Synthese d'une pyridazine d'interet therapeutique, marquee au carbone 14: Dichlorhydrate de morpholinoethylamino‐3 methyl‐4 phenyl‐6 pyridazine ¹⁴C‐6 (30,038 CB)

Benzoyl chloride‐7 14 C is condensed with tris(trimethylsilyl) 1‐lithio‐1,1,2 propane tricarboxylate, which after hydrolysis gives rise to a 66% yield of 2‐methyl‐3‐(benzoyl‐7‐ 14 C) propionic acid. After cyclisation with hydrazine, followed by treatment with bromine in acetic acid, 3‐hydroxy‐4‐methyl‐6‐phenyl pyndazine 6‐ 14 C is secured in a 77% yield. This hydroxypyridazine treated with POCl 3 gave a 90% yield of 90 % pure 4‐methyl‐6‐phenyl‐3‐chloropyndazine 6‐ 14 C; The latter treated with 2‐morpholino‐1‐aminoethane in presence of sodium iodide has given 3‐morpholinoethylamino 4‐methyl 6‐phenylpyndazine 6‐ 14 C. The overall yield based on barium carbonate 14 C is 16.7 % (specific activity 18.5 mCi/mMole).