(3) A1 in the above-mentioned Chemical Formula 5-1 is a characteristic group represented by the following Chemical Formula 5-2 or Chemical Formula 5-3. (k is an integer of 1 to 18 inclusive, m and n are an integer of 0 to 37 inclusive, m+n=2k+1, p is an integer of 0 or 1, and q is an integer of 0 or 1.) (k is an integer of 1 to 18 inclusive, m and n are an integer of 0 to 37 inclusive, m+n=2k+1, a