their chemical structures were confirmed using different spectroscopic methods including IR, 1H NMR, 13C NMR and elemental analysis. Three different enzyme inhibition effect tests as urease, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibiting activities, were applied to these compounds. The biological evaluation results clearly showed that the compound 1 showed approximately 9.8-fold more activity against urease enzyme than thiourea standard while the compound 3 showed approximately 4.2-fold more activity against BChE enzyme than galantamine standard. The molecular interaction for each of the target compounds with the active sites of the urease, acetylcholinesterase and butyrylcholinesterase enzymes was investigated by molecular insertion simulations and the results were confirmed the experimental findings. The results also show that compounds such as 1 and 3 carrying thiophene/furan carbocamide moieties could be used promising structures in the development of more potent pharmaceutical agents in the future. [ABSTRACT FROM AUTHOR]

Compounds with a 3-oxabicyclo[3.3.1]nonane core were prepared from limonene and aromatic aldehydes containing methoxy groups and phthalaldehydes in the presence of montmorillonite K10 and were converted to aromatic amines containing this heterocycle. Some of the products were found to exhibit inhibitory activity in the reaction catalyzed by human tyrosyl-DNA phosphodiesterase 1 in the micromolar range. Bromo derivatives of amines, compounds 6b and 7b, which combine high inhibitory activity and low cytotoxicity, are promising for further studies in order to create new agents for the use in combined anticancer therapy. [ABSTRACT FROM AUTHOR]

Large‐area continuous covalent organic frameworks (COFs) film is highly desirable for the large‐scale continuous selective photocatalytic coupling of benzylamine (BA); however, traditional synthetic methods for preparing COFs films still suffer from the issues of harsh reaction condition, film breakage, and high energy‐consumption. Herein, a room‐temperature strategy is reported for making large‐area continuous imine‐based COFs film through the "infiltration‐reaction‐assembly" mechanism, demonstrating that such strategy is quite universal for making four types of large‐area COFs films. The as‐made PyTTA‐TPA (PyTTA: 1，3，6，8‐tetrakis(4‐aminophenyl)pyrene, TPA: p‐benzaldehyde) COFs film exhibits excellent catalytic performance for selective photocatalytic coupling of benzylamine (BA) with a high conversion rate of 98.2% and high selectivity of 97% in 3 h, which is the best photocatalytic performance in all reported photocatalysts. In addition, the as‐made COFs film is quite general for achieving photocatalytic coupling of other amine derivatives with outstanding photocatalytic performance of ≈100% conversion rate. Overall, this work brings a significant development for the room‐temperature synthesis of large‐area continuous COFs film to photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Imidazo[1,2-a]pyrimidine derivatives bearing imine groups (3a-e) were successfully synthesized in moderate to good yields using microwave-assisted heating. Corresponding amine derivatives (4a-e) were also obtained by the reduction reaction of the imine derivatives (3a-e). All synthesized products were characterized by FT-IR, ¹H NMR, 13C NMR, and LC-MS spectroscopic techniques. In silico ADMET, Lipinski, and drug-likeness studies of the compounds were conducted and all were found to be suitable drug candidates. The cytotoxicity of the potential drug molecules was screened against the breast cancer cell lines MCF-7 and MDA-MB-231 and the healthy model HUVEC by the sulforhodamine B method. According to the antiproliferative studies, compounds 3d and 4d showed remarkable inhibition of MCF-7 cells with IC50 values of 43.4 and 39.0 μM and of MDA-MB-231 cells with IC50 values of 35.9 and 35.1 μM, respectively. In particular, compound 3d selectively inhibited the proliferation of MCF-7 1.6-fold and MDA-MB-231 2.0-fold relative to healthy cells. Moreover, the apoptotic mechanism studies indicated that compound 4d induced apoptosis by moderately increasing the ratio of Bax/Bcl-2 genes. Imidazo[1,2-a]pyrimidine derivative 3d, a promising cytotoxic agent, may be helpful in the discovery of new and more efficient anticancer agents for breast cancer treatment. [ABSTRACT FROM AUTHOR]

