Synthesis Of N-alkyl Research Articles

A new synthesis of indolo[2,3-b]quinolines from 3-acetyl-N-alkyl-2-chloroindoles with 2-aminobenzophenone.

A new synthesis of N-alkyl- and 11-phenyl-modified indolo[2,3-b]quinolines was achieved via PEG-400-promoted and visible light-induced one-step reaction of 3-acetyl-N-alkyl-2-chloroindoles with 2-aminobenzophenone in 40% methanol aqueous solution. The merits of the protocol include cost efficiency, convenience, and eco- and user-friendliness.

Synthesis of N-alkyl- and N-alkenyl-substituted polyanilines. Properties and antibacterial activity study

Synthesis of N-alkyl- and N-alkenyl-substituted polyanilines. Properties and antibacterial activity study

Synthetic preparation of N-alkyl and N-aryl arenesulfinamides using an arenesulfinic acid-CDI driven approach

A new synthetic methodology has been developed for the synthesis of N-alkyl and N-aryl arenesulfinamides. The methodology involved reacting arenesulfinic acids (R = -Me, -H, -Cl) with 1,1’-carbonyldiimidazole (CDI) to form the reactive intermediate, an arenesulfinylimidazole. This intermediate was then reacted with both primary and secondary amines to yield the corresponding N-alkyl sulfinamides in yields up to 90%. While the overall yields ranged from 52% to 90%, the level of diastereoselection with racemic or enantiomerically enriched amines only reached a level of 54:46 favoring the major diastereomer as determined by analysis of the 500 MHz 1H NMR spectra. A series of aniline derivatives were also investigated as coupling partners and were found to form the N-aryl arenesulfinamide in good yield.

A Convenient Access to Functionalized Oxazol-2-One-5-Carboxylates from β-Aminoalcohols Through NBS-Light Mediated Oxidation of Cis- or Trans-N-Alkyloxazolidinones

An efficient methodology is developed involving a metal-free oxidation of cis or trans-trisubstituted oxazolidin-2-ones in the presence of NBS under light irradiation for the synthesis of N-alkyl oxazol-2-one-5-carboxylates. The mild conditions employed enable the efficient and rapid synthesis of a variety of those compounds in satisfactory yields.

Design and Synthesis of Lactams Derived from Mucochloric and Mucobromic Acids as Pseudomonas aeruginosa Quorum Sensing Inhibitors.

Bacterial infections, particularly hospital-acquired infections caused by Pseudomonas aeruginosa, have become a global threat with a high mortality rate. Gram-negative bacteria including P. aeruginosa employ N-acyl homoserine lactones (AHLs) as chemical signals to regulate the expression of pathogenic phenotypes through a mechanism called quorum sensing (QS). Recently, strategies targeting bacterial behaviour or QS have received great attention due to their ability to disarm rather than kill pathogenic bacteria, which lowers the evolutionary burden on bacteria and the risk of resistance development. In the present study, we report the design and synthesis of N-alkyl- and N-aryl 3,4 dichloro- and 3,4-dibromopyrrole-2-one derivatives through the reductive amination of mucochloric and mucobromic acid with aliphatic and aromatic amines. The quorum sensing inhibition (QSI) activity of the synthesized compounds was determined against a P. aeruginosa MH602 reporter strain. The phenolic compounds exhibited the best activity with 80% and 75% QSI at 250 µM and were comparable in activity to the positive control compound Fu-30. Computational docking studies performed using the LasR receptor protein of P. aeruginosa suggested the importance of hydrogen bonding and hydrophobic interactions for QSI.

