A method for preparing the compound of Formula (I) which comprises subjecting a compound of Formula (II): ##STR90## wherein ring A and R3 are defined as above, and a compound of Formula (III): R1 OC--C.tbd.C--R2 (III) wherein R1 is defined as above, and R2 is a group represented by the formula --COOR' (wherein R' is a lower alkyl or aralkyl group which is optionally s