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Substituted triazolinones were prepared by a three-component reaction of aldehydes, hydrazines and azodicarboxylates using TFA as a catalyst. The procedure was convenient and efficient, utilizing readily available substrates. A plausible mechanism for the cascade process is proposed. [ABSTRACT FROM AUTHOR]

In this work, we evaluated the antioxidant properties of the eight novel silybin analogues for their capacity to scavenge free radicals including superoxide anion radicals and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals in vitro . Compound 7d demonstrated an excellent antioxidant effect in scavenging superoxide anion free radical with an IC 50 value of 26.5 μM, while the IC 50 of quercetin (the reference compound) was 38.1 μM. Compounds 7b , 7e , 7h showed certain scavenging activities for both types of free radicals. [ABSTRACT FROM AUTHOR]

A three-component reaction of indoles, sulfonyl azides and terminal alkynes afforded 3-functionalized indoles in a single step viacopper-cascade catalysis. [ABSTRACT FROM AUTHOR]

Abstract: A one-pot synthesis of quinolines via molecular iodine-catalyzed and air-mediated tandem condensation/imino-Diels–Alder/isomerization/oxidation of simple readily available amines, aldehydes, and alkynes has been developed. This methodology was extended to synthesize quinazolines from two molecules of amines and two molecules of glyoxalates. [Copyright &y& Elsevier]

Abstract: Eleven shikonin glycosides were synthesized and evaluated for their antitumor activity in vitro. Some of them were found to exhibit cytotoxic activities against both drug sensitive cell lines (K562, MCF-7 and HL60) and their drug resistant cell sublines (K562/ADR, MCF-7/ADR and HL60/ADR). [Copyright &y& Elsevier]

Abstract: A series of 2,3-diiodoindene were synthesized at first, and 13H-indeno[1,2-l]phenanthrenes were then constructed via a Suzuki coupling reaction and subsequently a Scholl reaction. Structures of synthesized compounds were fully characterized by 1H NMR, 13C NMR, and HRMS. Their photophysical properties, such as UV–vis and FL spectra were investigated, and electronic properties were theoretically calculated by the software of Gaussian 03. The results suggested that these modified indene and indenophenanthrene compounds might have potential applications as light emitting materials. [Copyright &y& Elsevier]

Abstract: In this work, cis-2,5-disubstitutedoxazolidines were efficiently constructed via a regioselective C–C bond cleavage of N-tosylaziridine 2,2-dicaboxylates and a subsequent [3+2] cycloaddition with aromatic aldehydes in the presence of Zn(OTf)2. The reactions were highly diastereoselective to form oxazolidines in cis configurations. trans-2,5-Disubstituted imidazolidines were also diastereoselectively synthesized in the similar manner using imines as substrates and AgOTf as catalyst. Based on the detailed investigation of the substrate diversity for both reactions, including the electronic effects and the steric effects of the substituted groups on the aziridines, aldehydes, and imines, a stepwise mechanism was postulated for the diastereoselective formation of cis-2,5-disubstitutedoxazolidines and trans-2,5-disubstituted imidazolines. [Copyright &y& Elsevier]

Abstract: 2H-Chromen-2-ones (coumarins) and 4H-chromen-4-ones (flavones) were selectively prepared via the reaction of 3-(2-hydroxyphenyl)propiolates with iodine in toluene and N,N-dimethylformide, respectively. [Copyright &y& Elsevier]

Abstract: One-pot synthesis of 2-(N-sulfonylimino)indolines has been developed. The procedure combines the copper-catalyzed three-component reaction of sulfonyl azides, o-bromophenylacetylenes, and amines and the copper-catalyzed intramolecular C–N coupling in one sequence, which afforded the products in moderate to good yields. The resulting 2-(N-sulfonylimino)indolines could be easily transformed to pharmaceutically valuable oxindoles (indolin-2-ones). [ABSTRACT FROM AUTHOR]

Abstract: A convenient method for the synthesis of 1,2,4-triazolines by triphenylphosphine-triggered reaction of dialkyl azodicarboxylate with 2-azidoacrylates is described. The cascade reaction procedure is general and efficient. [Copyright &y& Elsevier]

Abstract: A series of tetrafluorophenyl-modified oligo(3,6-carbazole ethynylene)s (CfCzCf, CfCz2Cf, CfCz3Cf, (CfCz)2Cf, and Cf2CzCf2) were synthesized by a Pd/Cu-catalyzed Sonogashira coupling reaction and fully characterized. Their photophysical and electronic properties as well as their thermal stabilities were investigated. It is noteworthy that these tetrafluorophenyl modified compounds showed relative thermal stabilities and low-lying HOMO levels ranging from −5.54 to −5.60eV, which might be the promising candidates for hole-transporting materials in OLEDs. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and general synthesis of 1,3-diazabicyclo[3.1.0]hex-3-enes via the copper-catalyzed cascade reaction of aziridines with ethyl diazoacetate is described. [ABSTRACT FROM AUTHOR]

Abstract: Substituted 4-amino-1,2,4-triazol-3-ones were synthesized from aldehyde hydrazones and azodicarboxylates in the presence of triphenylphosphine. The cascade reaction was conducted in a single step and the procedure is general and efficient. [Copyright &y& Elsevier]

Abstract: Polysubstituted amidines, benzimidazoles and pyrimidines were synthesized via the electrophilic activation of amides with trifluoromethanesulfonic anhydride and 2-chloropyridine. The one-pot protocol is concise and efficient and the substrates are readily available. [Copyright &y& Elsevier]

Abstract: A regioselective synthesis of 1,3,4,5-tetrasubstituted pyrazoles is established between 2-azidoacrylates and hydrazonyl chlorides in the presence of triethylamine. The yields are moderate (43–73%) and a possible mechanism for this transformation is postulated. [Copyright &y& Elsevier]