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_4119373
_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_formula_moiety         'C22 H27 N O3'
_chemical_formula_sum            'C22 H27 N O3'
_chemical_formula_weight         353.45
_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                 102.82(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.0851(18)
_cell_length_b                   19.077(4)
_cell_length_c                   11.883(2)
_cell_measurement_reflns_used    3026
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      21.859
_cell_measurement_theta_min      2.535
_cell_volume                     2008.2(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 0.997
_diffrn_measured_fraction_theta_max 0.997
_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  0.0627
_diffrn_reflns_av_sigmaI/netI    0.0463
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -25
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            27656
_diffrn_reflns_theta_full        28.32
_diffrn_reflns_theta_max         28.32
_diffrn_reflns_theta_min         2.06
_exptl_absorpt_coefficient_mu    0.077
_exptl_absorpt_correction_T_max  1.0
_exptl_absorpt_correction_T_min  0.85
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS, Bruker (2000)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.169
_exptl_crystal_description       plate
_exptl_crystal_F_000             760
_exptl_crystal_size_max          0.17
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.252
_refine_diff_density_min         -0.245
_refine_diff_density_rms         0.051
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.038
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     239
_refine_ls_number_reflns         4984
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.038
_refine_ls_R_factor_all          0.0848
_refine_ls_R_factor_gt           0.0511
_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^)+(0.0375P)^2^+0.8885P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1023
_refine_ls_wR_factor_ref         0.1235
_reflns_number_gt                3443
_reflns_number_total             4984
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja312532x_si_002.cif
_cod_data_source_block           isla1m_abs
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4119373