## Abstract The photochemical cyclisation of 11‐keto steroids to 11β, 19‐cyclo‐11‐hydroxy compounds is strongly influenced by steric factors. The presence of a __gem__‐dimethyl group at C‐4 gives rise to a marked improvement in the yield of the cyclic product. The nature of this steric interaction
Photochemische Reaktionen. 12. Mitteilung. Zur UV.-Bestrahlung von 17-Oxo-Steroiden
✍ Scribed by H. Wehrli; K. Schaffner
- Publisher
- John Wiley and Sons
- Year
- 1962
- Tongue
- German
- Weight
- 345 KB
- Volume
- 45
- Category
- Article
- ISSN
- 0018-019X
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✦ Synopsis
The behaviour of inorganic cations in thin layer chromatography experiments has been studied. The determining factors were found to be ion-exchange properties of the absorbent and coordination tendencies of the solvent.
📜 SIMILAR VOLUMES
## Abstract 1. The photochemical reactivity of testosterone (**1**) is strongly influenced by the nature of the solvent. Dimerization (→**18**), pinacone formation (→**19**)), reactions between the steroid and the solvent molecules (→**20a**, **20b**, **21**) and stereospecific isomerizations (→**2
## Abstract The UV.‐isomerisation of 11‐oxo‐14β,17α‐pregnane **9** to the 11,19‐cyclo‐derivative **11** is described. In addition the Pb(OAc)~4~‐fragmentation of photoproduct **11** was investigated. **11** yielded besides the expected 11‐oxo‐19‐hydroxy‐pregnane **18** the novel 9,11‐seco‐11,19‐cyc