Summary: | 碩士 === 中原大學 === 化學研究所 === 90 ===
DTPA (diethylenetriamine pentaacetic acid) is a useful bifunctional chelator which can be conjugated to a peptide, a protein or other target-seeking compounds and, in the mean time, chelated to a radioisotope. The resulting compounds can be used as radiopharmaceuticals. In the conjugation of DTPA to target-seeking compounds, for the purpose of avoiding the occurrence of bis-conjugated by-products which require tedious separation, mono-active DTPA has been developed. However, the current synthesis of mono-active DTPA takes six steps, which is lengthy and high cost. In this thesis, a two steps process to accomplish this synthesis was reported. Therein, a penta-ester of DTPA is prepared followed by a selective hydrolysis to obtain mono-active DTPA. The total yields are 55.5% and 32.9% for R = ethyl and t-butyl, respectively.
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