A compound represented by formula (1)(see formula 1)or a pharmacologically acceptable salt thereof is provided.(In formula (1), R1 is a hydrogen atom, etc.; L is a singlebond, -O-, etc.; R2 is phenyl, etc.; X is a carbon atom or anitrogen atom; and R3, R4, R5a, R5b, R6, and R7 each is asubstituted or unsubstituted alkyl, etc.) Compounds of theinvention may be used for inhibition of SNS.