[Problem]Provided is a compound which is useful as an active ingredient for a pharmaceutical having a PKCθ inhibition activity, particularly a pharmaceutical composition for inhibiting acute rejection occurring in transplantation.[Means for Solution]The present inventors have conducted extensive studies on a compound having a PKCθ inhibition activity, and as a result, they have found that a compound having a structure such as aralkyl and the like on an amino group at the 2-position and also having a structure such as an adamantylalkyl group and the like on an amino group at the 4-position of 2,4-diaminopyrimidine, or a salt thereof has an excellent PKCθ inhibition activity, thereby completing the present invention. The 2,4-diaminopyrimidine compound of the present invention can be used as a PKCθ inhibitor or an inhibitor of acute rejection occurring in transplantation.
