Synthesis of carbon‐14 labelled (3‐{[(Z)‐5‐chloro‐2,3‐dihydro‐3‐(hydroxy‐2‐thienylmethylene)‐2‐oxo‐1
H
‐indol‐1‐yle]carbonylamino}propyl)trimethylammonium chloride, a potential cartilage‐targeted antirheumatic drug
摘要:
A [C-14]-labelled form of (3-{[(Z)-5-chloro-2,3-dihydro-3-(hydroxy-2-thienylmethylene)-2-oxo-1H-indol-1-yle]carbonylamino}propyl)trimethylammonium chloride, a potential cartilage-targeted antirheumatic drug, was required for pharmacokinetic studies. This compound, labelled with [C-14] located in the C-3 methylene position, was prepared in four steps starting from N-[3-(dimethylamino)propyl]-5-chloro-2,3-dihydro-2-oxo-1H-indole-1-carboxamide and 2-thiophene-[C-14]carbonyl chloride, previously synthesized by a two-step sequence from barium [C-14]-carbonate and 2-thienyllithium. The desired product was obtained with a specific activity of 359 MBq/mmol (9.7 mCi/mmol). The overall radiochemical yield was 50% based on barium [C-14]-carbonate.