20-Carboxamidopregnene derivatives, such as 3β-acetoxy-5α-pregn-20-ene-20-carboxamides and 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 ranging from simple primary amines to α-amino acid esters. The novelty of this methodology lies in the application of facile, moderate or high-yielding reactions to obtain otherwise hardly accessible steroidal 20-carboxamides of pharmaceutical importance. In other words, instead of the enzymatic or synthetic degradation of e.g., sterols or cholanic acids, functionalization of the basic skeleton (a ‘building-up’ approach) was used.

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）。