The author of 《Protonation of 2,4-diaminopyrimidines. I. Dissociation constants and substituent effects》 were Roth, Barbara; Strelitz, Justina Z.. And the article was published in Journal of Organic Chemistry in 1969. Computed Properties of C7H10N4O2 The author mentioned the following in the article:
The basic dissociation constant of a series of approx. 70 2,4-diaminopyrimidines and condensed pyrimidine derivatives were obtained. The major effect of 5 substitution is inductive, but there is a greater resonance component than can be accounted for by correlation with Hammett σm constant The effect of 6 substitution, on the other hand, is almost completely inductive. Similar relations were found with 4-amino-6-substituted pyrimidines. In some cases H bonding renders such correlations imprecise. Dissociation constant of 4-substituted pyrimidines can be correlated with σp constant, but 2-substituted derivatives appear to have a considerately greater inductive component. The shifts in uv maximum of 2,4-diamino-6-substituted, but not 5-substituted, pyrimidines had a dependence on the + R or -R character of the substituents. Ion pair formation between certain diaminopyrimidines and divalent ions in aqueous solution was postulated on the basis of uv studies. After reading the article, we found that the author used Ethyl 2,4-diaminopyrimidine-5-carboxylate(cas: 15400-54-1Computed Properties of C7H10N4O2)
Ethyl 2,4-diaminopyrimidine-5-carboxylate(cas: 15400-54-1) belongs to anime. The reaction of alkyl halides, R―X, where X is a halogen, or analogous reagents with ammonia (or amines) is useful with certain compounds. Not all alkyl halides are effective reagents; the reaction is sluggish with secondary alkyl groups and fails with tertiary ones. Its usefulness is largely confined to primary alkyl halides (those having two hydrogen atoms on the reacting site).Computed Properties of C7H10N4O2
Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia