Structural effects of proline substitution and metal binding on hexameric cyclic peptoids.
Izzo, Irene; Ianniello, Graziella; De Cola, Chiara; Nardone, Brunello; Erra, Loredana; Vaughan, Gavin; Tedesco, Consiglia; De Riccardis, Francesco; Organic letters 15 (2013) 598–601; doi:10.1021/ol3034143

data_1508893
_publ_section_title
;
 Structural effects of proline substitution and metal binding on hexameric
 cyclic peptoids.
;
_journal_issue                   3
_journal_name_full               'Organic letters'
_journal_page_first              598
_journal_page_last               601
_journal_paper_doi               10.1021/ol3034143
_journal_volume                  15
_journal_year                    2013
_chemical_absolute_configuration syn
_chemical_formula_moiety         'Na4 C92 H147 N19 O27 4+, 4(PF6-), 3(C2H3N)'
_chemical_formula_sum            'C98 H156 F24 N22 Na4 O27 P4'
_chemical_formula_weight         2746.29
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           146
_symmetry_cell_setting           trigonal
_symmetry_space_group_name_Hall  'R 3'
_symmetry_space_group_name_H-M   'R 3 :H'
_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                120.00
_cell_formula_units_Z            3
_cell_length_a                   16.382(5)
_cell_length_b                   16.382(5)
_cell_length_c                   39.89(2)
_cell_measurement_reflns_used    11518
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      12.55
_cell_measurement_theta_min      1.05
_cell_volume                     9271(6)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR-2002 (Burla et al.,2003)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.938
_diffrn_measured_fraction_theta_max 0.938
_diffrn_radiation_source         synchrotron
_diffrn_radiation_wavelength     0.30060
_diffrn_reflns_av_R_equivalents  0.0858
_diffrn_reflns_av_sigmaI/netI    0.0756
_diffrn_reflns_limit_h_max       23
_diffrn_reflns_limit_h_min       -23
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       56
_diffrn_reflns_limit_l_min       -55
_diffrn_reflns_number            30670
_diffrn_reflns_theta_full        12.55
_diffrn_reflns_theta_max         12.55
_diffrn_reflns_theta_min         1.05
_exptl_absorpt_coefficient_mu    0.016
_exptl_absorpt_correction_T_max  0.967
_exptl_absorpt_correction_T_min  0.921
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Blessing, 1995'
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.476
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'hexagonal prism'
_exptl_crystal_F_000             4302
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.141
_refine_diff_density_min         -0.594
_refine_diff_density_rms         0.086
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.8(3)
_refine_ls_extinction_coef       2.07(17)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   2.290
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     519
_refine_ls_number_reflns         11518
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      2.289
_refine_ls_R_factor_all          0.1481
_refine_ls_R_factor_gt           0.1436
_refine_ls_shift/su_max          0.147
_refine_ls_shift/su_mean         0.025
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.2000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.4399
_refine_ls_wR_factor_ref         0.4850
_reflns_number_gt                10356
_reflns_number_total             11518
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol3034143_si_001.cif
_cod_data_source_block           new16
_cod_original_sg_symbol_H-M      'R 3'
_cod_database_code               1508893