The present invention provides a novel piperidine derivative and a tachykinin receptor antagonist containing same, as well as a compound represented by the formula:
wherein R
1
is carbamoylmethyl, methylsulfonylethylcarbonyl and the like; R
2
is methyl or cyclopropyl; R
3
is a hydrogen atom or methyl; R
4
is a chlorine atom or trifluoromethyl; R
5
is a chlorine atom or trifluoromethyl; and a group represented by the formula:
is a group represented by the formula:
wherein R
6
is a hydrogen atom, methyl, ethyl or isopropyl; R
7
is a hydrogen atom, methyl or a chlorine atom; and R
8
is a hydrogen atom, a fluorine atom, a chlorine atom or methyl; or 3-methylthiophen-2-yl, and a salt thereof.