16α,17-Epoxypregn-4-ene-3,11,20-trione
Nie, Qiang; Wang, Jingkang; Wang, Shi; Zhang, Meijing; Acta Crystallographica Section E 61 (2005) o398–o399; doi:10.1107/S1600536805001443

data_2205059
_publ_section_title
;
 16\a,17-Epoxypregn-4-ene-3,11,20-trione
;
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o398
_journal_page_last               o399
_journal_paper_doi               10.1107/S1600536805001443
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C21 H26 O4'
_chemical_formula_moiety         'C21 H26 O4'
_chemical_formula_sum            'C21 H26 O4'
_chemical_formula_weight         342.42
_chemical_melting_point          465.5
_chemical_name_common
;
16\a,17-Epoxypregn-4-ene-3,11,20-trione
;
_chemical_name_systematic
;17-acetyl-10,13-dimethyl-1,2,6,7,9,10,12,13,14,15,16,
17-dodecahydro-8H-20-oxa-cyclopropa[16,17]cyclopenta[a]phenanthrene-3,11-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                   7.5364(12)
_cell_length_b                   9.9000(16)
_cell_length_c                   23.288(4)
_cell_measurement_reflns_used    2892
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      23.89
_cell_measurement_theta_min      2.24
_cell_volume                     1737.5(5)
_computing_cell_refinement       'SAINT (Bruker, 1998)'
_computing_data_collection       'SMART (Bruker, 1998)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL (Bruker, 1998)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker SMART CCD area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0418
_diffrn_reflns_av_sigmaI/netI    0.0318
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            11707
_diffrn_reflns_theta_full        27.96
_diffrn_reflns_theta_max         27.96
_diffrn_reflns_theta_min         1.75
_exptl_absorpt_coefficient_mu    0.089
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.309
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             736
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.24
_refine_diff_density_max         0.222
_refine_diff_density_min         -0.155
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.073
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     229
_refine_ls_number_reflns         2396
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.073
_refine_ls_R_factor_all          0.0524
_refine_ls_R_factor_gt           0.0396
_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^)+(0.0616P)^2^+0.0814P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1023
_refine_ls_wR_factor_ref         0.1086
_reflns_number_gt                1925
_reflns_number_total             2396
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            fl6141.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        1737.6(5)
_cod_original_sg_symbol_H-M      'P21 21 21'
_cod_database_code               2205059
_cod_database_fobs_code          2205059