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A nano-biosensor based on graphene oxide (GO) and 5-carboxy fluorescein (FAM) labeled DNA was developed for the detection of deletion mutation in exon 19 of EGFR gene, which led to the lung cancer. The method is based on the adsorbtion of FAM-labeled single-stranded DNA (fDNA) on GO, leading to fluorescence quenching of FAM. By addition of its complementary DNA (cDNA), a double-stranded DNA (dsDNA) was formed, resulted in recovering of fluorescence of FAM by desorbing and releasing from GO. While in the case of mismatched DNA, corresponding dsDNA was not formed, and therefore the fluorescence of FAM was not recovered.

2-[(2-Pyridylmethyl)amino]acetic acid (PMAA) functionalized Fe3O4 superparamagnetic nanorods efficiently catalyzed three-component reaction of malononitrile, aromatic aldehydes and phenolic or enolic components, such as α-naphthol, β-naphthol, dimedone or kojic acid, to synthesize a variety of chromene or pyran derivatives in good to high yields. PMAA functionalized Fe3O4 magnetic nanorods were prepared via simple coprecipitation from an aqueous solution of Fe2+ and Fe3+ ions using NH4OH in the presence of glycine, followed by subjecting with 2-pyridine carbaldehyde and then NaBH4-mediated reduction of in-situ generated imine. Obtained nanorods were characterized by FT-IR, XRD, TGA, SEM, EDX, TEM, BET and VSM analysis.

α-Imino esters are useful precursors for the synthesis of a variety of types of natural and unnatural α-amino acid derivatives, with a wide range of biological activities. Due to the adjacent ester group, α-imino esters are more reactive relative to other types of imines and undergo different kinds of reactions, including organometallics addition, metal catalyzed vinylation and alkynylation, aza-Henry, aza-Morita-Baylis-Hillman, imino-ene, Mannich-type, and cycloaddition reactions, as well as hydrogenation and reduction. This review discusses the mechanism, scope, and applications of the reactions of α-imino esters and related compounds in organic synthesis, covering the literature from the last 12 years.

A series of new 1,2,3-triazole derivatives were synthesized by 1,3-dipolar cycloaddition reaction of 2-(4-azidomethylphenyl)-6-phenyl-4H-pyran-4-one with different alkynes in 40–71% yields. In the case of terminal alkynes, the reaction was proceeded in the presence of Cu(I) catalyst. The structure of the synthesized compounds were confirmed by FTIR, 1H-NMR, and 13C-NMR spectroscopy and elemental analysis.

The Heck coupling of haloarenes with various alkenes was successfully performed in the presence of 0.25 mol % PdCl2 and 0.5 mol % biphenyl-4-yl-[4(5)-(biphenyl-4-yl)-1H-imidazol-2-yl]ketone 2f as a ligand with Na2CO3 as optimal base, in a 1:1 mixture of H2O/DMF as the reaction solvent at 80 °C for 8 h. Imidazole 2f was found to be an inexpensive, air-stable, easily available, and efficient ligand in the palladium-catalyzed Heck reactions of aryl iodides (76 %--94 %), bromides (52 %--79 %), and chlorides (40 %--70 %).

A green and efficient method for the synthesis of 5-amino-1-aryl-1H-tetrazoles with excellent yields and high purity from secondary arylcyanamides is described. This method is completely green because no organic solvents or protic acid catalyst is used that can generate hydrazoic acid (HN3). In addition, it is a very clean method for acquiring 5-amino-1-aryl-1H-tetrazoles without generating 5-arylamino-1H(2H)-tetrazoles in most cases.

An oxido-peroxido tungsten(VI) complex [WO(O2)L(CH3OH)] using salicylidene benzoyl hydrazine as a tridentate ONO donor Schiff base (H2L) has been synthesized and characterized by elemental analysis, IR, 1H NMR, molar conductance data, and single-crystal X-ray analysis. The complex was used as a catalyst for epoxidation of olefins and oxidation of sulfides. The results show that epoxides and sulfoxides were produced in high yield, turnover number, and selectivity.

A green and simple method to synthesize of 1,4-diketones via aldol reaction of arylglyoxals and ketones such as 1-(4-methoxyphenyl)-2-propanone, deoxybenzoin and substituted acetophenones in the presence of a catalytic amount of DABCO in water at room temperature has been reported. Corresponding 2-hydroxy-1,4-diones were obtained in moderate to high yields with simple separation of obtained solid from reaction mixture and recrystallization.

