A novel purine derivative exhibiting an effect to control inflammatory symptoms characteristic to nephritis and a medicine comprising this compound as an effective ingredient are provided. The compound is represented by the following general formula (I), wherein R1 is a hydrocarbon group having 17 or less carbon atoms and R2 is a hydrocarbon group having 16 or less carbon atoms, wherein one or more CH2 g roups in the hydrocarbon group which 7013 do not directly bind with the carbon atom at 2 or 7 position of the purine ring replaced are by carbonyl groups, sulfonyl groups, O, or S and/or one or more CH groups in the hydrocarbon group which do not directly bind with the carbon atom at 2 or 7 position of the purine ring are replaced by N, C-halogen, or C—C≡N, or a pharmaceutically acceptable salt thereof.