Induction of chirality: experimental evidence of atropisomerism in azapeptides
Philipp A. Ottersbach; Gregor Schnakenburg; Michael Gutschow; Chem.Commun. 48 (2012) 5772–; doi:10.1039/c2cc31161e

data_7107768
_publ_section_title
;
 Induction of chirality: experimental evidence of atropisomerism in
 azapeptides
;
_journal_name_full               Chem.Commun.
_journal_page_first              5772
_journal_paper_doi               10.1039/c2cc31161e
_journal_volume                  48
_journal_year                    2012
_chemical_formula_moiety         'C13 H18 N4 O4'
_chemical_formula_sum            'C13 H18 N4 O4'
_chemical_formula_weight         294.31
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_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
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 92.741(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.4949(12)
_cell_length_b                   7.7324(8)
_cell_length_c                   14.7304(16)
_cell_measurement_reflns_used    4907
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      29.64
_cell_measurement_theta_min      2.77
_cell_volume                     1421.6(3)
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.33333
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker X8-KappaApexII'
_diffrn_measurement_method       'fine slicing \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  0.0392
_diffrn_reflns_av_sigmaI/netI    0.0308
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            15892
_diffrn_reflns_theta_full        28.00
_diffrn_reflns_theta_max         28.00
_diffrn_reflns_theta_min         3.26
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.104
_exptl_absorpt_correction_T_max  0.9959
_exptl_absorpt_correction_T_min  0.9675
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS 2008/1'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.375
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             624
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.270
_refine_diff_density_min         -0.225
_refine_diff_density_rms         0.046
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     204
_refine_ls_number_reflns         3426
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0524
_refine_ls_R_factor_gt           0.0389
_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^)+(0.0451P)^2^+0.5683P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0939
_refine_ls_wR_factor_ref         0.1016
_reflns_number_gt                2750
_reflns_number_total             3426
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            c2cc31161e.txt
_cod_data_source_block           Greg1405f
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               7107768