. "The norbornene structure compound represented by the formula (2) ##STR3## wherein l, m and n are integers of 0???l???3, 0???m???8 and 1???n???3, respectively, and each of R1 to R6 is a hydrogen atom or a hydrocarbon residue having 1 to 3 carbon atoms and R6 may form a ring with R4 or R5, has an active double bond of norbornene ring and can be converted into useful medicines or agricultural chemica" . . .