A compound represented by Formula (1): each of L1 and L2 independently represents an
alkyl group having from 1 to 20 carbon atoms, an
alkoxy group having from 1 to 20 carbon atoms, NH2, NHR3, NR3R4, an ester group, a carboxy group, an
amide group, a cyano group, a nitro group, a
halogen atom, an
acyl group, CF3, O(CH2)1OCH3, a
carbamate group, or an
aryl group. 1 represents 1 or 2. Each of R1 and R2 independently represents a
divalent hydrocarbon group having from 1 to 10 carbon atoms, at least one
hydrogen atom of the
divalent hydrocarbon group is optionally substituted with an
alkyl group, an
aryl group, an ester group, a carboxy group, an
amide group, a cyano group, a nitro group, a
halogen atom, an
acyl group, CF3, O(CH2)1OCH3, a
carbamate group, or an
alkoxy group, each of R3 and R4 independently represents an
alkyl group, an
aryl group, an
acyl group, an ester group, an alkylsulfonyl group, or an arylsulfonyl group, each of R5 and R6 independently represents a
hydrogen atom, an alkyl group having from 1 to 20 carbon atoms, or an aryl group, and n+m≥1.