Patent ID: 8076478

Claim:
A compound of formula (1) or a salt thereof, wherein X represents N(R 4 ) or an oxygen atom, R 1 is a group of formula (2-1), Y is CH or a nitrogen atom, a, b and c each independently are an integer of from 1 to 6, provided that R 4 may not be R 2 represents a hydrogen atom or an alkyl group having from 1 to 9 carbon atoms, R 3 represents 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 represents a hydrogen atom or an alkyl group having from 1 to 9 carbon atoms and n is 3.