Studies toward the Total Syntheses of Cucurbitacins B and D
Michael E. Jung; Rebecca M. Lui; Journal of Organic Chemistry 75 (2010) 7146–7158; doi:10.1021/jo101242e

data_4025752
_publ_section_title
;
 Studies toward the Total Syntheses of Cucurbitacins B and D
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              7146
_journal_page_last               7158
_journal_paper_doi               10.1021/jo101242e
_journal_volume                  75
_journal_year                    2010
_chemical_formula_moiety         'C19 H28 O3'
_chemical_formula_sum            'C19 H28 O3'
_chemical_formula_weight         304.41
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 100.907(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.124(2)
_cell_length_b                   13.287(2)
_cell_length_c                   9.6740(16)
_cell_measurement_reflns_used    3811
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      27.47
_cell_measurement_theta_min      4.22
_cell_volume                     1656.5(4)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.993
_diffrn_measurement_device_type  '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  0.0264
_diffrn_reflns_av_sigmaI/netI    0.0259
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            14964
_diffrn_reflns_theta_full        28.73
_diffrn_reflns_theta_max         28.73
_diffrn_reflns_theta_min         3.79
_exptl_absorpt_coefficient_mu    0.081
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.221
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             664
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.4
_exptl_crystal_size_min          0.3
_refine_diff_density_max         0.243
_refine_diff_density_min         -0.182
_refine_diff_density_rms         0.037
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.057
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     221
_refine_ls_number_reflns         4245
_refine_ls_number_restraints     42
_refine_ls_restrained_S_all      1.054
_refine_ls_R_factor_all          0.0670
_refine_ls_R_factor_gt           0.0480
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0681P)^2^+0.2299P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1272
_refine_ls_wR_factor_ref         0.1399
_reflns_number_gt                3092
_reflns_number_total             4245
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo101242e_si_001.cif
_cod_data_source_block           mj607sa
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to the built-in table from CIF Core dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 
;
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4025752