Patent ID: 6906083

Claim:
A compound, a salt thereof, or a hydrate of said compound or salt thereof, said compound represented by the formula: wherein R 2 of formula (I) represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, an optionally substituted C 2-6 alkenyl group or an optionally substituted C 2-6 alkynyl group, a salt thereof, or a hydrate of said compound or salt thereof; R 1 is a group selected from the group of formulae consisting of R 3 , R 4 , R 5 and R 6 are the same as or different from each other and each represents a hydrogen atom, a halogen atom, a hydroxyl group, an optionally substituted hydrocarbon group, an optionally substituted C 1-6 alkoxy group, a C 1-6 acyl group, a nitro group, an optionally substituted amino group, an optionally substituted amide group, a mercapto group or a C 1-6 thioalkoxy group; and m is 0 or an integer from 1 to 6.