PROCEDE POUR LA PREPARATION DE DERIVES DE LA PYRAZINE

摘要

The present invention relates to the preparation of pyrazine derivatives of the formula <IMAGE> in which R1 is hydrogen or lower alkyl; R2 is hydroxyl, alkoxy having 1 to 6 C atoms or a group of the formula <IMAGE> in which R3 and R4 independently of one another represent hydrogen or alkyl having 1 to 6 C atoms, and n is 1 or zero. Compounds of the formula (I) in which n is zero are prepared starting from diaminomaleonitrile of the formula <IMAGE> The diaminomaleonitrile and a compound of the formula CHOCOR1 are subjected to a condensation reaction, and the resulting compounds are reacted with an acid.