The present invention provides a compound represented by the following formula [1] or a pharmaceutically acceptable salt thereof which has an excellent NHE3 inhibitory effect: A-Y  [1] wherein A represents a structure represented by the following formula [2]: wherein R11 and R12 each represent a halogen atom or others as described herein, R2 represents C1-6 alkyl or others as described herein, ring E represents triazole, tetrazole, pyrimidine, or others as described herein, R31 and R32 each represent a hydrogen atom, C1-6 alkyl, C1-6 alkoxy, or others as described herein, and W represents a single bond, the formula —NH—, the formula —O—, or the formula —CONH—, and Y represents a hydrogen atom or a structure selected from