alternatively r a and r b x 1 and r a or r b x 3 and r a or r b or q 1 and r a or r b may combine with each other to form a cyclic structure z 1 and z 2 each represents a n valent connecting group having at least 6 carbon atoms preferably at least 7 carbon atoms in which the n 39 s connecting parts are all hetero atoms n represents an integer of from 2 to 6 and preferably an integer of from 3 to 6 the hetero atoms at the n 39 s connecting parts of z 1 and z 2 are selected from an oxygen atom a sulfur atom a nitrogen atom and a phosphorus atom and preferably forms a substituted oxy group a substituted thio group an amino group a substituted amino group or a heterocyclic group that is connected through a hetero atom included therein the n 39 s connecting parts of z 2 contain more preferably a connecting structure of u2014 oco u2014 the most preferred specific examples of z 1 and z 2 include connecting structures shown in specific examples of the compounds having a structure represented by.