Maleic Anhydrides로부터 Alkoxyallylthiopyridazines 유도체의 효과적 합성

Abstract

Alkoxyallylthiopyridazine derivatives which exhibit superior effect for the treatment of hepatic diseaseswere synthesized from maleic anhydrides. The reaction of maleic anhydrides with hydrazine monohydrate in aq HCl atreflux afforded dihydroxypyridazines, which were transformed to dichloropyridazines with phosphorus oxychloride. Thesubstitution of the first chlorine atom in dichloropyridazines proceeded selectively with alcoholic sodium alkoxides inTHF to afford alkoxychloropyridazines, which were converted to alkoxyallylthiopyridazines with lithium 2-propene-1-thiolate in high yields.