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A new, simple, rapid and moderate to high yielding syn-thesis of various 4-alkynyl-1,2-dimethyl-5-nitro-1H-imidazoles via Sonogashira palladium-catalyzed cross-coupling using microwave irradiation is described. [ABSTRACT FROM AUTHOR]

A mild and metal-free regioselective 1,2-addition of carbon nucleophiles to α,β-unsaturated imines has been developed. Good yields and total regioselectivities were achieved by addition of p-nitrobenzyl chloride or 2,3-bis(bromomethyl)quinoxaline to α,β-unsaturated tosylimines. [ABSTRACT FROM AUTHOR]

A series of new substituted diphenylquinolines and acenaphtho[1,2-b]quinolines was prepared in good yields according to a two-step synthesis using the TDAE methodology from substituted o-nitrobenzyl chlorides and α-diketones followed by a reduction-cyclization-dehydration step. [ABSTRACT FROM AUTHOR]

Anthracycline antibiotics play an important role in cancer chemotherapy. The need to improve their therapeutic index has stimulated an ongoing search for anthracycline analogs with enhanced properties. This review aims to summarize the common synthetic approaches to benzo[g]quinoxaline-5,10-diones and their uses in heterocyclic chemistry. Because of the valuable biological activities of the 1,4-diazaanthraquinone compounds, a summary of the most promising heterocyclic quinones is provided together with their antitumor properties. [ABSTRACT FROM AUTHOR]

An easy and efficient method of diastereoselective synthesis of N-tert-butanesulfinylamines using a TDAE strategy was developed. Good yields and diastereoselectivities were achieved using readily available N-tert-butanesulfinimines and commercially available p-nitrobenzyl chloride. [ABSTRACT FROM AUTHOR]

We describe an original pathway to produce new 5-substituted 3-methyl-6-nitrobenzoxazolones by the reaction of aromatic carbonyl and a-carbonyl ester derivatives with a benzoxazolinonic anion formed exclusively via the TDAE strategy. [ABSTRACT FROM AUTHOR]

Abstract: We report here the first example of an SRN1 reaction on propargylic chloride in heterocyclic series. The reaction of 4-(3-chloroprop-1-ynyl)-1,2-dimethyl-5-nitro-1H-imidazole with nitronate anions led to both the formation of the C-alkylated product through an SRN1 mechanism and the predominant ethylenic compound resulting from nitrous acid elimination on the C-alkylated product. Interestingly, in contrast to our previous works on SRN1 reactivity, no O-alkylated product was observed. [Copyright &y& Elsevier]

• A new series of N-functionalized thiazolidinones has been synthesized and characterized. • The DFT approach has been used to correlate the experimental data. • N-functionalized thiazolidinone derivatives' antibacterial activity was assessed. • N-functionalized thiazolidinones' ADME-T properties have been studied. • The in silico study of the inhibition of DNA gyrase II has been performed. A new series of N-functionalized thiazolidinones has been synthesized in three steps. Physicochemical and spectroscopic techniques, such as melting point analysis, IR, 1H and 13C NMR have been used to characterize the synthesized compounds. With the aid of density functional theory (DFT), the synthesized compounds optimized molecular structures, IR spectra modeling, reactivity, stability, and several quantum chemical characteristics were all modeled. It was demonstrated that there is significant agreement between the experimental and theoretical results. Furthermore, the antibacterial activity of the compounds under investigation was assessed in order to specifically comprehend the associated mechanisms of action. They also demonstrated good oral bioavailability, according to projected ADME-T and pharmacokinetic parameters. Molecular docking has also been used to predict the inhibitory effect of the investigated drugs on DNA gyrase II. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: We report herein an original and rapid synthesis of substituted 2-tosyl-1,2,3,4-tetrahydropyrido[3,4-b]quinoxaline derivatives by TDAE strategy from 2,3-bis(bromomethyl)quinoxaline and N-(toluenesulfonyl)benzylimines. [Copyright &y& Elsevier]

Abstract: New reductive alkylating agents in 4- and 5-nitroimidazole series produce exclusively O-alkylation with nitronate anions under classical SRN1 conditions at room temperature. Electron-transfer C-alkylation is observed under microwave irradiation or under conventional heating. Furthermore, X-ray spectroscopy shows that the dihedral angles between the phenyl and imidazole rings for the two series are different, which could greatly influence reactivity in 4- and 5-nitroimidazole series. [Copyright &y& Elsevier]

Abstract: A series of new imidazo[2,1-b]thiazoles was prepared in moderate to good yields in a four step synthesis using the TDAE methodology from 6-chloromethyl-5-nitroimidazo[2,1-b]thiazole and keto esters, ketomalonates and ketolactams. All compounds were tested for their antibacterial and antifungal activities against four bacterial strains (two Gram positive and two Gram negative ones) and four yeasts. Among these synthesized 5-nitroimidazo[2,1-b]thiazoles, the compounds 1 and 6 showed potent antimicrobial activities against all candida strains and compound 3e showed an interesting antifungal potential against Candida tropicalis. [Copyright &y& Elsevier]

