1,4,7,10-Dota 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid 1,4,7,10-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid 1,4,7,10-tetraazacyclododecane- 1,4,7,10-tetraacetic acid 60239-18-1 Dota acid