Synthesis of pyrroles via ruthenium-catalyzed nitrogen-transfer [2\u2009+\u20092\u2009+\u20091] cycloaddition of \u03b1,\u03c9-diynes using sulfoximines as nitrene surrogates

Pyrrole is a privileged five-membered aromatic nitrogen heterocycle, which is ubiquitous in natural products, drug molecules, and functional materials. Therefore, numerous synthetic routes to substituted pyrroles have been extensively developed. Nevertheless, the efficient and short-step synthesis of highly substituted and/or fused pyrroles has remained a significant challenge in organic chemistry. Here we report a ruthenium-catalyzed nitrogen-transfer [2 + 2 + 1] cycloaddition of α,ω-diynes involving cyclic biscarbenoid intermediates. To achieve the key nitrogen transfer to carbenoid carbons, sulfoximines are employed as nitrene surrogates. Consequently, diverse fused pyrroles are successfully synthesized in good yields with wide functional group compatibility. Moreover, this method allows the synthesis of N-alkyl, N-aryl, and even N-H pyrroles, which are difficult to obtain using previous [2 + 2 + 1]-type reactions. Nitrogen transfer from sulfoximines to cyclic biscarbenoid intermediates is supported by density functional theory calculations and control experiments.

Simple and efficient synthesis of N-alkyl and N-aryl succinimides in hot water

ABSTRACTA new, simple synthesis of succinimides is described. The reactions were carried out under the ultimate green conditions excluding both catalyst and organic solvent by applying simple stirring at 100 °C. A wide variety of N-susbstituted succinimides have been prepared in high yields by using succinic acid and primary amines in hot water. Yield of N-alkyl substituted succinimides were found to be higher than those of N-aryl substituted succinimides.

Synthesis of N-alkyl (aril)-tetra pyrimidine thiones and investigation of their human carbonic anhydrase I and II inhibitory effects

Tetrahydropyrimidine thiones, which are cyclic thiocarbamides derivatives, were synthesised from thiourea, β-diketones and substituted benzaldehydes. A tautomeric form of these derivatives incorporates the thiol functionality, which is known to interact with metal ions from metalloenzymes active sites, such as the carbonic anhydrases (CAs, EC 4.2.1.1) among others. This is a superfamily of widespread enzymes, which catalyses a crucial biochemical reaction, the reversible hydration of carbon dioxide to bicarbonate and protons (H+). The newly synthesised N-alkyl (aril)-tetrahydropyrimidine thiones were tested for inhibition of the cytosolic human isoforms I and II (hCA I and II). Both isoforms were effectively inhibited by the newly synthesised thiones. Ki values were in the range of 218.5 ± 23.9–261.0 ± 41.5 pM for hCA I, and of 181.8 ± 41.9–273.6 ± 41.4 pM for hCA II, respectively. This under-investigated class of derivatives may bring interesting insights in the field of non-sulphonamide CA inhibitors.

Iron-catalyzed C–N bond formation via oxidative Csp3–H bond functionalization adjacent to nitrogen in amides and anilines: Synthesis of N-alkyl and N-benzyl azoles

Iron catalyzed oxidative protocol was developed to couple azoles with amides to generate N-alkylazole derivatives in moderate to excellent yields using tertiarybutyl hydroperoxide as an oxidant under mild reaction conditions. Furthermore, this protocol explored to couple azoles with N-alkylanilines, unexpectedly N-benzyl azoles were obtained as major products under these oxidative conditions.

N-Alkyl derivatives of diosgenyl 2-amino-2-deoxy-β-D-glucopyranoside; synthesis and antimicrobial activity.

Diosgenyl 2-amino-2-deoxy-β-D-glucopyranoside is a synthetic saponin exhibiting attractive pharmacological properties. Different pathways tested by us to obtain this glycoside are summarized here. Moreover, the synthesis of N-alkyl and N,N-dialkyl derivatives of the glucopyranoside is presented. Evaluation of antibacterial and antifungal activities of these derivatives indicates that they have no inhibitory activity against Gram-negative bacteria, whereas many of the tested N-alkyl saponins were found to inhibit the growth of Gram-positive bacteria and human pathogenic fungi.

Facile and Simple Synthesis of N-Alkyl and N-Aryl 2-Benzazepines by Nucleophilic Heteroannulation

An efficient and practical synthesis of N-alkyl and N-aryl 2-benzazepine has been developed. The key steps involved in the synthesis were palladium-mediated Heck reaction followed by aza heterocyclic ring construction by nucleophilic heteroannulation. This four-step sequence synthetic protocol gave moderate to good yields for a wide range of substrates. Subsequently, functionalization of the synthesized compound was carried out under Heck and Suzuki reaction conditions.

