Sequential one-pot cyclizations: concise access to the ABCE tetracyclic framework of strychnos alkaloids.
Sirasani, Gopal; Andrade, Rodrigo B.; Organic letters 11 (2009) 2085–2088; doi:10.1021/ol9004799

data_1503875
_publ_section_title
;
 Sequential one-pot cyclizations: concise access to the ABCE tetracyclic
 framework of strychnos alkaloids.
;
_journal_issue                   10
_journal_name_full               'Organic letters'
_journal_page_first              2085
_journal_page_last               2088
_journal_paper_doi               10.1021/ol9004799
_journal_volume                  11
_journal_year                    2009
_chemical_formula_sum            'C23 H22 N2 O3'
_chemical_formula_weight         374.43
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_Int_Tables_number      14
_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
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 93.688(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.0163(7)
_cell_length_b                   9.4598(8)
_cell_length_c                   25.816(2)
_cell_measurement_temperature    143(1)
_cell_volume                     1953.6(3)
_computing_data_collection       'CrystalClear (Rigaku, 1999)'
_computing_data_reduction        'CrystalClear (Rigaku, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR97 (Altomare, 1999)'
_diffrn_ambient_temperature      143(1)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device       'CCD Area Detector'
_diffrn_measurement_device_type  'Rigaku Mercury'
_diffrn_measurement_method       'phi and omega rotations'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0214
_diffrn_reflns_av_sigmaI/netI    0.0166
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            15485
_diffrn_reflns_theta_full        25.04
_diffrn_reflns_theta_max         25.04
_diffrn_reflns_theta_min         2.55
_exptl_absorpt_coefficient_mu    0.085
_exptl_absorpt_correction_T_max  1.0000
_exptl_absorpt_correction_T_min  0.8566
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_density_diffrn    1.273
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             792
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.22
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.162
_refine_diff_density_min         -0.180
_refine_diff_density_rms         0.038
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.004
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     342
_refine_ls_number_reflns         3458
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.004
_refine_ls_R_factor_all          0.0468
_refine_ls_R_factor_gt           0.0410
_refine_ls_shift/su_max          0.010
_refine_ls_shift/su_mean         0.002
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0602P)^2^+0.6233P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1018
_refine_ls_wR_factor_ref         0.1075
_reflns_number_gt                3049
_reflns_number_total             3458
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol9004799_si_002.cif
_cod_data_source_block           shelxl
_cod_depositor_comments
;
The following automatic conversions were performed:
'_atom_site_symetry_multiplicity' tag replaced with
'_atom_site_symmetry_multiplicity'.

Automatic conversion script
Id: cif_correct_tags 1440 2010-10-19 06:21:57Z saulius 
;
_cod_original_cell_volume        1953.7(3)
_cod_original_sg_symbol_H-M      'P 21/c     '
_cod_database_code               1503875