Crystallographic Characterization of Helical Secondary Structures in α/β-Peptides with 1:1 Residue Alternation
Soo Hyuk Choi; Ilia A. Guzei; Lara C. Spencer; Samuel H. Gellman; Journal of the American Chemical Society 130 (2008) 6544–6550; doi:10.1021/ja800355p

data_4107791
_publ_contact_author_address
;
Department of Chemistry
University of Wisconsin-Madison
1101 University Ave
Madison, WI  53706
USA
;
_publ_contact_author_email       iguzei@chem.wisc.edu
_publ_contact_author_fax         608-262-0381
_publ_contact_author_name
;
Guzei, Ilia A. 
;
_publ_contact_author_phone       608-263-4694
_publ_section_title
;
 Crystallographic Characterization of Helical Secondary Structures in
 \a/\b-Peptides with 1:1 Residue Alternation
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6544
_journal_page_last               6550
_journal_paper_doi               10.1021/ja800355p
_journal_volume                  130
_journal_year                    2008
_chemical_formula_sum            'C32 H48 N4 O7'
_chemical_formula_weight         600.74
_space_group_IT_number           170
_symmetry_cell_setting           hexagonal
_symmetry_space_group_name_Hall  'P 65'
_symmetry_space_group_name_H-M   'P 65'
_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            6
_cell_length_a                   11.1738(2)
_cell_length_b                   11.1738(2)
_cell_length_c                   46.6887(16)
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      26.36
_cell_measurement_theta_min      2.15
_cell_volume                     5048.3(2)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0283
_diffrn_reflns_av_sigmaI/netI    0.0181
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       57
_diffrn_reflns_limit_l_min       -58
_diffrn_reflns_number            42086
_diffrn_reflns_theta_full        26.38
_diffrn_reflns_theta_max         26.38
_diffrn_reflns_theta_min         2.10
_exptl_absorpt_coefficient_mu    0.084
_exptl_absorpt_correction_T_max  0.9705
_exptl_absorpt_correction_T_min  0.9657
_exptl_absorpt_correction_type   none
_exptl_crystal_density_diffrn    1.186
_exptl_crystal_density_meas      0
_exptl_crystal_F_000             1944
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.39
_exptl_crystal_size_min          0.36
_refine_diff_density_max         0.348
_refine_diff_density_min         -0.216
_refine_diff_density_rms         0.031
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.0(6)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.032
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     395
_refine_ls_number_reflns         6844
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0346
_refine_ls_R_factor_gt           0.0325
_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^)+(0.0568P)^2^+0.8133P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0881
_refine_ls_wR_factor_ref         0.0903
_reflns_number_gt                6556
_reflns_number_total             6844
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja800355p-file002.cif
_cod_data_source_block           gellman27
_cod_database_code               4107791