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_4025756
_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 O2'
_chemical_formula_sum            'C19 H28 O2'
_chemical_formula_weight         288.41
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 103.190(7)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.1254(10)
_cell_length_b                   6.3299(7)
_cell_length_c                   23.590(2)
_cell_measurement_reflns_used    1067
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      49.37
_cell_measurement_theta_min      4.10
_cell_volume                     1617.4(3)
_computing_cell_refinement       'Bruker Prospector Apex2'
_computing_data_collection       'Bruker Prospector Apex2'
_computing_data_reduction        'Bruker SAINT APEX2'
_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      100(2)
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  'montel mirrors'
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.2137
_diffrn_reflns_av_sigmaI/netI    0.2152
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            6562
_diffrn_reflns_theta_full        50.64
_diffrn_reflns_theta_max         50.64
_diffrn_reflns_theta_min         3.85
_exptl_absorpt_coefficient_mu    0.577
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.184
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.233
_refine_diff_density_min         -0.249
_refine_diff_density_rms         0.061
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.832
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     100
_refine_ls_number_reflns         1685
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.832
_refine_ls_R_factor_all          0.1508
_refine_ls_R_factor_gt           0.0649
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0474P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1174
_refine_ls_wR_factor_ref         0.1391
_reflns_number_gt                776
_reflns_number_total             1685
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo101242e_si_006.cif
_cod_data_source_block           p21n
_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_cell_volume        1617.5(3)
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               4025756