Eftekhari-Sis, Bagher/0000-0001-8998-8040 WOS: 000318399000014 Willgerodt-Kindler reaction of arylglyoxal hydrates with secondary amines and elemental sulfur under solvent-free conditions at 80 degrees C is developed, in which alpha-ketothioamides are obtained in 70-90% yield in 0.6-1 hour. The X-ray crystal-structure analysis for one compound was obtained. Research Council of the University of Maragheh This work was supported by the Research Council of the University of Maragheh. B.E.S. gratefully acknowledges Mr. Biglari (IASBS) for recording NMR spectra.

A green and efficient method for the preparation of 5-aryl-4-hydroxy-2-methyl-1H-pyrrole-3-carboxylic acid esters and 6-aryl-3-methylpyridazine-4-carboxylic acid esters via three-component reaction of arylglyoxal hydrates with β-dicarbonyl compounds in the presence of ammonium acetate and hydrazine hydrate using water as solvent under ultrasonic irradiation was reported. The reactions proceeded rapidly and afforded the corresponding pyrroles and pyridazines in good to high yields in very short reaction time.

A simple and efficient method for the synthesis of α-ketothioamides via the Willgerodt–Kindler reaction is developed. Reactions were carried out between arylglyoxal hydrates, amines and elemental sulfur in water at 80°C to afford corresponding α-ketothioamides in good to high yields in a short reaction time.

A method was developed for the detection of 185delAG mutation in BRCA1 gene, which is responsible for 85% and 63% lifetime risks of hereditary breast and ovarian cancer in women, respectively. The protocol is based on the quenching and recovering fluorescence emission of fluorescein-based dye (FAM)-labeled DNA in the presence of graphene oxide (GO), followed by addition of cDNA or mDNA. In addition, ligase reaction between a DNA probe attached to GO and a DNA possessing FAM on 5' terminal in the presence of cDNA or mDNA was applied.

The reactions of kojic acid in organic synthesis are reviewed. The aim of this review is to cover the literature up to the end of 2014, showing the distribution of publications involving kojic acid chemistry in the synthesis of various pyrone containing compounds, pyridine and pyridone heterocycles, and also other organic compounds. First, introductory text about the preparation, biological, and industrial applications, and the chemical properties of kojic acid is given. Then its uses in organic synthesis are presented considering the reaction type.

At room temperature, zirconium oxychloride (ZrOCl2·8H2O) efficiently catalyzes the direct Mannich-type reaction of a variety of in situ generated bis-imines using terephthalaldehyde and anilines with ketones in a three-component reaction at room temperature. The reaction proceeds rapidly and affords the corresponding bis-β-amino ketones in good-to-high yields with good-to-excellent anti–anti selectivity.

New N-alkyl(aryl)-2,4-diaryl-1H-pyrrol-3-ol derivatives have been synthesized in moderate to good yields in a novel and efficient process by aldol reaction of 1-(4-methoxyphenyl)propan-2-ones with phenylglyoxal in the presence of DABCO in water, followed by Paal–Knorr reaction with amines in the presence of a catalytic amount of p-TSA in toluene at reflux.

At room temperature, and efficiently catalyze the direct Mannich-type reaction of varieties of in situ–generated aldimines using aldehydes and anilines with ketones in a three-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding β-amino ketones in good to high yields with good to excellent stereoselectivity. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.

Eftekhari-Sis, Bagher/0000-0001-8998-8040; Mahdavinia, Gholam Reza/0000-0003-2004-0774 WOS: 000370067900003 A new polymeric laponite nanoclay heterogeneous catalytic system based on HPMC (hydroxypropyl methyl cellulose) was developed for direct Mannich-type reaction of ketones with substituted benzaldehydes and anilines to afford corresponding beta-amino ketones in good to high yields. Interestingly, cyclic ketones exhibited different chemoselectivity. Cyclopentanone underwent aldol condensation to give crossed-aldol product, while cyclohexanone and cyclopentanone afforded corresponding Mannich adducts. In the case of cyclohexanone, stereoselectivity was changed depending on the nature of the substitution on benzaldehydes, in which, moderate electron-donating and electron-withdrawing groups afforded the anti isomer as major products, but strongly electron-donating substituted benzaldehydes led to syn isomer as the major Mannich adducts. Mannich reaction with cycloheptanone led to Mannich adducts with excellent syn selectivity. Research Council of the University of Maragheh The Research Council of the University of Maragheh is acknowledged for financial support.

Red mud (RM) which emerges as a by-product from the alumina producing process has been used as an efficient catalyst for one-pot direct synthesis of nitrile compounds from aldehydes and hydroxylamine hydrochloride under microwave irradiation.

