| abstract |
The present invention provides a method for improving the existing synthesis method of compound (I), which has a long operation procedure, is troublesome, and obviously affects production cost, and enables its industrial production. A process for the preparation of 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid and its salts according to compound (I), comprising: A method comprising the following steps: a) carboxymethylation of a suitable precursor in water with haloacetic acid; and b) basic conditions by addition of the same base as that added in step a) Under hydrolysis reaction. [Selection figure] None |