A microscale synthesis of a promising radiolabelled antitumor drug: Cis‐1,1‐cyclobutanedicarboxylato (2R)‐2‐methyl‐1,4‐butanediamine platinum(II), NK121

A promising antitumor drug, cis‐1,1‐cyclobutane‐dicarboxylato (2R)‐2‐methyl‐1,4‐butanediamine platinum(II), NK121, was synthesized from radionuclides of platinum such as ^193mPt, ^195mPt and ¹⁹¹Pt which were produced by neutron irradiation of enriched ¹⁹²Pt. The overall yield was 38.6% in a synthesis time of 10 hours. The radioactivities present in 8.39 mg of NK121 were 115.3 μCi as ^193mPt, 29.9 μCi as ¹⁹⁷Pt, 22.0 μCi as ^195mPt, and 4.8 μCi as ¹⁹¹Pt at the end of synthesis. The specific activity of the NK121 was 13.7 μCi (^193mPt)/mg NK121 at the end of synthesis. The radiochemical purity of NK121 was typically 99 %. HPLC analyses confirmed that NK121 was in an adequate chemical purity and suitable for animal experimentation.