Compounds represented by the following general formula: [wherein X1, X2, X3 and X4 each independently represent a single bond, C1-6 alkylene, etc.; A2 represents optionally substituted phenyl, etc.; A1 represents an optionally substituted 5- to 7-membered heterocyclic group containing —C(=Q1)- (wherein Q1 represents oxygen, sulfur or ═N—R11 (wherein R11 represents hydrogen or C1-6 alkyl)) and nitrogen, etc.; and Z1 represents piperidin-diyl, etc.], salts thereof and hydrates of the foregoing.