PROBLEM TO BE SOLVED : To provide compounds useful for treating and/or preventing clinical conditions including respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD). SOLUTION : The present invention provides (2S)-N-[(1S)-1-cyano-2-phenylethyl]-1, 4-oxazepane-2-carboxamide compounds, represented by a following formula. [R1 is a phenyl group, and is unsubstituted, or substituted with F, Cl, an azetidine ring, a pyrrolidine ring, a piperidine ring-containing heterocycle or the like]. SELECTED DRAWING : None COPYRIGHT : (C)2019, JPO&INPIT