(9) an intermediate represented by the following formula VIII for synthesizing the amide derivative of formula I: ##STR8## where in the formula VIII, when R9 is a hydrogen atom, R10 represents an alkanoyl group having 1 to 8 carbon atoms of a carbon chain that may have a branched chain, a haloalkanoyl group having 1 to 8 carbon atoms of a carbon chain that may have a branched chain, a phenylalkano