46 research outputs found
A straightforward synthesis of indazolo[3,2-a]isoquinolin-6-amines
4-Substituted 1-bromoisoquinolin-3-amines were subjected to Suzuki coupling with o-nitrophenylboronic acid to yield 1-(2-nitrophenyl) isoquinolinamines, which participated in Cadogan cyclization with triethyl phosphite under microwave irradiation in a sealed vial to yield fluorescent indazolo[3,2-a] isoquinolin-6-amines. The new compounds were also functionalized by transformation of the amino group. © 2013 Elsevier Ltd. All rights reserved
Cyclopropanation of carbon-carbon double bonds in ring d of ergot alkaloids
Some ergot alkaloid derivatives containing a double bond in ring D have been reacted with diazomethane/palladium diacetate reagent to result in formation of a fused cyclopropane ring. This procedure proved to be generally applicable for cyclopropanation of Ergot alkaloids
Effect of enzymatic modification on the biological activity and nutritive value of cow and buffalo casein
Buffalo and cow milk caseins were submitted to hydrolysis either with á -chymotrypsin or with pepsin. Enzymatic peptide modification (EPM) was carried out by using L-methionine ethyl ester in the reaction mixture. As catalyst, á -chymotrypsin or pepsin was used. The incorporation of methionine in to the peptide chains in the presence of á -chymotrypsin showed an optimum value at 0.14 g Met added to the reaction mixture/1 g hydrolysate in both cases. In the case of pepsin used as catalyst, the optimal Met-enrichment was at 0.14 g Met added to the reaction mixture/1 g buffalo casein hydrolysate and at 0.34 g Met/1 g cow casein hydrolysate. The covalent nature of the amino acid incorporation was confirmed by SDS - polyacryl amide gel electrophoresis in the presence of urea. Electrophoretic patterns of the products indicate that transpeptidation plays an essential role in the EPM reaction. Antigenic character of the EPM- products was investigated in vitro by competitive indirect ELISA. Enzymatic peptide modification with methionine enrichment seems to be an efficient method for the reduction of the antigenic/potential allergenic character and for the improvement of the nutritive value of buffalo and cow milk caseins
Unexpected valence bond isomerization of [1,2,4]triazolo[3,4-c][1,2,4]benzotriazines under flash vacuum pyrolytic (fvp) conditions
Flash vacuum pyrolysis (fvp) of some substituted [1,2,4]triazolo[3,4-c][1,2,4]benzotriazine derivatives (1a–d) has been studied between 450 and 600 8C. The only transformation observed up to 525 8C was the unexpected valence bond isomerization of the angularly fused starting compounds to the isomeric linearly fused [1,2,4]triazolo[4,3-b][1,2,4]benzotriazine derivatives (9a–d), whereas at higher temperatures fragmentation products such as aromatic nitriles were also formed. Kinetic measurements revealed negative entropies of activation in the isomerization process, which suggest a concerted ring closure reaction to an intermediate antiaromatic diazirine. Reversibiblity of the title isomerization reaction was also proved by FVP experiments.Fil: Peláez, Walter José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Yranzo, Gloria Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Gróf, Csilla. Hungarian Academy of Sciences; HungríaFil: Riedl, Zsuzsanna. Hungarian Academy of Sciences; HungríaFil: Hajós, György. Hungarian Academy of Sciences; Hungrí
Az üzleti hírszerzés szerepe a vállalatirányításban
A szerzők az üzleti hírszerzés speciális feladatait elemzik dolgozatukban. Egy olyan új tevékenységet mutatnak be, amely már hazánkban is elfogadottá, mi több: szakmává vált. A Budapesti Műszaki és Gazdaságtudományi Egyetem Mérnöktovábbképző Intézete megkezdte a téma menedzsereknek szóló jellemzőinek oktatást. A cikk írói szerzőként jegyzik az Üzleti hírszerzés című tankönyvet, amely Magyarországon az első ilyen témájú összefoglaló mű