Glycyrrhizic acid (GL) is the main active ingredient of licorice, which is widely used as a traditional medicine in many countries, especially in the East Asia region (China, Japan). Many studies have shown that GL has a wide range of anti-inflammatory and antiviral effects. The GA aglycone and the glucuronate fraction of its structure play an important role in the design of derivatives with the target molecules during the activation process. In the present study, the amine derivatives of GL were designed and synthesized as promising derivatives with high efficacy and important physicochemical properties. GL was treated with HCl-CH3OH solution to obtain dimethyl glycyrrhizate. In the activation process, the carboxyl groups in glucuronic acid exhibited higher reactivity than those in C30. Second, in the presence of coupling agents HOBt/EDCI and organic bases, GL reacted with various amino acids in solvents such as DMF or dioxane to obtain seven glycyrrhizate diamide derivatives, which were characterized by IR and 1H NMR spectra. [ABSTRACT FROM AUTHOR]

A novel and eco‐friendly technique for the synthesis of C‐3 nitro derivatives of 4‐quinolones via the regioselective C(sp2)−H bond functionalization employing tert‐butyl nitrite as nitrating agent in presence of TEMPO [(2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl] as an oxidant is unfolded herein. The protocol is scalable as well as high yielding with wide substrate scope and broad functional group tolerance. In‐depth mechanistic investigations revealed that the reaction occurred through a free radical pathway. The nitro derivatives of 4‐quinlones were selectively reduced to corresponding aminated 4‐quinolones. Finally, the photophysical properties of synthesized amine derivatives were also investigated, and some of them showed good fluorescence properties. [ABSTRACT FROM AUTHOR]

Benzylic amine derivatives are ubiquitous structural motifs in organic chemistry. Herein we report a direct synthesis of these compounds via a direct desulfonylative C-arylation of O-tosyl hydroxamates. The applicability of this Ru-catalyzed aminoalkylation is being exemplified by a set of late-stage functionalizations of natural products. [ABSTRACT FROM AUTHOR]

A photoredox‐mediated radical amidation ring‐expansion sequence that enables the generation of all‐carbon quaternary centers bearing a protected aminomethyl substituent is described. The methodology can be applied to both styrene and unactivated alkene substrates generating structurally diverse sp3‐rich amine derivatives in a concise manner. [ABSTRACT FROM AUTHOR]

Heterometallic FeCo dinuclear complexes on the basis of the redox-active 1,10-phenanthroline-5,6-dione with ancillary bis(pyrazolyl)borate anions and tetradentate N-donor ligands (N,N′-dialkyl-2,11-diaza[3.3]-(2,6)pyridinophane and tris(2-pyridilmethyl)amine derivatives) were studied by the DFT UTPSSh/6–311 + + G(d,p) method in a view to possible spin-crossover (SCO) or valence tautomeric (VT) interconversions. The electronic structures (namely, spin and oxidation states of the electronically labile centers) and magnetic properties of the considered compounds were found to be determined by the position of the outer-sphere PF6– counterion and the type of N-donor base. The most energetically preferred isomers contain a counterion near the cobalt ion. The presence of PF6– next to the iron center stabilizes the ferric state of this metal and the dianionic form of the 1,10-phenanthroline-5,6-dione linker ligand. The variation of the structural peculiarities allowed us revealing the dinuclear complexes prone to exhibit the SCO and VT processes, which makes them promising building blocks of magnetic materials. [ABSTRACT FROM AUTHOR]

Some aromatic amines (AA) have been classified as carcinogens to humans. After entering the body, mainly through tobacco smoke, they can be detected in urine. Thus, their trace analysis as biomarkers in biofluids is of high relevance and can be achieved with gas chromatography (GC–MS), usually after derivatization. This study compares three gas chromatographic methods for the analysis of ten iodinated derivatives of AA: GC–MS in single-ion monitoring (SIM) mode with (1) electron ionization (GC-EI-MS) and (2) negative chemical ionization (GC-NCI-MS), and (3) GC-EI-MS/MS in multiple reaction monitoring (MRM) mode using electron ionization. All methods and most analytes showed good coefficients of determination (R2 > 0.99) for broad linear ranges covering three to five orders of magnitude in the picogram-per-liter to nanogram-per-liter range, with one and two exceptions for (1) and (2) respectively. Excellent limits of detection (LODs) of 9–50, 3.0–7.3, and 0.9–3.9 pg/L were observed for (1), (2), and (3) respectively, and good precision was achieved (intra-day repeatability < 15% and inter-day repeatability < 20% for most techniques and concentration levels). On average, recoveries between 80 and 104% were observed for all techniques. Urine samples of smokers and non-smokers were successfully analyzed, and p-toluidine and 2-chloroaniline could be found at significantly (α = 0.05) higher concentrations among smokers. [ABSTRACT FROM AUTHOR]

