16α,17-Epoxy-4-pregnene-3,20-dione
Shi Wang; Yongli Wang; Qiang Nie; Lina Zhou; Jiehua Wu; Acta Crystallographica Section E 60 (2004) o2337–o2338; doi:10.1107/S1600536804029095

data_2204658
_publ_section_title
;
 16\a,17-Epoxy-4-pregnene-3,20-dione
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o2337
_journal_page_last               o2338
_journal_paper_doi               10.1107/S1600536804029095
_journal_volume                  60
_journal_year                    2004
_chemical_formula_iupac          'C21 H28 O3'
_chemical_formula_moiety         'C21 H28 O3'
_chemical_formula_sum            'C21 H28 O3'
_chemical_formula_weight         328.43
_chemical_name_systematic
;
16\a,17-epoxy-4-pregnene-3,20-dione
;
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.33570(10)
_cell_length_b                   12.1537(2)
_cell_length_c                   20.32040(10)
_cell_measurement_reflns_used    16882
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.48
_cell_measurement_theta_min      1.95
_cell_volume                     1811.68(4)
_computing_cell_refinement       RAPID-AUTO
_computing_data_collection       'RAPID-AUTO (Rigaku, 2001)'
_computing_data_reduction        RAPID-AUTO
_computing_molecular_graphics    'ORTEPII (Johnson, 1976)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Rigaku R-AXIS RAPID IP'
_diffrn_measurement_method       oscillation
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'retating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.07017
_diffrn_reflns_av_sigmaI/netI    0.0567
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            16882
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         1.95
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.079
_exptl_absorpt_correction_T_max  0.9760
_exptl_absorpt_correction_T_min  0.9446
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(ABSCOR; Higashi, 1995)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.204
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             712
_exptl_crystal_size_max          0.73
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.31
_refine_diff_density_max         0.137
_refine_diff_density_min         -0.190
_refine_ls_extinction_coef       0.028(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   0.834
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     218
_refine_ls_number_reflns         2380
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.834
_refine_ls_R_factor_all          0.0774
_refine_ls_R_factor_gt           0.0381
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0442P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0812
_refine_ls_wR_factor_ref         0.0924
_reflns_number_gt                1311
_reflns_number_total             2380
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            cv6409.cif
_cod_data_source_block           I
_cod_database_code               2204658
_cod_database_fobs_code          2204658