Helix-forming aliphatic homo-δ-peptide foldamers based on the conformational restriction effects of cyclopropane.
Nagata, Makoto; Watanabe, Mizuki; Doi, Ryohei; Uemura, Mai; Ochiai, Nanase; Ichinose, Wataru; Fujiwara, Koichi; Sato, Yoshihiro; Kameda, Tomoshi; Takeuchi, Koh; Shuto, Satoshi; Organic & biomolecular chemistry 21 (2023) 970–980; doi:10.1039/d2ob01715f

data_7159011
_publ_section_title
;
 Helix-forming aliphatic homo-&#x3b4;-peptide foldamers based on the
 conformational restriction effects of cyclopropane.
;
_journal_issue                   5
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              970
_journal_page_last               980
_journal_paper_doi               10.1039/d2ob01715f
_journal_volume                  21
_journal_year                    2023
_chemical_absolute_configuration 'CHOOSE rm ad rmad syn or unk'
_chemical_formula_moiety         'C38 H66 N4 O8'
_chemical_formula_sum            'C38 H66 N4 O8'
_chemical_formula_weight         706.96
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_update_record
;
2020-12-10 deposited with the CCDC.	2022-11-18 downloaded from the CCDC.
;
_cell_angle_alpha                90.0000
_cell_angle_beta                 90.0000
_cell_angle_gamma                90.0000
_cell_formula_units_Z            4
_cell_length_a                   9.77455(19)
_cell_length_b                   17.1488(3)
_cell_length_c                   24.9042(5)
_cell_measurement_reflns_used    35196
_cell_measurement_temperature    133
_cell_measurement_theta_max      68.16
_cell_measurement_theta_min      3.13
_cell_volume                     4174.49(14)
_computing_cell_refinement       'RAPID AUTO'
_computing_data_collection       'RAPID AUTO (Rigaku, ????)'
_computing_data_reduction        'RAPID AUTO'
_computing_molecular_graphics    'CrystalStructure 4.2'
_computing_publication_material  'CrystalStructure 4.2 (Rigaku, 2015)'
_computing_structure_refinement  'SHELXL Version 2014/8 (Sheldrick, 2008)'
_computing_structure_solution    'SIR92 (Altomare, et al., 1994)'
_diffrn_ambient_temperature      133
_diffrn_detector_area_resol_mean 10.000
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Rigaku R-AXIS RAPID'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54187
_diffrn_reflns_av_R_equivalents  0.0333
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       29
_diffrn_reflns_limit_l_min       -29
_diffrn_reflns_number            45486
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.995
_diffrn_reflns_theta_full        67.687
_diffrn_reflns_theta_max         68.208
_diffrn_reflns_theta_min         3.129
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.632
_exptl_absorpt_correction_T_max  0.843
_exptl_absorpt_correction_T_min  0.678
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'ABSCOR (Rigaku, 1995)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.125
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1544.00
_exptl_crystal_size_max          0.350
_exptl_crystal_size_mid          0.330
_exptl_crystal_size_min          0.270
_refine_diff_density_max         0.29
_refine_diff_density_min         -0.36
_refine_ls_abs_structure_details
;
 Flack x determined using 2260 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.10(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.051
_refine_ls_hydrogen_treatment    mixed
_refine_ls_number_parameters     479
_refine_ls_number_reflns         7598
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0604
_refine_ls_R_factor_gt           0.0481
_refine_ls_shift/su_max          0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0631P)^2^+0.7252P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1172
_refine_ls_wR_factor_ref         0.1239
_reflns_Friedel_coverage         0.776
_reflns_Friedel_fraction_full    0.991
_reflns_Friedel_fraction_max     0.989
_reflns_number_gt                6343
_reflns_number_total             7598
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            d2ob01715f2.cif
_cod_data_source_block           nboctetramer
_cod_depositor_comments
'Adding full bibliography for 7159010--7159012.cif.'
_cod_original_cell_volume        4174.50(14)
_cod_database_code               7159011
_shelx_res_checksum              98998