" (shown below) inclusive of a hetero atom (e.g., oxygen, nitrogen, sulfurand halogen) or an alkyl or aryl containing such a group of atoms.As the group of atoms inclusive of a hetero atom, mention may be made of halogen atoms such as fluorine, chlorine and bromine, hydroxyl groups, alkoxy groups such as methoxy, ethoxy, butoxy and tert-butoxy, aryloxy groups such as phenyloxy,formyl groups, alkylc" . . . . .