A new efficient synthesis of 11-aza steroids
✍ Scribed by Frédéric Cachoux; Malika Ibrahim-Ouali; Maurice Santelli
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- French
- Weight
- 99 KB
- Volume
- 42
- Category
- Article
- ISSN
- 0040-4039
No coin nor oath required. For personal study only.
✦ Synopsis
The total synthesis and stereochemistry of new 11-aza steroids are reported. Our strategy involves an intramolecular Diels-Alder cycloaddition of o-quinodimethanes which are generated by thermal ring opening of a benzocyclobutene.
📜 SIMILAR VOLUMES
We wish to report various novel reactions and intermediates which permit the development of efficient total syntheses of a wide variety of 11-oxygenated steroids from intermediates which have previously been converted to estrone, 1,2 equilenin, 1,2 equilin,3 and other steroid hormones.
Conjugate 1,4-addition of 1- [(tert-butyldimethylsilyl)oxy]-2-methyl-1,3-cyclohexadiene (5) to 2-methylcyclopentenone in highly polar media and subsequent alkylation of the resultant silyl enol ether (4) with phenylthiodienyl carbonate I0 in 5.0 M LiC104.Et20 provides substrate 2. Exposure of 2 to T