Patent ID: 7408072

Claim:
A heteropolycyclic compound represented by formula (1): wherein R 1 is a straight- or branched-chain C 1 -C 10 alkyl group, a substituted or unsubstituted C 5 -C 10 cycloalkyl group or a substituted or unsubstituted phenyl group; R 2 and R 3 are the same or different and are each a straight- or branched-chain C 1 -C 10 alkyl group, a substituted or unsubstituted C 5 -C 10 cycloalkyl group or a substituted or unsubstituted phenyl group, or R 2 and R 3 may be linked to each other to form, together with the nitrogen atom to which they are attached, a heterocyclic ring; R 4 and R 5 are each a hydrogen atom; X is a straight-chain C 1 -C 10 alkyl group, an —OCOR 6 group, or an —OR 6 group; R 6 is a hydrogen atom, a straight- or branched-chain C 1 -C 6 alkyl group or a substituted or unsubstituted C 5 -C 10 cycloalkyl group; and Z is —O— or —NR 6 — wherein R 6 is as defined above.