20538-12-9Relevant academic research and scientific papers
Indoles via Knoevenagel-Hemetsberger reaction sequence
Heaner Iv, William L.,Gelbaum, Carol S.,Gelbaum, Leslie,Pollet, Pamela,Richman, Kent W.,Dubay, William,Butler, Jeffrey D.,Wells, Gregory,Liotta, Charles L.
, p. 13232 - 13242 (2013/09/02)
A series of substituted indoles have been synthesized by the sequential reaction of aromatic aldehydes with ethyl azidoacetate in the presence of sodium ethoxide to form the corresponding ethyl α-azido-β-arylacrylates (Knoevenagel process) followed by a solvent mediated thermolysis (Hemetsberger process). The isolated yields of the ethyl α-azido-β-arylacrylates were significantly increased when employing the sacrificial electrophile ethyl trifluoroacetate. 1H NMR and coupled 1H-13C NMR analysis of the ethyl α-azido-β-arylacrylates indicate that the condensation is stereospecific - only the Z-isomer could be detected. Solvent mediated thermal treatment of the meta-substituted ethyl α-azido-β- arylacrylates resulted in the formation of both the 5- and 7- substituted indoles - the 5-regioisomer being slightly favored over the 7-regioisomer. Analogous thermal treatment of (2Z, 2Z′)-diethyl 3,3′-(1,3- phenylene)bis(2-azidoacrylate) and (2Z, 2Z′)-diethyl 3,3′-(1,4- phenylene)bis(2-azidoacrylate) exclusively produced pyrroloindoles, diethyl 1,5-dihydropyrrolo[2,3-f]indole-2,6-dicarboxylate and diethyl 1,5-dihydropyrrolo[2,3-f]indole-2,6-dicarboxylate, respectively. Results are also reported which indicate that the α-azido-β-arylacrylates can be used in the subsequent Hemetsberger indolization process without prior purification.
Indol-2-yl ethanones as novel indoleamine 2,3-dioxygenase (IDO) inhibitors
Dolusic, Eduard,Larrieu, Pierre,Blanc, Sebastien,Sapunaric, Frederic,Norberg, Bernadette,Moineaux, Laurence,Colette, Delphine,Stroobant, Vincent,Pilotte, Luc,Colau, Didier,Ferain, Thierry,Fraser, Graeme,Galeni, Moreno,Frre, Jean-Marie,Masereel, Bernard,Van Den Eynde, Benoit,Wouters, Johan,Frederick, Raphael
, p. 1550 - 1561 (2011/03/22)
Indoleamine 2,3-dioxygenase (IDO) is a heme dioxygenase which has been shown to be involved in the pathological immune escape of diseases such as cancer. The synthesis and structure-activity relationships (SAR) of a novel series of IDO inhibitors based on the indol-2-yl ethanone scaffold is described. In vitro and in vivo biological activities have been evaluated, leading to compounds with IC50 values in the micromolar range in both tests. Introduction of small substituents in the 5- and 6-positions of the indole ring, indole N-methylation and variations of the aromatic side chain are all well tolerated. An iron coordinating group on the linker is a prerequisite for biological activity, thus corroborating the virtual screening results.
Dioxomolybdenum(VI)-catalyzed reductive cyclization of nitroaromatics. Synthesis of carbazoles and indoles
Sanz, Roberto,Escribano, Jaime,Pedrosa, Maria R.,Aguado, Rafael,Arnaiz, Francisco J.
, p. 713 - 718 (2008/02/09)
Reductive cyclization of nitrobiphenyls and nitrostyrenes to carbazoles and indoles, respectively, is carried out by triphenylphosphine under mild conditions catalyzed by a dichlorodioxomolybdenum(VI) complex. A one-pot procedure for the synthesis of regioselectively functionalized indoles has been developed from commercially available onitrobenzaldehydes and phosphoranes.
