Synthesis of 6,19-cyclopregnanes. Constrained analogues of steroid hormones.
Di Chenna, Pablo H.; Veleiro, Adriana S.; Sonego, Juan M.; Ceballos, Nora R.; Garland, M. Teresa; Baggio, Ricardo F.; Burton, Gerardo; Organic & biomolecular chemistry 5 (2007) 2453–2457; doi:10.1039/b706828j

data_7151136
_publ_section_title
;
 Synthesis of 6,19-cyclopregnanes. Constrained analogues of steroid
 hormones.
;
_journal_issue                   15
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              2453
_journal_page_last               2457
_journal_paper_doi               10.1039/b706828j
_journal_volume                  5
_journal_year                    2007
_chemical_formula_moiety         'C21 H28 O2'
_chemical_formula_sum            'C21 H28 O2'
_chemical_formula_weight         312.43
_chemical_name_common            6,19-cyclopregn-4-ene-3,20-dione
_chemical_name_systematic
;
6,19-cyclopregn-4-ene-3,20-dione
;
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2007-05-08 # Formatted by publCIF
;
_cell_angle_alpha                90.00
_cell_angle_beta                 111.863(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.3312(12)
_cell_length_b                   11.4371(12)
_cell_length_c                   14.5628(16)
_cell_measurement_temperature    298(2)
_cell_volume                     1751.5(3)
_computing_cell_refinement       'SAINT-NT (Bruker, 2001 )'
_computing_data_collection       'SMART-NT (Bruker, 2001)'
_computing_data_reduction        'SAINT-NT (Bruker, 2001 )'
_computing_molecular_graphics    'SHELXTL-NT (Bruker, 2001)'
_computing_publication_material
'SHELXTL-NT (Bruker, 2001), PLATON (Spek, 2005)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.928
_diffrn_measurement_device_type  'Bruker CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0554
_diffrn_reflns_av_sigmaI/netI    0.0599
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            13024
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         28.14
_diffrn_reflns_theta_min         1.94
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.074
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.185
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       blocks
_exptl_crystal_F_000             680
_exptl_crystal_size_max          0.26
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.16
_refine_diff_density_max         0.128
_refine_diff_density_min         -0.111
_refine_diff_density_rms         0.027
_refine_ls_abs_structure_details 'Friedel pairs merged '
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.091
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     419
_refine_ls_number_reflns         4172
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.091
_refine_ls_R_factor_all          0.0852
_refine_ls_R_factor_gt           0.0570
_refine_ls_shift/su_max          0.007
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0230P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0832
_refine_ls_wR_factor_ref         0.0901
_reflns_number_gt                2950
_reflns_number_total             4172
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            b706828j.txt
_cod_data_source_block           ExTwin
_cod_original_sg_symbol_Hall     ' P 2yb '
_cod_original_sg_symbol_H-M      ' P 21 '
_cod_database_code               7151136