Heterocyclic Janus kinase 3 inhibitor

The present invention has an excellent JAK3 inhibitory activity, autoimmune diseases, inflammatory diseases, including allergic diseases, to provide compounds useful as an active ingredient of a therapeutic and / or prophylactic agent for various immune diseases. The compounds of the present invention, since it has an inhibitory activity against JAK3, disease (example caused by undesirable cytokine signal transduction, rejection in vivo transplantation, autoimmune diseases, multiple sclerosis, arthritis, psoriasis, asthma, atopy sex dermatitis, Alzheimer's disease, atherosclerosis), or diseases (e.g. caused by cytokine signaling abnormalities, cancer, to be useful as an active ingredient of a therapeutic agent or prophylactic agent for leukemia) was confirmed.