| abstract |
A compound of the following formula ##STR1## wherein m is an integer of 1 to 3, R 1 and R 2 are the same or different and each is hydrogen atom or lower alkyl, and R 3 , R 4 , R 5 and R 6 are the same or different and each is hydroxy or a group of the formula ##STR2## (wherein n is 0 or 1, X is --NH-- or --O--, Y is alkylene, A is hydrogen atom, lower alkyl, lower alkoxy, halogen atom or trifluoromethyl, and B is alkyl or alkenyl), with the proviso that two or three of R 3 , R 4 , R 5 and R 6 are hydroxyl groups and that when two of them are hydroxyl groups, the cases where R 3 and R 5 are hydroxy, and R 4 and R 6 are hydroxy are excluded; a complex compound comprising said compound and a metallic atom; and a diagnostic agent containing said complex compound. The above compound is useful as a chelating agent and the complex compound comprising said compound and a metallic atom exhibits superior characteristics as a contrast medium for image diagnosis. |