Patent ID: 8354529

Claim:
A compound of formula (1) or a salt thereof, wherein X is (NR 4 ), R 1 is a group of formula (2-2), where R 5 is a m-valent hydrocarbon, m is an integer of from 2 to 8, d is an integer of from 1 to 6, R 2 is a hydrogen atom or an alkyl group having from 1 to 9 carbon atoms, R 3 is a hydrogen atom, an alkyl group having from 1 to 9 carbon atoms, an alkoxy group having from 1 to 9 carbon atoms or an acyl group having from 2 to 9 carbon atoms, R 4 is a hydrogen atom or an alkyl group having from 1 to 9 carbon atoms and n is an integer of from 4 to 16.