Compound comprising structural units represented by formula (1) and formula (2): wherein X1, X2, X3 and X4 are the same or mutually different and represent a nitrogen atom or ═CH—; Y1 and Y2 are the same or mutually different and represent a sulfur atom, an oxygen atom, a selenium atom, —N(R1)— or —CR2═CR3—; R1, R2 and R3 are the same or mutually different and represent a hydrogen atom, a halogen atom, an amino group, a cyano group or a monovalent organic group; W1 and W3 are the same or mutually different and represent a halogen atom, a cyano group or a monovalent organic group; W2 and W4 are the same or mutually different and represent a hydrogen atom, a halogen atom, a cyano group or a monovalent organic group. The structural unit represented by formula (1) and the structural unit represented by formula (2) are not the same.