19-Nor-Δ4-3-oxosteroid (IX) was synthesized starting from 3α, 5α-cyclo-6β, 19-oxidosteroid (I) through 3β-substituted-Δ5-steroid-19-oic acid (VII), whose synthesis was achieved by the three methods : i) Hydrolysis of 3β-hydroxy-Δ5-steroid-19-oic acid 3, 19-lactone (VI) which was prepared by oxidizing either 3β, 19-dihydroxy-Δ5-steroid (III) or 3β-hydroxy-19-oxo-Δ5-steroid (V) with Jones reagent or Oppenauer reaction, ii) Oxidation of 3β, 19-dihydroxy-Δ5-steroid 3-acetate (III) with the excess Jones reagent, iii) Reduction of 3α, 5α-cyclo-6-oxo-19-oic acid (IV) with sodium borohydride and subsequent acid-catalysed solvolysis of a mixture of resultant 6-epimeric hydroxy acids (XIII and XIV) in a suitable solvent. 3β-Substituted-Δ5-steroid-19-oic acid (VII) was in turn converted to 19-nor-Δ4-3-oxosteroid (IX) in two ways : i) Oxidation of 3β-hydroxy compound and subsequent acid-treatment of the resultant Δ5-3- oxosteroid-19-oic acid (VIII), ii) Pyrolysis of the 3β-acetoxy-Δ5-steroid-19-oic acid (VII) to afford 3β-acetoxy-Δ5 (10)-steroid (XI), followed by alkaline hydrolysis, Jones oxidation, and acid-treatment, successively.
19-Nor-Δ4-3-oxosteroid (IX) 由 3α,5α-cyclo-6β,19-oxidosteroid (I) 通过 3β 取代-Δ5-甾-19-酸 (VII) 合成,其合成是通过以下三种方法实现的:i) 3β-羟基-Δ5-类
固醇-19-酸 3,19-内
酯(VI)的
水解,该内
酯是通过琼斯试剂或奥本纳反应
氧化 3β,19-二羟基-Δ5-类
固醇(III)或 3β-羟基-19-
氧代-Δ5-类
固醇(V)制备的; ii)
氧化 3β,19-二羟基-Δ5-类
固醇(III)或 3β-羟基-19-
氧代-Δ5-类
固醇(V)、19-二羟基-Δ5-类
固醇 3-
乙酸酯 (III) 与过量的琼斯试剂发生
氧化反应,iii) 用
硼氢化钠还原 3α,5α-环-6-
氧代-19-酸 (IV),然后在适当的溶剂中对生成的 6-二元羟基酸 (XIII 和 XIV) 混合物进行酸催化溶解。3β 取代-Δ5-类
固醇-19-酸(VII)又通过两种方法转化为 19-去甲-Δ4-3-类
固醇(IX):i) 3β-羟基化合物的
氧化,然后对得到的Δ5-3-类
固醇-19-酸(VIII)进行酸处理,ii) 3β-乙酰
氧基-Δ5-类
固醇-19-酸(VII)的热解,得到 3β-乙酰
氧基-Δ5(10)-类
固醇(XI),然后依次进行碱性
水解、琼斯
氧化和酸处理。