Compounds represented by general formula (I), pharmaceutically acceptable acid addition salts thereof, or hydrates of the same; drugs containing these compounds; medicinal compositions containing these compounds together with pharmaceutically acceptable carriers; and 2-amino-2-(2-(4-(1-hydroxy-5-phenylpentyl)phenyl)ethyl)propane-1,3-diol or 2-amino-2-(2-(4-formylphenyl)ethyl)-propane-1,3-diol optionally protected at the amino and/or hydroxy group or salts thereof, each useful as an intermediate in synthesizing the above compounds. In said formula, R?1, R2, R3 and R4¿ represent each hydrogen or acyl. Because of having little toxicity, high safety and excellent immunosuppressive effects, these compounds are useful as preventives or depressants for rejection reactions in organ or bone marrow transplantations and preventives or remedies for various autoimmune diseases, various allergic diseases, etc.