Diosgenone: a second <i>P</i>2~1~ polymorph
Hernández Linares, María-Guadalupe; Guerrero-Luna, Gabriel; Bernès, Sylvain; Flores-Alamo, Marcos; Fernández-Herrera, María A.; Acta Crystallographica Section E 68 (2012) o2358–; doi:10.1107/S160053681202908X

data_2235807
_publ_section_title
;
 Diosgenone: a second <i>P</i>2~1~ polymorph
;
_journal_coeditor_code           GG2086
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o2358
_journal_paper_doi               10.1107/S160053681202908X
_journal_volume                  68
_journal_year                    2012
_chemical_formula_iupac          'C27 H40 O3'
_chemical_formula_moiety         'C27 H40 O3'
_chemical_formula_sum            'C27 H40 O3'
_chemical_formula_weight         412.59
_chemical_melting_point          432
_chemical_name_common            Diosgenone
_chemical_name_systematic
;
(20<i>S</i>,22<i>R</i>,25<i>R</i>)-Spirost-4-en-3-one
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 97.207(5)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.3396(6)
_cell_length_b                   7.6466(4)
_cell_length_c                   29.9511(17)
_cell_measurement_reflns_used    2248
_cell_measurement_temperature    136(2)
_cell_measurement_theta_max      25.9981
_cell_measurement_theta_min      3.4212
_cell_volume                     2349.3(2)
_computing_cell_refinement       'CrysAlis CCD (Oxford Diffraction, 2009)'
_computing_data_collection       'CrysAlis CCD (Oxford Diffraction, 2009)'
_computing_data_reduction        'CrysAlis RED (Oxford Diffraction, 2009)'
_computing_molecular_graphics
'SHELXTL (Sheldrick, 2008) and <i>Mercury</i> (Macrae <i>et al.</i>, 2008)'
_computing_publication_material  'SHELXTL (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      136(2)
_diffrn_detector_area_resol_mean 10.4685
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  'Oxford Diffraction Xcalibur (Atlas, Gemini)'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance (Mo) X-ray Source'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0419
_diffrn_reflns_av_sigmaI/netI    0.0627
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -37
_diffrn_reflns_number            11305
_diffrn_reflns_theta_full        26.73
_diffrn_reflns_theta_max         26.73
_diffrn_reflns_theta_min         3.43
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.074
_exptl_absorpt_correction_T_max  0.996
_exptl_absorpt_correction_T_min  0.984
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
;
[CrysAlis PRO (Oxford Diffraction, 2009); based on expressions derived
by
Clark & Reid (1995)]
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.167
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             904
_exptl_crystal_size_max          0.4358
_exptl_crystal_size_mid          0.1862
_exptl_crystal_size_min          0.0523
_refine_diff_density_max         0.227
_refine_diff_density_min         -0.185
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.033
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_constraints    0
_refine_ls_number_parameters     549
_refine_ls_number_reflns         5346
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0818
_refine_ls_R_factor_gt           0.0519
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0356P)^2^+0.2215P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0877
_refine_ls_wR_factor_ref         0.0985
_reflns_number_gt                3908
_reflns_number_total             5346
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            gg2086.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               2235807
_cod_database_fobs_code          2235807