Cis-Trans Amide Bond Rotamers in β-Peptoids and Peptoids: Evaluation of Stereoelectronic Effects in Backbone and Side Chains
Jonas S. Laursen; Jens Engel-Andreasen; Peter Fristrup; Pernille Harris; Christian A. Olsen; Journal of the American Chemical Society 135 (2013) 2835–2844; doi:10.1021/ja312532x

data_4119375
_publ_section_title
;
 Cis-Trans Amide Bond Rotamers in \b-Peptoids and Peptoids: Evaluation of
 Stereoelectronic Effects in Backbone and Side Chains
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              2835
_journal_page_last               2844
_journal_paper_doi               10.1021/ja312532x
_journal_volume                  135
_journal_year                    2013
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C21 H26 N2 O S'
_chemical_formula_sum            'C21 H26 N2 O S'
_chemical_formula_weight         354.50
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.162(2)
_cell_length_b                   10.857(2)
_cell_length_c                   17.358(4)
_cell_measurement_reflns_used    8102
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      28.053
_cell_measurement_theta_min      2.322
_cell_volume                     1915.1(7)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker SMART platform ccd'
_diffrn_measurement_method       'profile data from \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  0.0403
_diffrn_reflns_av_sigmaI/netI    0.0345
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            20046
_diffrn_reflns_theta_full        28.23
_diffrn_reflns_theta_max         28.23
_diffrn_reflns_theta_min         2.21
_exptl_absorpt_coefficient_mu    0.180
_exptl_absorpt_correction_T_max  1.0
_exptl_absorpt_correction_T_min  0.94
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS, Bruker (2000)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.230
_exptl_crystal_description       rod
_exptl_crystal_F_000             760
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.416
_refine_diff_density_min         -0.328
_refine_diff_density_rms         0.071
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.06(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.017
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     228
_refine_ls_number_reflns         4503
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.017
_refine_ls_R_factor_all          0.0566
_refine_ls_R_factor_gt           0.0494
_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^)+(0.1094P)^2^+0.4826P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1391
_refine_ls_wR_factor_ref         0.1587
_reflns_number_gt                4105
_reflns_number_total             4503
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja312532x_si_004.cif
_cod_data_source_block           JEA134
_cod_original_cell_volume        1915.0(7)
_cod_database_code               4119375