Abstract: We report herein an original preparation of 2-substituted 1,4-dimethoxy-9,10-anthraquinones using the first example of TDAE strategy in quinonic series. This TDAE approach is an original and mild method to generate a quinonic anion, which cannot be formed via organometallic strategy. [Copyright &y& Elsevier]

Abstract: We developed a rapid and green synthesis of various isocyanurates by cyclotrimerization of isocyanates using TDAE (tetrakis(dimethylamino)ethylene). TDAE displays excellent performance in catalytic quantities, affording the corresponding trimer of isocyanates very rapidly, under air and at room temperature in good to excellent yields. [Copyright &y& Elsevier]

A one-pot synthesis of new 3-benzylphthalide derivatives was developed by using a strategy based on tetrakis(dimethylamino)ethylene (TDAE). The reactions in the presence of TDAE of substituted benzyl chlorides with methyl 2-formylbenzoate or of substituted methyl-2-formylbenzoates with 4-nitrobenzyl chloride furnished the corresponding isobenzofuran-1(3 H)-one products in moderate to good yields. [ABSTRACT FROM AUTHOR]

Rhinovirus (RV), member of the Enterovirus genus, is known to be involved in more than half of the common colds. Through advances in molecular biology, rhinoviruses have also been associated with exacerbations of chronic pulmonary diseases (e.g. asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis). In the current investigation, we develop a novel series of 4,5-dimethoxybenzyl derivatives that potently inhibits rhinovirus replication. Compound (S) -7f blocks RV-B14 replication with an EC 50 value of 0.25 μM and shows a low toxicity in HeLa cells (CC 50 > 271 μM). Enantioseparation followed by an absolute configuration determination by a Mosher's method revealed the interest of enantiopure compounds. Molecular docking studies permitted the identification of key biological interactions within the drug-binding pocket and an in silico drug-like study revealed a good potential for the development of these derivatives. [ABSTRACT FROM AUTHOR]

We report a novel series of quinoxaline derivatives from which agents with antiproliferative activity have been identified. Two ethyl 3-(arylethynyl)quinoxaline-2-carboxylates demonstrated substantial antiproliferative activity against both human non-small cell lung carcinoma (A549) and glioblastoma (U87-MG) cell lines. Pyrido[4,3- b ]quinoxalin-1(2 H )-ones demonstrated poor activity against A549 and U87-MG cell lines. Three of the derivatives in ethyl 3-(arylethynyl)quinoxaline-2-carboxylate series demonstrated substantial antiproliferative activity. The arylethynyl derivative 2a and 2d proved to be the most cytotoxic with an IC 50 value of 3.3 μM for both A549 and U87-MG cell lines. [ABSTRACT FROM AUTHOR]

We report here a practical and metal-free synthesis of novel enantiopure amides containing the drug-like 5-nitroimidazole scaffold. The first step was a metal-free diastereoselective addition of 4-(4-(chloromethyl)phenyl)-1,2-dimethyl-5-nitro-1H-imidazole to enantiomerically pure N-tert-butanesulfinimine. Then, the N-tert-butanesulfinyl–protected amine was easily deprotected under acidic conditions. Finally, the primary amine was coupled with different acid chlorides or acids to give the corresponding amides. The mild reaction conditions and high tolerance for various substitutions make this approach attractive for constructing pharmacologically interesting 5-nitroimidazoles. [ABSTRACT FROM AUTHOR]

Human rhinoviruses (HRV) are the predominant cause of common colds and flu-like illnesses, but are also responsible for virus-induced exacerbations of asthma and chronic obstructive pulmonary disease. However, to date, no drug has been approved yet for clinical use. In this study, we present the results of the structure-based lead optimization of a class of new small-molecule inhibitors that we previously reported to bind into the pocket beneath the canyon of the VP1 protein. A small series of analogues that we designed based on the available structure and interaction data were synthesized and evaluated for their potency to inhibit the replication of HRV serotype 14. 2-(4,5-Dimethoxy-2-nitrophenyl)-1-(4-(pyridin-4-yl)phenyl)ethanol ( 3v ) was found to be a potent inhibitor exhibiting micromolar activity (EC 50 = 3.4 ± 1.0 μM) with a toxicity for HeLa cells that was significantly lower than that of our previous hit (LPCRW_0005, CC 50 = 104.0 ± 22.2 μM; 3v , CC 50 > 263 μM). [ABSTRACT FROM AUTHOR]

Polymerization reactions with organic electron donors (OED) as initiators are presented herein. The metal-free polymerization of various activated alkene and cyclic ester monomers was performed in short reaction times, under mild conditions, with small amounts of organic reducing agents, and without the need for co-initiators or activation by photochemical, electrochemical, or other methods. Hence, OED initiators enabled the development of an efficient, rapid, room-temperature process that meets the technical standards expected for industrial processes, such as energy savings, cost-effectiveness and safety. Mechanistic investigations support an electron-transfer initiation pathway that leads to the reduction of the monomer. [ABSTRACT FROM AUTHOR]

