Local versus Global Control of Helical Folding in β-Peptide Segments Using Hydrazino Turns.
Imani, Zeynab; Guillot, Régis; Declerck, Valérie; Aitken, David J.; The Journal of organic chemistry 85 (2020) 6165–6171; doi:10.1021/acs.joc.0c00305

data_4038268
_publ_section_title
;
 Local versus Global Control of Helical Folding in \b-Peptide Segments
 Using Hydrazino Turns.
;
_journal_issue                   9
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              6165
_journal_page_last               6171
_journal_paper_doi               10.1021/acs.joc.0c00305
_journal_volume                  85
_journal_year                    2020
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C32 H50 N8 O7, C H Cl3'
_chemical_formula_sum            'C33 H51 Cl3 N8 O7'
_chemical_formula_weight         778.16
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     difmap
_audit_creation_method           SHELXL-2018/3
_cell_angle_alpha                90
_cell_angle_beta                 90.605(2)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   9.5008(3)
_cell_length_b                   19.9938(7)
_cell_length_c                   10.2841(4)
_cell_measurement_reflns_used    9946
_cell_measurement_temperature    100(1)
_cell_measurement_theta_max      65.16
_cell_measurement_theta_min      4.30
_cell_volume                     1953.43(12)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX3'
_computing_data_reduction        'Bruker SAINT'
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      100(1)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker VENTURE PHOTON100 CMOS'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0398
_diffrn_reflns_av_unetI/netI     0.0347
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            26788
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        65.249
_diffrn_reflns_theta_max         65.249
_diffrn_reflns_theta_min         4.299
_exptl_absorpt_coefficient_mu    2.583
_exptl_absorpt_correction_T_max  0.9526
_exptl_absorpt_correction_T_min  0.8087
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'apex3 Bruker'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.323
_exptl_crystal_description       plate
_exptl_crystal_F_000             824
_exptl_crystal_size_max          0.180
_exptl_crystal_size_mid          0.150
_exptl_crystal_size_min          0.040
_refine_diff_density_max         0.446
_refine_diff_density_min         -0.610
_refine_diff_density_rms         0.055
_refine_ls_abs_structure_details
;
 Flack x determined using 2939 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.060(5)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.036
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     463
_refine_ls_number_reflns         6651
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.036
_refine_ls_R_factor_all          0.0453
_refine_ls_R_factor_gt           0.0437
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0712P)^2^+1.0977P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1180
_refine_ls_wR_factor_ref         0.1195
_reflns_Friedel_coverage         0.928
_reflns_Friedel_fraction_full    0.988
_reflns_Friedel_fraction_max     0.988
_reflns_number_gt                6416
_reflns_number_total             6651
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo0c00305_si_002.cif
_cod_data_source_block           2
_cod_depositor_comments          'Adding full bibliography for 4038268.cif.'
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4038268
_shelx_estimated_absorpt_t_min   0.658
_shelx_estimated_absorpt_t_max   0.905
_shelx_res_checksum              40197
_shelx_hkl_checksum              20997