Rice bacterial leaf blight is a destructive bacterial disease caused by Xanthomonas oryzae pv. oryzae (Xoo) that seriously threatens crop yields and their associated economic benefits. In this study, a series of improved dissolubility 7-aliphatic amine tryptanthrin derivatives was designed and synthesized, and their potency in antibacterial applications was investigated. Notably, compound 6e exhibited excellent activity against Xoo, with an EC50 value of 2.55 μg/mL, compared with the positive control bismerthiazol (EC50 = 35.0 μg/mL) and thiodiazole copper (EC50 = 79.4 μg/mL). In vivo assays demonstrated that 6e exhibited a significant protective effect on rice leaves. After exposure, the morphology of the bacteria was partially atrophied by SEM. Furthermore, 6e increased the accumulation of intracellular reactive oxygen species, causing cell apoptosis and the formation of bacterial biofilms. All the results indicated that 6e could be a potential agrochemical bactericide for controlling phytopathogenic bacteria. [ABSTRACT FROM AUTHOR]

Proprotein convertase subtilisin/kexin type 9 (PCSK9) has emerged as a promising therapeutic target for the treatment of hyperlipidemia. In discovery of novel small molecules that interfere PCSK9/LDLR protein–protein interaction (PPI), structural modification was performed based on our previously derived compounds. A series of [5,5′‐bibenzo[d][1,3]dioxol]‐6‐amine analogs were designed and synthesized for the activity evaluation. In the PCSK9/LDLR PPI impairing test, molecules D28 and D29, exhibited remarkable inhibitory potency with IC50 values of 8.30 and 6.70 μM compared with SBC‐115337 (17.89 μM), respectively. Molecular docking predicted the binding pattern of compounds D28 and D29 in the LDLR binding site of PCSK9. Hydrophobic interactions play an important role in the binding of aromatic molecular fragments to the pockets in the PCSK9/LDLR binding interface. Further LDLR expression and LDL uptake studies revealed that both D28 and D29 restored LDLR expression on the surface of hepatic HepG2 cells and improved extracellular LDL uptake in the presence of PCSK9. It is significant that molecules D28 and D29 exhibited potential for the treatment of hyperlipidemia in current in vitro investigations. Generally, lead compounds with novel structures were developed in the present study for further design of lipid‐lowering molecules by targeting PCSK9/LDLR PPI. [ABSTRACT FROM AUTHOR]

A protonated and hydrated Dion-Jacobson-phase HSr2Nb3O10∙yH2O was used to prepare two series of inorganic–organic derivatives containing non-covalently intercalated n-alkylamines and covalently grafted n-alkoxy groups of different lengths, as they are promising hybrid materials for photocatalytic applications. Preparation of the derivatives was carried out both under the conditions of standard laboratory synthesis and by solvothermal methods. For all the hybrid compounds synthesized structure, quantitative composition, a type of bonding between inorganic and organic parts as well as light absorption range were discussed using powder XRD, Raman, IR and NMR spectroscopy, TG, elemental CHN analysis, and DRS. It was shown that the inorganic–organic samples obtained contain approximately one interlayer organic molecule or group per proton of the initial niobate, as well as some amount of intercalated water. In addition, the thermal stability of the hybrid compounds strongly depends on the nature of the organic component anchoring to the niobate matrix. Although non-covalent amine derivatives are stable only at low temperatures, covalent alkoxy ones can withstand heat up to 250 °C without perceptible decomposition. The fundamental absorption edge of both the initial niobate and the products of its organic modification lies in the near-ultraviolet region (370–385 nm). [ABSTRACT FROM AUTHOR]

Medium polarity plays a crucial role in charge-transfer processes and electrochemistry. The added supporting electrolyte in electrochemical setups, essential for attaining the needed electrical conductivity, sets challenges for estimating medium polarity. Herein, we resort to Lippert–Mataga–Ooshika (LMO) formalism for estimating the Onsager polarity of electrolyte organic solutions pertinent to electrochemical analysis. An amine derivative of 1,8-naphthalimide proves to be an appropriate photoprobe for LMO analysis. An increase in electrolyte concentration enhances the polarity of the solutions. This effect becomes especially pronounced for low-polarity solvents. Adding 100 mM tetrabutylammonium hexafluorophosphate to chloroform results in solution polarity exceeding that of neat dichloromethane and 1,2-dichloroethane. Conversely, the observed polarity enhancement that emerges upon the same electrolyte addition to solvents such as acetonitrile and N,N-dimethylformamide is hardly as dramatic. Measured refractive indices provide a means for converting Onsager to Born polarity, which is essential for analyzing medium effects on electrochemical trends. This study demonstrates a robust optical means, encompassing steady-state spectroscopy and refractometry, for characterizing solution properties important for charge-transfer science and electrochemistry. [ABSTRACT FROM AUTHOR]