Studies directed toward the oxidative and reductive desulfurization of readily available 2′- S -aryl-2′-thiouridine derivatives were investigated with the prospect to functionalize the C2′-position of nucleosides. The oxidative desulfurization-difluorination strategy was successful on 2-(arylthio)alkanoate surrogates, while extension of the combination of oxidants and fluoride sources was not an efficient fluorination protocol when applied to 2′- S -aryl-2′-thiouridine derivatives, resulting mainly in C5-halogenation of the pyrimidine ring and C2′-monofluorination without desulfurization. Cyclic voltammetry of 2′-arylsulfonyl-2′-deoxyuridines and their 2′-fluorinated analogues showed that cleavage of the arylsulfone moiety could occur, although at relatively high cathodic potentials. While reductive-desulfonylation of 2′-arylsulfonyl-2′-deoxyuridines with organic electron donors (OEDs) gave predominantly base-induced furan type products, chemical (OED) and electrochemical reductive-desulfonylation of the α-fluorosulfone derivatives yielded the 2′-deoxy-2′-fluorouridine and 2′,3′-didehydro-2′,3′-dideoxy-2′-fluorouridine derivatives. These results provided good evidence of the generation of a C2′-anion through carbon-sulfur bond cleavage, opening new horizons for the reductive-functionalization approaches in nucleosides. [ABSTRACT FROM AUTHOR]

The article presents chemical equations of the article "Mild and Metal-Free Diastereoselective Synthesis of N-tert-Butanesulfinylamines by Using Tetrakis(dimethylamino)ethylene" by C. Spitz and others, published in the periodical "Synthesis" in 2014.

The article presents chemical equations related to the article First Single Electron Transfer Reaction on Propargylic Chloride in 5-Nitroimidazole Series" by K. Neilde and others, published in the periodical "Tetrahedron Letters" in 2014.

Thiosulfonate derivatives based on quinones were synthesized for studying "structure-activity relationship" compounds with an acylated and a free aminogroup. Anti-platelet activity of the synthesized compounds was determined and the influence of substituents on the activity of the derivatives was assessed. [ABSTRACT FROM AUTHOR]

Following the promising antileishmanial results previously obtained in monoamidoxime series, a new series of derivatives was synthesized using manganese(III) acetate, Wittig reactions and Suzuki–Miyaura cross coupling reactions. Pharmacomodulation in R 1 , R 2 or R 3 substituents on the amidoxime structure is shown to influence antiprotozoan activity in vitro : a monosubstituted phenyl group in R 1 ( 32 – 35 ) led to an activity against Leishmania donovani promastigotes ( 32 , IC 50 = 9.16 μM), whereas a polysubstituted group ( 36 – 37 ) led to an activity against Plasmodium falciparum ( 36 , IC 50 = 2.76 μM). Modulating chemical substituents in R 2 and R 3 only influenced the antiplasmodial activity in vitro . This suggests that the amidoxime scaffold has properties that could make it a promising new antiparasitic pharmacophore. [ABSTRACT FROM AUTHOR]

Neuroblastoma is an aggressive pediatric malignancy with significant chemotherapeutic resistance. In order to obtain new compounds active on neuroblastoma cell lines, we investigated the reactivity of carbanion formed via TDAE in quinoxaline series. The new synthesized compounds were tested for their anti-proliferative activity on two neuroblastoma cell lines, and seven oxirane derivatives obtained interesting activities. [ABSTRACT FROM AUTHOR]

Abstract: Human rhinoviruses are a common cause of respiratory infections, and thus constitute an important target for medicinal chemistry. Still, no drug has been approved for clinical use. We report herein the discovery of dibenzenic derivatives with potent and specific in vitro anti-rhinoviral 14 activity. A total of 99 structural analogues were synthesized by an original synthesis method, i.e. through one organic agent Tetrakis(DimethylAmino)Ethylene (TDAE) and a structure–activity relationship was established. It was shown that 4,5-dimethoxy scaffold and the presence of a C-4 substituted aromatic moiety were necessary to the in vitro activity of these original agents. However, modifications on liker were not convincing. The benzonitrile derivative 23 was identified as the most potent and selective inhibitor of rhinovirus replication in these series (EC50 of 2 ± 0.5 μM, CC50 of 184 μM, selectivity index of 92). [Copyright &y& Elsevier]

We present herein the synthesis in good yields of two series of highly functionalized thiazolidinone derivatives from the reactions of various 4-phenyl-3-thio-semicarbazones with ethyl 2-bromoacetate and diethyl acetylenedicarboxylate, respectively. [ABSTRACT FROM AUTHOR]