5α-pregn-20-ene-20-carboxamides were synthesized from the widely accessible 3β-acetoxy-pregn-5,16-dien-20-one (PDA) using selective hydrogenation, hydrazine and iodoalkene formation, as well as palladium-catalysed aminocarbonylation. The 20-iodo-20-ene derivatives, obtained from the corresponding 20-keto derivatives via their hydrazones, served as substrates. 23 new 20-carboxamides were obtained using various N-nucleophiles
由广泛可得的3β-乙酰氧基-pregn-5,16-合成20-羧酰胺基孕烯衍
生物,例如3β-乙酰氧基-5α-pregn-20-ene-20-羧酰胺和5α-pregn-20-ene-20-羧酰胺。 Dien-20-one(
PDA)使用选择性加氢,
肼和
碘代烯烃的形成,以及
钯催化的
氨基羰基化。通过相应的20酮从相应的20-酮衍
生物获得的20-
碘-20-烯衍
生物用作底物。使用各种氮素获得了23种新的20-羧酰胺-亲核试剂,范围从简单的
伯胺到
α-氨基酸酯。这种方法的新颖之处在于应用轻度,中度或高产率的反应来获得原本难以获得的具有药学重要性的甾族20-羧酰胺。换句话说,代替了例如
甾醇或
胆酸的酶促或合成降解,使用了基本骨架的功能化(“积累”方法)。