Synthesis of chiral hexacyclic steroids via [8π + 2π] cycloaddition of diazafulvenium methides.
Lopes, Susana M. M.; Correia, Cátia F O; Nunes, Sandra C. C.; Pereira, Nelson A. M.; Ferreira, Ana R. F.; Sousa, Emanuel P.; Gomes, Clara S. B.; Salvador, Jorge A. R.; Pais, Alberto A. C. C.; Pinho E Melo, Teresa M V D; Organic & biomolecular chemistry 13 (2015) 9127–9139; doi:10.1039/c5ob01110h

data_7154606
_publ_section_title
;
 Synthesis of chiral hexacyclic steroids via [8\p + 2\p] cycloaddition of
 diazafulvenium methides.
;
_journal_issue                   34
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              9127
_journal_page_last               9139
_journal_paper_doi               10.1039/c5ob01110h
_journal_volume                  13
_journal_year                    2015
_chemical_formula_moiety         'C14 H14 N2 O4 S'
_chemical_formula_sum            'C14 H14 N2 O4 S'
_chemical_formula_weight         306.33
_chemical_name_systematic
'Ethyl 2,2-dioxo-6-phenyl-1H,3H-pyrazolo[1,5-c][1,3]thiazole-7-carboxylate'
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2015-06-03 deposited with the CCDC.
2015-07-20 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 117.059(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.7862(3)
_cell_length_b                   20.9598(7)
_cell_length_c                   8.5716(3)
_cell_measurement_reflns_used    6245
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      30.58
_cell_measurement_theta_min      2.60
_cell_volume                     1405.73(9)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    ORTEP
_computing_publication_material  enCIFer
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    SIR2004
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0308
_diffrn_reflns_av_unetI/netI     0.0302
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       30
_diffrn_reflns_limit_k_min       -31
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            18485
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         31.969
_diffrn_reflns_theta_min         1.943
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.248
_exptl_absorpt_correction_T_max  0.907
_exptl_absorpt_correction_T_min  0.886
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.447
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Block
_exptl_crystal_F_000             640
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.400
_exptl_crystal_size_min          0.400
_refine_diff_density_max         0.350
_refine_diff_density_min         -0.347
_refine_diff_density_rms         0.051
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.046
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     191
_refine_ls_number_reflns         4845
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.046
_refine_ls_R_factor_all          0.0561
_refine_ls_R_factor_gt           0.0408
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0570P)^2^+0.2227P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1048
_refine_ls_wR_factor_ref         0.1105
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3803
_reflns_number_total             4845
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c5ob01110h2.cif
_cod_data_source_block           18a
_cod_depositor_comments
'Adding full bibliography for 7154606--7154607.cif.'
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7154606
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.886
_shelx_estimated_absorpt_t_max   0.907
_shelx_res_checksum              21340