Generation of N-acyliminium ions via intramolecular conjugate addition reactions: a strategy for the total synthesis of nakadomarin A.
Nilson, Mark G.; Funk, Raymond L.; Organic letters 8 (2006) 3833–3836; doi:10.1021/ol061463y

data_1506151
_publ_section_title
;
 Generation of N-acyliminium ions via intramolecular conjugate addition
 reactions: a strategy for the total synthesis of nakadomarin A.
;
_journal_issue                   17
_journal_name_full               'Organic letters'
_journal_page_first              3833
_journal_page_last               3836
_journal_paper_doi               10.1021/ol061463y
_journal_volume                  8
_journal_year                    2006
_chemical_formula_moiety         'C20 H26 N2 O6'
_chemical_formula_sum            'C20 H26 N2 O6'
_chemical_formula_weight         390.43
_space_group_IT_number           9
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'C -2yc'
_symmetry_space_group_name_H-M   'C 1 c 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                 110.308(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   18.465(6)
_cell_length_b                   9.250(3)
_cell_length_c                   12.676(4)
_cell_measurement_reflns_used    2502
_cell_measurement_temperature    123(2)
_cell_measurement_theta_max      27.649
_cell_measurement_theta_min      2.351
_cell_volume                     2030.5(11)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_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      123(2)
_diffrn_measured_fraction_theta_full 0.979
_diffrn_measured_fraction_theta_max 0.979
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
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_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            6635
_diffrn_reflns_theta_full        28.40
_diffrn_reflns_theta_max         28.40
_diffrn_reflns_theta_min         2.35
_exptl_absorpt_coefficient_mu    0.095
_exptl_absorpt_correction_T_max  0.979
_exptl_absorpt_correction_T_min  0.972
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.277
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             832
_exptl_crystal_size_max          0.31
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_refine_diff_density_max         0.244
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_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
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_refine_ls_number_reflns         3855
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_refine_ls_R_factor_all          0.0466
_refine_ls_R_factor_gt           0.0414
_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^)+(0.0548P)^2^+0.2909P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0966
_refine_ls_wR_factor_ref         0.0994
_reflns_number_gt                3494
_reflns_number_total             3855
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol061463ysi20060614_091736.cif
_cod_data_source_block           jub1s
_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        2030.4(12)
_cod_original_sg_symbol_H-M      Cc
_cod_database_code               1506151