| abstract |
Compounds represented by general formula (1) or salts thereof which are useful as the active ingredient of drugs for preventing and/or treating irritable bowel syndrome, systemic functional disorder of digestive tract or diarrhea, wherein R1 represents halogeno; R2 represents hydrogen or lower alkyl; and R3 represents hydrogen, lower alkyl, lower alkoxy, hydroxy(lower alkyl), halogeno or amino optionally having a substituent selected from the group consisting of lower alkyl, lower alkenyl, lower alkylcarbony and amino-protective groups. |