Background: Most frequently the functionalization of nanoparticles is hampered by time-consuming, sometimes harsh conjugation and purification procedures causing premature drug release and/or degradation. A strategy to circumvent multi-step protocols is to synthesize building blocks with different functionalities and to use mixtures thereof for nanoparticle preparation in one step. Methods: BrijS20 was converted into an amine derivative via a carbamate linkage. The Brij-amine readily reacts with pre-activated carboxyl-containing ligands such as folic acid. The structures of the building blocks were confirmed by different spectroscopic methods and their utility was assessed by one-step preparation and characterization of nanoparticles applying PLGA as a matrix polymer. Results: Nanoparticles were about 200 nm in diameter independent of the composition. Experiments with human folate expressing single cells and monolayer revealed that the nanoparticle building block Brij mediates a "stealth" effect and the Brij-amine-folate a "targeting" effect. As compared to plain nanoparticles, the stealth effect decreased the cell interaction by 13%, but the targeting effect increased the cell interaction by 45% in the monolayer. Moreover, the targeting ligand density and thus the cell association of the nanoparticles is easily fine-tuned by selection of the initial ratio of the building blocks. Conclusions: This strategy might be a first step towards the one-step preparation of nanoparticles with tailored functionalities. Relying on a non-ionic surfactant is a versatile approach as it might be extended to other hydrophobic matrix polymers and promising targeting ligands from the biotech pipeline. [ABSTRACT FROM AUTHOR]

The aim of the study was a synthesis and investigation of the dose-dependent anti-inflammatory effect of new thiourea derivatives of naproxen with selected aromatic amines and esters of aromatic amino acids. The results of the in vivo study indicate that derivatives of m-anisidine (4) and N-methyl tryptophan methyl ester (7) showed the most potent anti-inflammatory activity four hours after injection of carrageenan, with the percentage of inhibition of 54.01% and 54.12%, respectively. In vitro assays of COX-2 inhibition demonstrated that none of the tested compounds achieved 50% inhibition at concentrations lower than 100 µM. On the other hand, the aromatic amine derivatives (1–5) accomplished significant inhibition of 5-LOX, and the lowest IC50 value was observed for compound 4 (0.30 μM). High anti-edematous activity of compound 4 in the rat paw edema model, together with potent inhibition of 5-LOX, highlight this compound as a promising anti-inflammatory agent. [ABSTRACT FROM AUTHOR]

Reductive amination is a valuable method for amine synthesis that has been the topic of a century's worth of in‐depth study in both academia and industry. Amines and their derivatives serve as incredibly adaptable building blocks for a broad array of organic substrates and are significant precursors for a myriad of advanced chemicals, physiologically active compounds, agrochemicals, biomolecules, pharmaceuticals, and polymers. The creation of innovative catalytic processes for the long‐term and selective synthesis of amines from readily accessible and environmentally benign reagents remains a top priority in chemical research. Both heterogeneous and homogeneous catalysts have been designed with success to enable these reactions to explore new amines. Ruthenium catalysts are employed in reductive amination owing to their stability, selectivity, versatility, low toxicity, and high efficiency. This review comprehensively overviews the Ru‐catalyzed reductive amination processes and includes the literature from 2009 to 2022. [ABSTRACT FROM AUTHOR]

Nintedanib, a potent, oral, small‐molecule tyrosine kinase inhibitor, is known as a triple angiokinase inhibitor, inhibiting three major signaling pathways in angiogenesis. Here, we report full details of the alternative path toward the synthesis of nintedanib via novel intermediates. A key feature of our approach is the stereoselective intramolecular cyclization strategy that enables the concise conversion of β‐keto amide into a 3‐acyloxindole derivative, which is an important scaffold for nintedanib synthesis. Subsequent condensation of oxindole scaffold with synthesized amine derivative led to the drug nintedanib with good yields. [ABSTRACT FROM AUTHOR]