At room temperature, alcohols and phenols are efficiently protected with hexamethyldisilazane (HMDS) in the presence of silica sulfuric acid in good to excellent yields. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.

Red mud (RM) is generated as a by-product during the production of alumina from bauxite ore. In this study, RM packing in a column is used as a catalyst for carbon–carbon double bond formation via Knoevenagel condensation. The reactants are added to the top of the column and then eluted with solvent. The products are collected in high yields and short time. RM packed in a column eliminates a catalyst separation step from the reaction mixture in this work.

The reactions of kojic acid in organic synthesis are reviewed. The aim of this review is to cover the literature up to the end of 2014, showing the distribution of publications involving kojic acid chemistry in the synthesis of various pyrone containing compounds, pyridine and pyridone heterocycles, and also other organic compounds. First, introductory text about the preparation, biological, and industrial applications, and the chemical properties of kojic acid is given. Then its uses in organic synthesis are presented considering the reaction type.

At room temperature, zirconium oxychloride (ZrOCl2·8H2O) efficiently catalyzes the direct Mannich-type reaction of a variety of in situ generated aldimines using aldehydes and anilines with ketones in a three-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding β-amino ketones in good to high yields with good to excellent stereoselectivities. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

A green and efficient method for the synthesis of 5-amino-1-aryl-1H-tetrazoles with excellent yields and high purity from secondary arylcyanamides is described. This method is completely green because no organic solvents or protic acid catalyst is used that can generate hydrazoic acid (HN3). In addition, it is a very clean method for acquiring 5-amino-1-aryl-1H-tetrazoles without generating 5-arylamino-1H(2H)-tetrazoles in most cases.

Phenols were oxidized to quinones using sodium perborate (SPB) on wet montmorillonite as oxidant. The reaction was carried out at ambient temperature on the solid phase under solvent free conditions. Fenóis foram oxidados a quinonas usando perborato de sódio (SPB) em montmorilonita úmida, como oxidante. A reação foi conduzida em fase sólida, a temperatura ambiente e sem a utilização de solventes.

In the title compound, C20H23NO, the cycloheptanone ring adopts a twist-chair conformation, with the aminomethyl substituent in an equatorial position. The relative configuration of the two stereocenters is R,R. In the crystal, molecules are linked by N—H...O hydrogen bonds into chains along [100].

Fully substituted pyrrol-3-ol derivatives (V) are prepared via aldol reactions of propane-2-one with phenylglyoxal followed by Paal—Knorr reaction with amines.

For the first time, the Baylis-Hillman (BH) reaction of 2H-thiopyran-4(3H)-one is investigated, and surprisingly, the reaction of 2H-thiopyran-4(3H)-one with aldehydes in the presence of different tertiary amines shows excellent chemo- and regioselectivity in water. At room temperature, DBU affords BH adducts, but with DABCO, aldol products were obtained. In the case of DABCO, Et(3)N, or DMAP, domino aldol-rearrangement reactions occurred at 45-50 °C.

Novel 2-aryl-4-chloro-3-hydroxy-1H-indole-5,7-dicarbaldehydes (III) are obtained in a three-step procedure from acetophenones.

Novel 2-aryl-4-chloro-3-hydroxy-1H-indole-5,7-dicarbaldehydes (III) are obtained in a three-step procedure from acetophenones.

New 2-alkyl-5-aryl-(1H)-pyrrole-4-ol derivatives were synthesized via three-component reaction of beta-dicarbonyl compounds with arylglyoxals in the presence of ammonium acetate in water at room temperature.

New 2-alkyl-5-aryl-(1H)-pyrrole-4-ol derivatives were synthesized via three-component reaction of beta-dicarbonyl compounds with arylglyoxals in the presence of ammonium acetate in water at room temperature.

At room temperature, ZrOCl2·8H2O on montmorillonite K10 efficiently catalyzes conjugate addition of amines to a variety of conjugated alkenes such as α,β-unsaturated carbonyl compounds, carboxylic esters, nitriles and amides under solvent-free conditions. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.

A solid state method for the oxidation of phenols to quinones is described using ammonium persulfate/wet silica gel as oxidant.

Manganeses(II) chloride supported on montmorillonite K10 was found to be an efficient catalysts for the oxidation of alcohols to carbonyl compounds with hydrogen peroxide as oxidant.

A solid state method for the oxidation of phenols to quinones is described using ammonium persulfate/wet silica gel as oxidant