First total synthesis of antiostatin A1, a potent carbazole-based naturally occurring antioxidant.
Alayrac, Carole; Schollmeyer, Dieter; Witulski, Bernhard; Chemical communications (Cambridge, England) 34 (2009) 1464–1466; doi:10.1039/b820291e

data_7104262
_publ_section_title
;
 First total synthesis of antiostatin A1, a potent carbazole-based
 naturally occurring antioxidant.
;
_journal_issue                   12
_journal_name_full
'Chemical communications (Cambridge, England)'
_journal_page_first              1464
_journal_page_last               1466
_journal_paper_doi               10.1039/b820291e
_journal_volume                  34
_journal_year                    2009
_chemical_compound_source        synthetic
_chemical_formula_moiety         'C20 H24 N2 O2'
_chemical_formula_sum            'C20 H24 N2 O2'
_chemical_formula_weight         324.41
_chemical_melting_point          490
_chemical_name_common            'Antiostatin A1'
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_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                 90.069(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   4.9084(2)
_cell_length_b                   24.3209(12)
_cell_length_c                   14.3390(8)
_cell_measurement_reflns_used    2220
_cell_measurement_temperature    193(2)
_cell_measurement_theta_max      23.6
_cell_measurement_theta_min      2.1
_cell_volume                     1711.74(15)
_computing_cell_refinement       'APEX2 V2.0 (Bruker, 2006)'
_computing_data_collection       'APEX2 V2.0 (Bruker, 2006)'
_computing_data_reduction        'APEX2 V2.0 (Bruker, 2006)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR-97 (Altomare, 1997)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device       '\k-geometry diffractometer'
_diffrn_measurement_device_type  'SMART CCD'
_diffrn_measurement_method       'CCD scan'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.1027
_diffrn_reflns_av_sigmaI/netI    0.1144
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       31
_diffrn_reflns_limit_k_min       -31
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            18097
_diffrn_reflns_theta_full        27.90
_diffrn_reflns_theta_max         27.90
_diffrn_reflns_theta_min         1.42
_diffrn_source                   'sealed Tube'
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.259
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             696
_exptl_crystal_recrystallization_method 'ethyl acetate and pentane'
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.257
_refine_diff_density_min         -0.248
_refine_diff_density_rms         0.048
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.860
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     220
_refine_ls_number_reflns         4085
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.865
_refine_ls_R_factor_all          0.1064
_refine_ls_R_factor_gt           0.0477
_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^)+(0.0500P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_obs         0.0979
_refine_ls_wR_factor_ref         0.1120
_reflns_number_gt                2250
_reflns_number_total             4085
_reflns_threshold_expression     >2sigma(I)
_cod_duplicate_entry             7104244
_cod_data_source_file            b820291e.txt
_cod_data_source_block           ca403
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               7104262