Received 4 February 2008
aEscuela de Ingeniería Química, Universidad del Istmo, Ciudad Universitaria S/N, 70760 Sto. Domingo Tehuantepec, Oax., Mexico,bFacultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, San Manuel, 72000 Puebla, Pue., Mexico, and cDEP Facultad de Ciencias Químicas, UANL, Guerrero y Progreso S/N, Col. Treviño, 64570 Monterrey, NL, Mexico
Correspondence e-mail: email@example.com
The title steroid, C29H46O4, is a furostene derivative with a C=C double-bond length of 1.353 (3) Å and an E configuration. The side chain is oriented toward the face of the A-E steroidal nucleus and presents a disordered terminal CH2-OH group [occupancies for resolved sites are 0.591 (9) and 0.409 (9)]. The methyl group at C20 attached to ring E is also oriented toward the face, avoiding steric hindrance with the carbonyl O atom of the acetyl group. The furostene and acetyl functionalities form an ,-unsaturated ketone system, with an s-cis configuration. All hydroxy and carbonyl groups are involved in weak intermolecular hydrogen bonds. The absolute configuration was assigned from the synthesis.
The diacetate of the title compound has been characterized by X-ray crystallography (Sandoval-Ramírez et al., 2003), as well as a related furost-22-ene derivate with the C20 site substituted by a methyl group and an acetyl group (Meza-Reyes et al., 2004).
Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL-Plus (Release 5.10; Sheldrick, 2008); program(s) used to refine structure: SHELXTL-Plus; molecular graphics: SHELXTL-Plus; software used to prepare material for publication: SHELXTL-Plus.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2197 ).
This work was supported by CONACyT (grant 60397).
Meza-Reyes, S., Montiel-Smith, S., Sandoval-Ramírez, J., Bernès, S., Hernández-Linares, G., Santillan, R. L. & Rincón, S. (2004). Acta Cryst. E60, o1137-o1139.
Sandoval-Ramírez, J., Meza-Reyes, S., Montiel-Smith, S., Bernès, S., Hernández-Linares, G. & Bravo, O. V. (2003). Acta Cryst. E59, o1817-o1819.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
Siemens (1996). XSCANS. Version 2.21. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.