Crystal chemistry of some synthetic 2-oxa-steroids: conformation, packing motifs and isostructurality
Anthony, Addlagatta; Jaskólski, Mariusz; Nangia, Ashwini; Acta Crystallographica Section B 56 (2000) 512–525; doi:10.1107/S0108768199015542

data_2102079
_publ_section_title
;
 Crystal chemistry of some synthetic 2-oxa-steroids: conformation,
 packing motifs and isostructurality
;
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section B'
_journal_page_first              512
_journal_page_last               525
_journal_paper_doi               10.1107/S0108768199015542
_journal_volume                  56
_journal_year                    2000
_chemical_formula_moiety         'C18 H26 O4'
_chemical_formula_sum            'C18 H26 O4'
_chemical_formula_weight         306.39
_chemical_melting_point          228.5(15)
_chemical_name_common            6,17-dihydroxy-2-oxaandrost-4-ene-3-one
_chemical_name_systematic
;
6,17-dihydroxy-2-oxaandrost-4-ene-3-one
;
_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'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.3361(7)
_cell_length_b                   9.6261(7)
_cell_length_c                   17.764(2)
_cell_measurement_reflns_used    56
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      72
_cell_measurement_theta_min      13
_cell_volume                     1596.5(2)
_computing_cell_refinement       'Kuma KM-4'
_computing_data_collection       'Kuma KM-4'
_computing_data_reduction        'Kuma KM-4'
_computing_molecular_graphics    'ORTEP and PLUTO'
_computing_publication_material  SHELXL-93
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       KM-4
_diffrn_measurement_method       \w--2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  .0000
_diffrn_reflns_av_sigmaI/netI    .0113
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            1746
_diffrn_reflns_theta_max         70.13
_diffrn_reflns_theta_min         4.98
_diffrn_standards_decay_%        'less than 1'
_diffrn_standards_interval_count 100
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    .714
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.275
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             664
_exptl_crystal_size_max          .5
_exptl_crystal_size_mid          .4
_exptl_crystal_size_min          .2
_refine_diff_density_max         .174
_refine_diff_density_min         -.106
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   .1(3)
_refine_ls_extinction_coef       .0007(2)
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_all   1.058
_refine_ls_goodness_of_fit_obs   1.059
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     234
_refine_ls_number_reflns         1741
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.218
_refine_ls_restrained_S_obs      1.059
_refine_ls_R_factor_all          .0351
_refine_ls_R_factor_obs          .0305
_refine_ls_shift/esd_max         .042
_refine_ls_shift/esd_mean        .006
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0538P)^2^+0.2314P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         .1024
_refine_ls_wR_factor_obs         .0859
_reflns_number_observed          1634
_reflns_number_total             1746
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ka0049.cif
_cod_data_source_block           15
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '227-230' was changed to '228.5(15)'
- the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_chemical_melting_point' value '227-230' was changed to '228.5(15)'
- the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0538P)^2^+0.2314P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0538P)^2^+0.2314P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_database_code               2102079