Two Steroidal Epimers, (5β,17α)-Pregna-20-yno[3,4-<i>c</i>][1,2,5]oxadiazol-17-ol (the 5β-Epimer) and (5α,17α)-Pregna-20-yno[3,4-<i>c</i>][1,2,5]oxadiazol-17-ol (the 5α-Epimer)
Lisgarten, D. R.; Palmer, R. A.; Maes, D.; Lisgarten, J.; Wyns, L.; Acta Crystallographica Section C 51 (1995) 666–670; doi:10.1107/S0108270194007237

data_2003347
_publ_section_title
;
 Two Steroidal Epimers,
 (5\b,17\a)-Pregna-20-yno[3,4-<i>c</i>][1,2,5]oxadiazol-17-ol (the
 5\b-Epimer) and
 (5\a,17\a)-Pregna-20-yno[3,4-<i>c</i>][1,2,5]oxadiazol-17-ol (the
 5\a-Epimer)
;
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              666
_journal_page_last               670
_journal_paper_doi               10.1107/S0108270194007237
_journal_volume                  51
_journal_year                    1995
_chemical_compound_source        'acetone recrystallization'
_chemical_formula_moiety         'C21 H28 N2 O2'
_chemical_formula_sum            'C21 H28 N2 O2'
_chemical_formula_weight         340.46
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  'P 32'
_symmetry_space_group_name_H-M   'P 32'
_atom_type_scat_source           'IntTabIV and SHELX76 (Sheldrick, 1976)'
_cell_angle_alpha                90.
_cell_angle_beta                 90.
_cell_angle_gamma                120.
_cell_formula_units_Z            3
_cell_length_a                   15.034(2)
_cell_length_b                   15.034(2)
_cell_length_c                   7.187(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    296
_cell_measurement_theta_max      25
_cell_measurement_theta_min      0
_cell_volume                     1406.8(5)
_diffrn_measurement_device       'Enraf-Nonius CAD-4'
_diffrn_measurement_method       \w-\q
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.5418
_diffrn_reflns_av_R_equivalents  0.021
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       6
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            7378
_diffrn_reflns_theta_max         70
_diffrn_standards_decay_%        <5
_diffrn_standards_interval_count 100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.58
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            'clear, colourless'
_exptl_crystal_density_diffrn    1.206
_exptl_crystal_description       needle/prisms
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.31
_refine_diff_density_min         -0.05
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_obs   ? # 'not calculated'
_refine_ls_number_parameters     250
_refine_ls_number_reflns         3503
_refine_ls_R_factor_obs          0.048
_refine_ls_R_factor_all          0.048
_refine_ls_shift/esd_max         0.682
_refine_ls_structure_factor_coef F
_refine_ls_weighting_details     'w = 1.00/[\s^2^(F) + 0.016534F^2^]'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.052
_refine_ls_wR_factor_all         0.054
_reflns_number_observed          3454
_reflns_number_total             3503
_reflns_observed_criterion       I>3\s(I)
_cod_data_source_file            hr1007.cif
_cod_data_source_block           hr1007a

_refine_ls_R_factor_all, _refine_ls_R_factor_obs, _refine_ls_wR_factor_all
and _refine_ls_wR_factor_obs.
;

5 'Saulius Gra\<zulis' 2023-02-23T20:55:26+02:00
;Changing value of the '_refine_ls_goodness_of_fit_obs' from
'not calculated' to the question mark.
;

_cod_database_code               2003347