104. Über die säurekatalysierte Hydrolyse von Diazoketonen II Der säurekatalysierte H-D-Austausch

Two-stage photosensitive label for antibody combining sites

“…DNP-glycine diazoketone was identified by the infrared diazo stretching band at 2115 cm-1 (Foffani et al, 1960). The nuclear magnetic resonance spectrum (Varían A-60) in fully deuterated acetone showed all the peaks in the DNP-glycine spectrum, and in addition a broad amino proton triplet at 2.7 ppm below tetramethylsilane and a diazomethyl proton singlet at 6.1 ppm (Dahn et al, 1963). The high-resolution mass spectrum contained an ion peak at 265.0444 mass units (C9H7N5O5, 265.0447) which corresponds to the molecular ion for DNPglycine diazoketone, and one of equal intensity at 237.0383 (CgH7N305, 237.0385) which is consistent with either DNPglycine carbene or DNP-glycine ketene.…”

vic‐Tricarbonyl Compounds of Quinolines: Analogues of Ninhydrin: A Short Review

“…A classical method for the synthesis of quinisatin was demonstrated by Dahn and Donzel in 1967 . Nitrosation of 4‐hydroxyquinolin‐2(1 H )‐one ( 5a ) yielded 1,2,3,4‐tetrahydroquinoline‐2,3,4‐trione‐3‐oxime ( 6 ), which upon reduction gave 1,2‐dihydro‐3,4‐dihydroxyquinolin‐2‐one ( 7 ).…”

“…Nitrosation of 4‐hydroxyquinolin‐2(1 H )‐one ( 5a ) yielded 1,2,3,4‐tetrahydroquinoline‐2,3,4‐trione‐3‐oxime ( 6 ), which upon reduction gave 1,2‐dihydro‐3,4‐dihydroxyquinolin‐2‐one ( 7 ). 1,2,3,4‐Tetrahydroquinoline‐2,3,4‐trione (quinisatin) ( 4a ) was obtained by the oxidation of 7 with HIO 3 (Scheme ) . They noted that basic hydrolysis of quinisatin ( 4a ) gave isatin ( 8 ) and 1,2‐dihydro‐3,4‐dihydroxyquinolin‐2‐one ( 7 ) probably through the formation of 2,3‐dihydroxyindole, which reduced quinisatin ( 4a ) to 7 and itself oxidized to isatin ( 8 ) (Scheme ) .…”

Echanges isotopiques d'hydrogène T‐H, T‐D, D‐H et H‐D de la diazoacétone et du diazoacétaldéhyde: Vitesse de protonation et effets isotopiques. Communication préliminaire

“…I1 serait donc trks intkressant de comparer les &apes de protonation du carbone en prCCquilibre ctrapide,, avec les protonations ctlentesa du type A -S E~. Cette comparaison s'est avCrCe possible [5] du fait que la vitesse de protonation du prCCquilibre se retrouve dans les rkactions d'kchange isotopique de I'hydrogkne, accessibles A la mesure par des moyens cinCtiques ordinaires.…”