183249-70-9Relevant academic research and scientific papers
Dipyrromethene-Triazolylidene Silver Complexes: Synthesis, Structure and Opportunities
Rago, Aurélie,Guérin, Charles,Framery, Eric,Jean-Gérard, Ludivine,Comby-Zerbino, Clothilde,Dugourd, Philippe,Andrioletti, Bruno
, p. 4409 - 4414 (2020)
The synthesis and characterization of unusual silver triazolylidene-containing dipyrromethene complexes are described. The carbene TAD-N3C-H obtained from its parent Triazole-Appended Dipyrromethene (TAD-N4) is an excellent ligand fo
The Dual Role of 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) in the Synthesis of Terminal Aryl- and Styryl-Acetylenes via Umpolung Reactivity
Morri, Ashok Kumar,Thummala, Yadagiri,Doddi, Venkata Ramana
supporting information, p. 4640 - 4643 (2015/09/28)
The dual role of the bicyclic amidine base 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was demonstrated in a synthesis of terminal aryl- and styryl-acetylenes. Mechanistically, a tandem process involving elimination/Umpolung/protonation occurs in a single step to generate terminal aryl- and styryl-acetylenes from geminal dibromoalkenes. The key to the success of this transformation lies in the organobase-mediated generation of the acetylide from the 1-bromoalkynes at room temperature. The unique characteristics of DBU as an inherently safer reagent make it an attractive alternative to previous systems wherein required pyrophoric reagents and nonambient temperatures remain unsolved issues. The procedure does not work for the synthesis of alkyl-acetylenes.
Regioselectively N-functionalised 14-membered azapyridinomacrocycles bearing trialkanoic acid side chains as ligands for lanthanide ions
Dioury, Fabienne,Sylvestre, Isabelle,Siaugue, Jean-Michel,Wintgens, Veronique,Ferroud, Clotilde,Favre-Reguillon, Alain,Foos, Jacques,Guy, Alain
, p. 4424 - 4436 (2007/10/03)
Four 14-membered azamacrocycles 2a-d, each containing a pyridine moiety and three acetic and/or propionic acid pendent arms, were prepared from regioselectively functionalised polyamines. The stability constants of the lanthanide complexes (La, Pr, Nd, Eu, Gd, Tb, Er, Yb, Lu) formed with the triacetic acid compound 2a were determined by spectroscopic methods (luminescence and/or UV/Vis spectroscopy). Other characteristics of the luminescent EuIII and TbIII complexes formed with the triacetic acid derivative 2a were also evaluated. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
Synthesis of new α-thiosialodendrimers and their binding properties to the sialic acid specific lectin from Limax flavus
Zanini, Diana,Roy, René
, p. 2088 - 2095 (2007/10/03)
Carbohydrate-protein binding interactions can be greatly amplified using the cluster or multivalent effect. In previous studies, sialylated multibranched L-lysine dendrimers were found to be potent inhibitors of the hemagglutination of human erythrocytes
Novel dendritic α-sialosides: Synthesis of glycodendrimers based on a 3,3′-iminobis(propylamine) core
Zanini, Diana,Roy, Rene
, p. 7348 - 7354 (2007/10/03)
The cluster or multivalent effect has been recognized as an effective means by which to increase binding interactions between carbohydrates and proteins. In fact, it has been demonstrated that sialylated multibranched L-lysine dendrimers were potent inhibitors of hemagglutination of human erythrocytes by Influenza viruses. In a continuation of these studies, the synthesis of novel glycodendrimers with even valencies from 2 to 16 and ending with equidistant thiosialoside residues is described. These symmetrical dendrimers were more readily characterized by standard NMR spectral techniques than previously reported nonsymmetrical dendrimers of this general type. The synthesis of the dendritic core was based on the regioselective protection of the primary amines of 3,3′-iminobis(propylamine) (4) using benzyl cyanoformate. The resulting secondary amine 5 was alkylated with tert-butyl bromoacetate to provide divalent core structure 6 with Cbz protected amines and acid protected tert-butyl ester. Sequential deprotection by trifluoroacetolysis or hydrogenation afforded acid 7 or diamine 8 as key precursors, respectively. The two fragments were coupled using HOBt/DIC strategy to provide Cbz-protected dendrimers with valencies of 2, 4, 8, and 16 in the first, second, third, and fourth generations, respectively, in reasonable to good yields (42-82%). Cbz-protected precursors were efficiently transformed into N-chloroacetylated dendrimers by hydrogenolysis and treatment of the resulting amines with chloroacetic anhydride (82-91%). N-Chloroacetylated dendrimers were then treated with an excess of 2-thiosialic acid derivative 3 to give fully protected sialodendrimers in 76-96% yields. Deprotection of sialodendrimers under Zemplen conditions followed by methyl ester saponification and purification by gel permeation chromatography afforded symmetrical dendritic α-thiosialosides 21, 23, 25, and 27 in fair yields (47-58%). These novel sialodendrimers, in keeping with their design, are currently being evaluated as inhibitors of human erythrocyte hemagglutination by Influenza viruses.
