Leveling agent and electroplating composition for forming circuit pattern including the same

A leveling agent represented by Formula 1:

• wherein X1 and Y1 are each independently selected from the group consisting of C1-C10 alkyl groups, C6-C20 aryl groups, and C2-C20 heteroaryl groups, A1 is a single bond or is selected from the group consisting of oxygen (O), sulfur (S), carbonyl (C═O), NR1, C1-C10 alkylene groups, C6-C20 arylene groups, and C2-C20 heteroarylene groups, R1 is selected from the group consisting of hydrogen (H), C1-C10 alkyl groups, C6-C20 aryl groups, and C2-C20 heteroaryl groups, and n and m are each independently an integer from 0 to 10, with the proviso that at least one of n and m is 1 or more,
• or comprising at least one structural unit selected from the group consisting of those represented by Formulae 2 to 5:
• wherein A2 to A5 are each independently a single bond or is selected from the group consisting of oxygen (O), sulfur (S), NR2, carbonyl (C═O), C1-C10 alkylene groups, C6-C20 arylene groups, and C2-C20 heteroarylene groups, R2 is selected from the group consisting of hydrogen (H), C1-C10 alkyl groups, C6-C20 aryl groups, and C2-C20 heteroaryl groups, L1 and L2 are each independently selected from the group consisting of C1-C10 alkylene groups, C6-C20 arylene groups, and C2-C20 heteroarylene groups, each R3 is independently selected from the group consisting of hydrogen (H), C1-C10 alkyl groups, C6-C20 aryl groups, and C2-C20 heteroaryl groups, n and m are each independently an integer from 0 to 10, with the proviso that at least one of n and m is 1 or more, and each z is independently an integer from 1 to 10, with the proviso that the alkyl, aryl or heteroaryl group as each of X1 and Y1, the alkylene, arylene or heteroarylene group as A1, the alkylene, arylene or heteroarylene group as each of A2 to A5, the alkylene, arylene or heteroarylene group as each of L1 and L2, and the alkyl, aryl or heteroaryl group as each of R1 to R3 are each independently optionally substituted with one or more substituents selected from the group consisting of halogen groups, C1-C10 alkyl groups, C6-C20 aryl groups, and C2-C20 heteroaryl groups.