Cyclic nitrogen

Compounds with one cychc nitrogen and three cychc oxygen atoms, etc. Compounds with two cyclic nitrogen and one cychc oxygen atom. 

XXI XXI, 1st 1935 3103-3241 One Cyclic Nitrogen (continued). Hydroxy compounds Atropine, 27. 

XXIII xxin, 1st 1936 3458-3554 Two Cyclic Nitrogens. Stem nuclei Piperazine, 4. Diazo-... 

XXIV XXIV, 1st 1936 3555-3633 Two Cyclic Nitrogens (continued). j Carbonyl compounds Antipyrin, 27. 

XXVI 1937 3794-4187 Three Cyclic Nitrogens to Eight Cyclic... 

XXVI, 2nd 1965 3794-4187 Four cyclic nitrogens, 321 Xanthine, 447. Caffeine, 461. Uric acid, 613. 

Ultraviolet spectra of A-4-thiazoline-2-thione in 10 A HCl show that protonation occurs on the exocyclic sulfur rather than on the cyclic nitrogen or on the enamine-like Co-position (56). 

In 1880, Liebermann and Voltzkow (40), and then Voltzkow (41), condensing chloroacetic acid with both ethyl N-phenylthiocarbamate and p-tolylisothiocyanate obtained homologous compounds to which they attributed formulas 40 and 41, whereas their structure probably derives from that of 38 by substituting an aryl group on the cyclic nitrogen. 

In still other cases, the product of reaction of an electrophile with an aminoazole is from electrophilic attack at a ring carbon. This is electrophilic substitution and is the general result of nitration and halogenation (see Section 4.02.1.4). In such cases, reactions at both cyclic nitrogen and at an amino group are reversible. 

The mono- and some di-aminoacridines, 6- and 7-aminoquin-oline, and 3-aminopyridine form monocations in which protonation occurs preferentially at the ring nitrogen atom. However, ultraviolet spectral data show that 1,9-diaminoacridine (237, R = NH2) undergoes proton addition on the amino groups in preference to the cyclic nitrogen atom, whereas l-amino-9-methylacridine (237, R = Me) is monoprotonated principally at the amino group in ethanol... 

Signals of the Cyclic Nitrogens in the NMR Spectra oe 1, 2,4-Triazines IN DMSO- tj (McN02 as the Standard) in Comparison (A ) with Those oethe Parent 1, 2,4-Triazines [84SA(A)637]... 

Compounds with one cyclic nitrogen and one cyclic oxygen atom. 

Compounds with two cyclic nitrogen and two cyclic oxygen atoms. 

XX XX, 1st Supplement (combined with Volumes XXI and XXII) XX, 2nd Supplement 1935 3032-3102 One Cyclic Nitrogen. Piperidine, 6. Pyrrole, 159. Pyridine, 181. Indole, 304. Quinoline, 339. Isoquinoline, 380. Carbazole, 433. Acridine, 459. 

XXVII XXVII, 1st i Supplement 1937 4199-4720 One Cyclic Oxygen and One Cyclic Nitrogen. 

The azaallyl anions 85.11-85.17 derived from cyclic nitrogen heterocycles generally react with 6 to afford the corresponding bridgehead nitrogen heterocycles. Some of the examples studied by our group are described below. 

Analysis of the published data on the stereodynamics of cyclic nitrogen compounds (510) as well as the results of studies of the stereodynamics of BENA... 

As acesulfame K contains cyclic nitrogen, a nitrosation study was carried out which did not show any nitrosation under normal use conditions. In model reactions with food constituents or substances modelling groups of food constituents, no reactions of acesulfame K with these components was detected.7... 

Fig. 5. Chiral cyclic nitrogen nucleophiles 95-100 as potential ammonia equivalents...

Reduction of diazetidine N,N-dioxides in a two-step process is the other common method used to generate cyclic nitrogen-nitrogen double bonds (Scheme 49) (75JOC1409). 

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