Enantioselective synthesis of iridal, the parent molecule of the iridal triterpenoid class.
Corbu, Andrei; Aquino, Maurizio; Pratap, T. V.; Retailleau, Pascal; Arseniyadis, Siméon; Organic letters 10 (2008) 1787–1790; doi:10.1021/ol8005425

data_1504668
_publ_section_title
;
 Enantioselective synthesis of iridal, the parent molecule of the iridal
 triterpenoid class.
;
_journal_issue                   9
_journal_name_full               'Organic letters'
_journal_page_first              1787
_journal_page_last               1790
_journal_paper_doi               10.1021/ol8005425
_journal_volume                  10
_journal_year                    2008
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C30 H39 N O8'
_chemical_formula_sum            'C30 H39 N O8'
_chemical_formula_weight         541.62
_chemical_name_common            'p-nitrobenzoyl ester'
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.302(2)
_cell_length_b                   11.179(3)
_cell_length_c                   35.809(6)
_cell_measurement_reflns_used    15118
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      19.98
_cell_measurement_theta_min      0.41
_cell_volume                     2923.1(12)
_computing_cell_refinement
'DENZO (Otwinowski & Minor, 1997) COLLECT (Nonius B.V., 1999)'
_computing_data_collection
'DENZO (Otwinowski & Minor, 1997) COLLECT (Nonius B.V., 1999)'
_computing_data_reduction        'SCALEPACK (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'PLATON (Spek, 2003)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.938
_diffrn_measured_fraction_theta_max 0.938
_diffrn_measurement_device_type  'Nonius kappa-CCD diffractometer'
_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     0.71069
_diffrn_reflns_av_R_equivalents  0.0296
_diffrn_reflns_av_sigmaI/netI    0.0435
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       37
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            7781
_diffrn_reflns_theta_full        21.73
_diffrn_reflns_theta_max         21.73
_diffrn_reflns_theta_min         2.27
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.089
_exptl_absorpt_correction_T_max  0.98
_exptl_absorpt_correction_T_min  0.88
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Scalepack (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.231
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       stick
_exptl_crystal_F_000             1160
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.218
_refine_diff_density_min         -0.159
_refine_diff_density_rms         0.027
_refine_ls_extinction_coef       0.020(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.027
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     357
_refine_ls_number_reflns         1912
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.027
_refine_ls_R_factor_all          0.0599
_refine_ls_R_factor_gt           0.0406
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0548P)^2^+0.5929P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0944
_refine_ls_wR_factor_ref         0.1057
_reflns_number_gt                1503
_reflns_number_total             1915
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol8005425-file002.cif
_cod_data_source_block           satv624
_cod_original_sg_symbol_H-M      P212121
_cod_database_code               1504668