We set out to describe a new and versatile method for preparing 3-aza-11-oxa-1,3,5(10)-trieno steroids via an intramolecular Diels-Alder cycloaddition of o-quinodimethanes as the key step. The characteristic H-1 and C-13 NMR spectroscopic features of the synthesized compounds are reported. (c) 2006 Elsevier Inc. All rights reserved.
First total syntheses of (±)-3-aza-11-selena and (±)-3-aza-11-tellura steroids
An efficient synthesis of 11-selena and 11-tellura steroids bearing a pyridine as an A ring was achieved via an intramolecular Diels–Alder cycloaddition of o-quinodimethanes, which were generated from a 3-azabicyclo[4.2.0]octa-1,3,5-trien-7-one ketal. The major isomer matches the trans-anti-trans ring configuration of natural products. Finally, the vinyl groups of the synthesized 11-hetero steroids
通过由3-氮杂双环[4.2.0] octa-1生成的邻喹啉甲烷的分子内Diels-Alder环加成反应,可以有效合成带有硒原子作为A环的11-硒环和11-甾醇类固醇。 3,5-trien-7-缩酮。主要异构体相匹配的反-反-反式天然产物的环形结构。最终,合成的11-杂类固醇的乙烯基已通过瓦克方法以良好的收率被氧化。报告了合成化合物的特征1 H和13 C NMR光谱特征。
First Total Synthesis of<i>N</i>-Oxido-3-aza-1,3,5(10)-trieno Steroids
An efficient synthesis of 3-aza-steroids bearing a pyridine as an A ring was achieved via intramolecular cycloaddition of orthoquinodimethanes, which were generated from a 3-azabicyclo[4.2.0]octa-l,3,5-trien-7-one ketal.