Pyrrolopyrimidines, their production and use

A compound of the formula (I): wherein the ring Ⓐ is a pyrrole ring which may be hydrogenated, X is an amino group, a hydroxyl group or a mercapto group, Y is a hydrogen atom or a hydroxyl group, -COOR¹ and -COOR² may be the same or different and are a carboxyl group which may be esterified, -Ⓑ- is a divalent heterocyclic group or a lower alkylene group each of which may be substituted, and Z is a straight C₂₋₄ divalent group which may be substituted, or its salt, a method for the production of the same and an antitumor agent containing the same.