| Autor: |
Ramírez Hernández J; Benemérita Universidad Autónoma de Puebla, Facultad de Ciencias Químicas, Ciudad Universitaria, Puebla, Pue. 72570, Mexico., Sandoval-Ramírez J, Meza-Reyes S, Vega Báez JL, Bernès S |
| Jazyk: |
angličtina |
| Zdroj: |
Acta crystallographica. Section E, Structure reports online [Acta Crystallogr Sect E Struct Rep Online] 2012 Dec 01; Vol. 68 (Pt 12), pp. o3331. Date of Electronic Publication: 2012 Nov 10. |
| DOI: |
10.1107/S1600536812045278 |
| Abstrakt: |
THE STRUCTURE OF THE TITLE STEROID [ALTERNATIVE NAME: 3β,6β-diacet-oxy-5β-methyl-19-norcholest-9(10)-ene], C31H50O4, confirms the generally accepted mechanism for the rearrangement of a cholestan-5α-ol derivative reported a century ago by Westphalen. The methyl group at position 10 of the starting material migrates to position 5 in the steroidal nucleus, while a Δ(9) bond is formed, as indicated by the C=C bond length of 1.347 (4) Å. The methyl transposition leaves the 5R configuration unchanged, with the methyl oriented towards the β face. During the rearrangement, the steroidal B ring experiences a conformational distortion from chair to envelope with the C atom at position 6 as the flap. In the title structure, the isopropyl group of the side chain is disordered over two positions, with occupancies of 0.733 (10) and 0.267 (10). The carbonyl O atom in the acetyl group at C3 is also disordered with an occupancy ratio of 0.62 (4):0.38 (4). |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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