Compounds represented by formula (1-1) or salts thereof. [In the formula, b represents an integer from 1 to 5, and Z is a group represented by formula (Z-1), formula (Z-2), formula (Z-3), formula (Za-1), formula (Za-2), formula (Za-3), formula (Za-4), or formula (Za-5)].本發明係一種化合物或其鹽,該化合物以式(1-1)表示: [式中,b表示1~5之整數,Z為式(Z-1)、式(Z-2)、式(Z-3)、式(Za-1)、式(Za-2)、式(Za-3)、式(Za-4)或式(Za-5)所表示之基]。