The method of claim 5, wherein said substituent of the group represented by R.sup.2 is a group represented by the following Formula CU-II: ##STR10## wherein J is an oxygen atom or a sulfur atom; R.sup.3 is an alkenyl group; R.sup.4 is asubstituent and K is an integer of 0 to 4 and 1 is 0 or 1.8.