Sequential Oxidative and Reductive Radical Cyclization Approach toward Asperparaline C and Synthesis of Its 8-Oxo Analogue.
Amatov, Tynchtyk; Pohl, Radek; Cisařová, Ivana; Jahn, Ullrich; Organic letters 19 (2017) 1152–1155; doi:10.1021/acs.orglett.7b00187

data_1545277
_publ_section_title
;
 Sequential Oxidative and Reductive Radical Cyclization Approach toward
 Asperparaline C and Synthesis of Its 8-Oxo Analogue.
;
_journal_issue                   5
_journal_name_full               'Organic letters'
_journal_page_first              1152
_journal_page_last               1155
_journal_paper_doi               10.1021/acs.orglett.7b00187
_journal_volume                  19
_journal_year                    2017
_chemical_absolute_configuration syn
_chemical_compound_source        'synthesized by the authors'
_chemical_formula_moiety         'C18 H26 N2 O4'
_chemical_formula_sum            'C18 H26 N2 O4'
_chemical_formula_weight         334.41
_space_group_IT_number           144
_space_group_name_Hall           'P 31'
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  'P 31'
_symmetry_space_group_name_H-M   'P 31'
_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                120.00
_cell_formula_units_Z            3
_cell_length_a                   9.4759(7)
_cell_length_b                   9.4759(7)
_cell_length_c                   16.7019(11)
_cell_measurement_reflns_used    7894
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      27.4357
_cell_measurement_theta_min      2.4819
_cell_volume                     1298.79(16)
_computing_cell_refinement       'SAINT V8.34A (Bruker AXS Inc., 2013)'
_computing_data_collection       'Bruker Instrument Service v2015.3.1.0'
_computing_data_reduction        'SAINT V8.34A (Bruker AXS Inc., 2013)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_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  0.0187
_diffrn_reflns_av_sigmaI/netI    0.0191
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            13253
_diffrn_reflns_theta_full        27.47
_diffrn_reflns_theta_max         27.47
_diffrn_reflns_theta_min         2.48
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.091
_exptl_absorpt_correction_T_max  0.9751
_exptl_absorpt_correction_T_min  0.9480
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS V2014/5 (Bruker AXS Inc.)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.283
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             540
_exptl_crystal_size_max          0.60
_exptl_crystal_size_mid          0.51
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.209
_refine_diff_density_min         -0.145
_refine_diff_density_rms         0.033
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.4(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.045
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     221
_refine_ls_number_reflns         3972
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0375
_refine_ls_R_factor_gt           0.0351
_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^)+(0.0614P)^2^+0.1216P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0945
_refine_ls_wR_factor_ref         0.0962
_reflns_number_gt                3757
_reflns_number_total             3972
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ol7b00187_si_003.cif
_cod_data_source_block           tsyn652_jahn
_cod_depositor_comments
'Adding full bibliography for 1545277--1545278.cif.'
_cod_original_cell_volume        1298.78(16)
_cod_database_code               1545277