5-Substituted 4-hydroxy-2-methylpyrimidines

In the 1880s, Pinner found that the amidine derivative 2 reacted with acetoacetic ester (4) to furnish 2-substituted-6-hydroxy-4-methylpyrimidine 5. The condensation of amidine derivative 2 with other (l-keto esters, malonic esters, and (l-diketones proceeded similarly (see the following pages for examples). ... [Pg.536]

Substituted-4-hydroxy-6-methylpyrimidines are formylated in the 5-position when the 2-substituent (e.g. NH2, OH) is sufficiently electron releasing. The related 4-mercapto compounds gave only the ortho-thio-esters. ... [Pg.76]

The condensation of diethyl formylsuccinate with amidines is an established p3mmidine synthesis (16, 714). Extended to 1-substituted biguanides, the reaction yields 2-guanidino-4-hydroxy-5-carbethoxy-methylpyrimidines as follows (684) ... [Pg.55]

Tertiary amines boost the reactivity of POCl3 in the substitution of hydroxy pyrimidines774. Thus 6-methyluracil is reacted with POCl3 in the presence of tri- -propylamine to yield 2,4-dichloro-6-methylpyrimidine, while triethylamine gives some amination products as well (equation 105)775. [Pg.579]

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