A new procedure for the treatment of an industrial waste containing flotation reagents

Flotation reagents can be transformed to industrial waste if they are stored for a long period of time. Also, if synthesis or drying process is not performed under defined conditions in industrial plants, which produce flotation reagents, batch of waste may arise and be stored as a waste. The chemical composition of this waste depends on the phase in which it was created, but typically includes: unreacted alkali hydroxide, solvent - alcohol and trithiocarbonate and oxidation product - dixanthogenate. In this paper a new laboratory procedure for the treatment of such wastes is described. The identification and separation of industrial waste components is also included. From the separated dixantogenate and xanthate a laboratory synthesis of thioncarbamates is given. In addition, a semi-industrial treatment of waste xanthate is presented. Synthesis of N-alkyl and N,N-dialkyl-O-isobutylthioncarbamates were obtained from the filtrate obtained in the first step. As a by-product, sodium thioglycolate was produced. This by-product is transformed to a thioglycolic acid by the addition of an acid. Also, the synthesis of thioncarbamates from dixanthogenates, isolated from industrial waste as a cake, is desribed. Described waste treatment is additionally interesting due to the production of sulphur as another by-product. Laboratory synthesis gave thioncarbamates in yields from 69.7 to 87.7 %, while the semi-industrial process for the selected batches produced thioncarbamates in yields from 74.2 to 80.5 %. Taking into account the importance of the synthesized compounds as selective flotation reagents, a new procedure of their synthesis from industrial waste is characterized by good yields and purity of the obtained compounds, the simplicity of process, low environmental impact and short reaction times of synthesis.

A Simple, One-Pot Synthesis of N-Alkyl and N-Aryl Thieno[2,3-d]pyrimidinones from Thiophene- and Benzothiophene-2-yl-ureas

We herein describe a convenient, one-pot synthesis of N-substituted thieno and benzothieno[2,3-d]pyrimidinones from the respective thiophene-2-yl ureas. This intramolecular cyclization, which presumably proceeds via a Vilsmeier–Haack dimethyliminium intermediate, has proven to be regioselective when performed in the presence of N,N′-bisarylureas and allows for independent functionalization of the pyrimidinone N3 and C4 positions.

Fast and Efficient Synthesis of Sulfinamides by the Oxidation of Sulfenamides Using Potassium Fluoride and m-Chloroperoxybenzoic Acid

A procedure for the synthesis of N-alkyl-, N-cycloalkyl-, N,N-dialkyl-, and N-arylarenesulfinamides from the corresponding sulfenamides using KF/m–chloroperoxybenzoic acid (CPBA) in CH3CN-H2O is described. High efficiency (fast reactions, ease of manipulation, and good yields) and absence of overoxidation are the major advantageous features of this protocol.

Synthesis of N-alkyl and N-aryl isoquinolones and derivatives via Pd-catalysed C–H activation and cyclization reactions

Relatively less expensive Pd-catalysed oxidative coupling reactions for the preparation of N-alkyl and N-aryl substituted isoquinolones and their derivatives have been developed. A broad reaction scope has been demonstrated. In addition, studies of the reaction additives and mechanistic insights, as well as KIE studies for a better understanding of the reaction pathway, have been discussed.

Comparative analysis of oxidative synthesis of N-alkyl, N,N-dialkyl and N-cykloalkyl-O-isobutyl thioncarbamate

A optimized synthesis of N-alkyl, N,N-dialkyl- and N-cycloalkyl-O-isobutyl thioncarbamates by aminolysis of sodium isobutylxanthogenic acid (NaiBXAc) and primary, secondary and cycloalkyl amines was developed at laboratory scale and applied at semi-industrial level. Studies on dependence of N-n-propyl-O-isopropylthiocarbamate yield and purity with respect to reaction parameters: reaction time and molar ratio of n-propylamine and NaiBXAc, were performed. In such way, optimal reaction conditions for synthesis of N-alkyl, N,N-dialkyl- and N-cycloalkyl-O-isobutyl thioncarbamates, by aminolysis of NaiBXAc, were established. Also, comparative results of thioncarbamates synthesis starting from potassium isobutyl xanthate (KiBX) and corresponding amines in presence of different oxidants: hydrogen peroxide, sodium hypochlorite and new oxidative agent potassium peroxodisulfate were evaluated. Synthesized compounds have been fully characterized by FTIR, 1H and 13C NMR and MS data, elemental analysis and purity have been determined by gas chromatographic method (GC). According to our knowledge, ten synthesized thioncarbamates are for the first time characterized. Synthesized compounds could be used as selective reagents for flotation of copper and zinc ores. The presented methods offer several benefits, namely, high product yields and purity, simple operation, mild reaction conditions without use of hazardous organic solvents, while some of them could be implemented on industrial scale production.

ChemInform Abstract: Synthesis of N-Alkyl-(α-aminoalkyl)phosphine Oxides and Phosphonic Esters as Potential HIV-Protease Inhibitors, Starting from α-Amino Acids.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A synthesis of N-alkyl and N,N-dialkyl O-ethyl thiocarbamates from diethyl dixanthogenate using different oxidants

A novel synthesis of N-alkyl and N,N-dialkyl O-ethyl thiocarbamates from diethyl dixanthogenate and primary and secondary amines, using three oxidizing sys- tems, has been developed on the laboratory scale, and the method using sodium hypochlorite has been applied on a semi-industrial scale. The effect of the oxidizing agents, sodium hypochlorite, in-situ-generated peracetic acid, and the manganese(II) acetate/oxygen system on product purity and yield was studied. The results obtained by use of these three methods were compared with those obtained by reaction of sodium ethyl xanthogenacetate and amines, and of sodium ethyl xanthate with amines in the presence of sulfated nickel zeolite catalyst. The reaction mechanism of sodium hypochlorite oxidation has been established on the basis of isolation of reaction intermediates and determina- tion of their structure by use of Fourier-transform infrared, 1 H and 13 C NMR, and mass spectrometric methods. The suggested sodium hypochlorite and manganese(II) acetate/ oxygen systems have many advantages in comparison with commercial and catalytically promoted synthetic methods, because they are new ecologically friendly syntheses.

New method for synthesis of N-alkyl and N,N-dialkyl-O-ethyl and O-isopropylthiocarbamates by oxidation of ammonium salt of xhantogenic acid

A synthesis of N-alkyl and N,N-dialkyl-O-ethyl and O-isopropyl thiocarbamates by oxidation of ammonium salt of ethyl and isopropylxanthogenic acid in a presence of sodium hypochlorite and hydrogen peroxide were performed. Ammonium salt of ethyl and isopropylxanthogenic acid was obtained by the reaction of alkylammonium sulfate and sodium ethyl and isopropyl xanthate. Studies on a dependence of N-ethyl-O-isopropylthiocarbamate yield and purity with respect to reaction parameters (reaction time, molar ratio of oxidant and ethylamonium salt of isopropylxanthogenic acid) were performed. Optimal reaction conditions for synthesis of N-alkyl and N,N-dialkyl-O-ethyl and O-isopropyl thiocarbamates were established. Synthesized compounds have been fully characterized by FTIR, 1H NMR and MS data, while purity has been determined by GC method. A plausible pathway for the N-alkyl and N,N-dialkyl-O-ethyl and O-isopropyl thiocarbamates synthesis, in the presence of the oxidative agents sodium hypochlorite and hydrogen peroxide, was proposed. The presented synthetic methods has been developed at laboratory and applied at semi-industrial level. The developed optimal method provides a powerful and versatile method for the preparation of N-alkyl and N,N-dialkyl-O-ethyl and O-isopropyl thiocarbamates. This new optimized method offer several benefits, namely, simple operation, mild reaction conditions, bypass of hazardous organic solvents, moderately toxic and inexpensive reagents, and also short reaction times and high product yields.

Polyethylene Glycol as a Nonionic Liquid Solvent for the Synthesis of N-Alkyl and N-Arylimides

Polyethylene glycol (PEG) an inexpensive, nontoxic, environmentally friendly reaction medium for the synthesis of N-alkyl and N-arylphthalimides to afford the corresponding adducts in excellent yields under mild reaction conditions. The use of PEG avoids the use of acidic or basic catalysts, and moreover PEG could be recovered and reused.