Reactivity of. toward nitrogen nucleophiles

Naphthalen-1,4,imines, 16, 87 Naphthyridines, 11, 124 reactivity of, toward nitrogen nucleophiles, 33, 95... 

We have been unable to demonstrate any reaction between cyanatryn -oxide and DNA in vitro or between cyanatryn and liver DNA in vivo(2). Three hours after oral doses of []cyanatryn giving about 2 (1.98 and 2.41) yg of cyanatryn equivalents per g of liver, the perfused livers were removed, pooled and used to prepare protein, RNA and DNA fractions(14). Values expressed as yg of cyanatryn per g of pooled liver were total, 2.19 protein, 0.29 RNA fractions, 0.002 DNA fraction, not detectable. Radiochemical in the combusted sample of DNA was not detectable, i.e. less than 1 dpm/mg. This value is equivalent to 1 mol of triazine to 10 mol of guanine. Cyanatryn and its -oxide apparently possess low reactivity towards nitrogen nucleophiles. 

The nucleophilic reactivity of the nitrogen atoms in thioureas towards carbonyl compounds has been further exemplified by some recently described addition and addition-elimination reactions of thioureas with aldehydes. The same reactivity also played an important part in recent syntheses of heterocyclic compounds containing the thioureido-grouping. ... 

As is broadly true for aromatic compounds, the a- or benzylic position of alkyl substituents exhibits special reactivity. This includes susceptibility to radical reactions, because of the. stabilization provided the radical intermediates. In indole derivatives, the reactivity of a-substituents towards nucleophilic substitution is greatly enhanced by participation of the indole nitrogen. This effect is strongest at C3, but is also present at C2 and to some extent in the carbocyclic ring. The effect is enhanced by N-deprotonation. 

Arylamines contain two functional groups the amine group and the aromatic ring they are difunctional compounds The reactivity of the amine group is affected by its aryl substituent and the reactivity of the ring is affected by its amine substituent The same electron delocalization that reduces the basicity and the nucleophilicity of an arylamme nitrogen increases the electron density in the aromatic ring and makes arylamines extremely reactive toward electrophilic aromatic substitution... 

Polyurethane Formation. The key to the manufacture of polyurethanes is the unique reactivity of the heterocumulene groups in diisocyanates toward nucleophilic additions. The polarization of the isocyanate group enhances the addition across the carbon—nitrogen double bond, which allows rapid formation of addition polymers from diisocyanates and macroglycols. 

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