Enantioselective total synthesis of (+)- and (-)-nigellamine A2.
Bian, Jianwei; Van Wingerden, Matthew; Ready, Joseph M; Journal of the American Chemical Society 128 (2006) 7428–7429; doi:10.1021/ja061559n

data_4101504
_publ_section_title
;
 Enantioselective total synthesis of (+)- and (-)-nigellamine A2.
;
_journal_issue                   23
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              7428
_journal_page_last               7429
_journal_paper_doi               10.1021/ja061559n
_journal_volume                  128
_journal_year                    2006
_chemical_formula_sum            'C23 I O3 Si'
_chemical_formula_weight         479
_chemical_name_systematic
; 
 ? 
;
_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                 96.16
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   12.6650(3)
_cell_length_b                   20.5240(5)
_cell_length_c                   19.9440(5)
_cell_measurement_temperature    293(2)
_cell_volume                     5154.2(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.985
_diffrn_measured_fraction_theta_max 0.985
_diffrn_measurement_device_type  'Kappa CCD'
_diffrn_measurement_method       Collect
_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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.1942
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            4005
_diffrn_reflns_theta_full        18.85
_diffrn_reflns_theta_max         18.85
_diffrn_reflns_theta_min         2.01
_exptl_absorpt_coefficient_mu    2.6
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.298
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    .
_exptl_crystal_description       needles
_exptl_crystal_F_000             2072
_exptl_crystal_size_max          0.6
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.399
_refine_diff_density_min         -0.570
_refine_diff_density_rms         0.103
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.937
_refine_ls_hydrogen_treatment    none
_refine_ls_matrix_type           full
_refine_ls_number_parameters     505
_refine_ls_number_reflns         4005
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.937
_refine_ls_R_factor_all          0.1879
_refine_ls_R_factor_gt           0.0834
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.1132P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1834
_refine_ls_wR_factor_ref         0.2367
_reflns_number_gt                1806
_reflns_number_total             4005
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja061559nsi20060517_051321.cif
_cod_data_source_block           shelxl
_cod_original_sg_symbol_H-M      P21/n
_cod_original_formula_sum        'C23  I1 O3 Si1'
_cod_database_code               4101504