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A transition metal-free, one-pot protocol has been developed for the synthesis of 11 H -indolo[3,2- c ]isoquinolin-5-amines via the atom economical annulation of ethyl (2-cyano-phenyl)carbamates and 2-cyanobenzyl bromides. This method proceeds via sequential N-alkylation and base-promoted cyclization. Optimization data, substrate scope, mechanistic insights, and photoluminescence properties are discussed. [ABSTRACT FROM AUTHOR]

Abstract: The addition of various primary amines onto 3-α,β-unsaturated diester chromone derivative was studied under mild conditions. Basically, this reaction provided 2-pyridone-based compounds through an interesting domino ‘Addition/Ring Opening/Ring Closure’ process (ARORC). In this study, aniline and tryptamine series exhibited different reactivity profiles leading unexpectedly to 3-aminomethylene chromanones with or without the 2-pyridone derivatives. This constitutes the first description and study of 3-aminomethylene chromanone formation that is supposed to follow a domino process combining ‘Addition/Ring Opening/Ring Closure by Oxa-Michael addition’ (ARORCOM). [Copyright &y& Elsevier]

Abstract: We develop a strategic ‘domino’ approach that starts with one key feature of cell function and the main process providing for it, and then adds additional processes and components only as necessary to explain provoked experimental observations. The approach is here applied to the energy metabolism of yeast in a glucose limited chemostat, subjected to a sudden increase in glucose. The puzzles addressed include (i) the lack of increase in Adenosine triphosphate (ATP) upon glucose addition, (ii) the lack of increase in Adenosine diphosphate (ADP) when ATP is hydrolyzed, and (iii) the rapid disappearance of the ‘A’ (adenine) moiety of ATP. Neither the incorporation of nucleotides into new biomass, nor steady de novo synthesis of Adenosine monophosphate (AMP) explains. Cycling of the ‘A’ moiety accelerates when the cell''s energy state is endangered, another essential domino among the seven required for understanding of the experimental observations. This new domino analysis shows how strategic experimental design and observations in tandem with theory and modeling may identify and resolve important paradoxes. It also highlights the hitherto unexpected role of the ‘A’ component of ATP. [Copyright &y& Elsevier]

Abstract: We have developed a highly efficient one-pot approach to poly-substituted indolizinones from tertiary propargylic alcohols by using a palladium-catalyzed domino reaction. This reaction is proposed to proceed via successive aminopalladation, reductive elimination, and 1,2-shift. While our previous effort to the same skeleton via 2-iodoindolizinones selected α,β-unsaturated esters, terminal acetylenes, or boronic acids as coupling partners, this strategy introduces new functional groups at the C2 position of indolizinone core with (hetero)aryl halides or diallyl carbonate, expanding the substrate scope for decoration at the C2 site. Furthermore, a new preparation route to tertiary propargylic alcohols for this study is described to rapidly diversify the molecular framework. [Copyright &y& Elsevier]

Abstract: A novel class of 2,3-tri- and tetrasubstituted γ-butyrolactones analogous to paraconic acids has been synthesized in one step using a straightforward three-component reaction among aryl bromides, dimethyl itaconate and carbonyl compounds. The in vitro cytotoxic activity of representative compounds has been evaluated against a panel of human cancer cell lines (KB, HCT116, MCF7, HL60). While most molecules exhibit a low to moderate background activity on both KB and HL60 cancer cell lines, one compound shows increased antiproliferative activities against both cell lines with IC50 values in the 10−7–10−6 mol/L range. An extended evaluation indicated that this compound also inhibits PC3, SK-OV3, MCF7R and HL60R cell growth in the same fashion. [Copyright &y& Elsevier]

Abstract: A small library of peculiar biphenyl and terphenyl-containing spirocyclic triones has been synthesized in parallel by combining the organocatalytic three-component domino Knoevenagel/Diels–Alder sequence to Suzuki coupling. This methodology is fast, general and serves as a platform to gain access to novel chemical tools to probe protein–protein interactions. [Copyright &y& Elsevier]

Abstract: Substituted thiapyrrolizidinones and fused pyridones, and quinolizinones were reported efficaciously from suitable thioamides in yields ranging from 30% to 65%. The reaction proceeded in a one-pot procedure as cascade process by the intramolecular 1,3-dipolar cycloaddition of thioisomünchnones followed by desulfurization of the adducts. During these investigations, the mechanistic aspects of the process were also discussed. [Copyright &y& Elsevier]

Abstract: A new and efficient synthesis of furo[2′,4′:4,6]pyrano[2,3-b]quinolines, via a domino cyclization approach, has been achieved by iodine and mercuric oxide-catalyzed intramolecular cyclization of 3-homoallyl-2-quinolones in acetic acid. [Copyright &y& Elsevier]