Abstract: The present invention relates to 4(3H)-pteridinones represented by the formula: ##STR1## in which X is an oxygen atom or a sulphur atom, Y is a hydrogen atom, a lower alkyl radical, especially a methyl radical, at the 6-position or a hydroxyl group at the 7-position, R.sub.1 is a hydrogen atom, a lower alkyl radical, a substituted or unsubstituted phenyl radical, a benzyl radical, a methoxymethyl group, an acetyl group, a 2-acetoxyethyl group or a 2,2,2-trifluoroethyl group and R.sub.2 is a hydrogen atom or a lower alkyl radical, especially a methyl radical.Application of these compounds as anti-allergic drugs.