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_2102075
_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 O3'
_chemical_formula_sum            'C18 H26 O3'
_chemical_formula_weight         290.39
_chemical_melting_point          161.0(10)
_chemical_name_common            2-Oxa-5-alpha-androstane-3,17-dione
_chemical_name_systematic
;
 2-Oxa-5-alpha-androstane-3,17-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'
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.3180(4)
_cell_length_b                   6.4489(5)
_cell_length_c                   38.841(3)
_cell_measurement_reflns_used    91
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      51
_cell_measurement_theta_min      14
_cell_volume                     1582.5(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-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full .968
_diffrn_measured_fraction_theta_max .968
_diffrn_measurement_device_type  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    .0141
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       44
_diffrn_reflns_limit_l_min       -47
_diffrn_reflns_number            1736
_diffrn_reflns_theta_full        70.15
_diffrn_reflns_theta_max         70.15
_diffrn_reflns_theta_min         4.55
_diffrn_standards_decay_%        'less than 2'
_diffrn_standards_interval_count 100
_diffrn_standards_number         2
_exptl_absorpt_coefficient_mu    .644
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.219
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       prism
_exptl_crystal_F_000             632
_exptl_crystal_size_max          .45
_exptl_crystal_size_mid          .40
_exptl_crystal_size_min          .10
_refine_diff_density_max         .161
_refine_diff_density_min         -.111
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -.2(3)
_refine_ls_extinction_coef       .0047(5)
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.045
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     219
_refine_ls_number_reflns         1736
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          .0370
_refine_ls_R_factor_gt           .0307
_refine_ls_shift/su_max          .001
_refine_ls_shift/su_mean         .000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0488P)^2^+0.2430P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .0886
_reflns_number_gt                1567
_reflns_number_total             1736
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ka0049.cif
_cod_data_source_block           11
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '160-162' was changed to '161.0(10)'
- 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 '160-162' was changed to '161.0(10)'
- the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_database_code               2102075