N- versus C-Terminal Control over the Screw-Sense Preference of the Configurationally Achiral, Conformationally Helical Peptide Motif Aib8GlyAib8
Jordi Solà; Madeleine Helliwell; Jonathan Clayden; Journal of the American Chemical Society 132 (2010) 4548–4549; doi:10.1021/ja100662d

data_4102218
_publ_contact_author
; 
    Madeleine Helliwell 
;
_publ_section_title
;
 N- versus C-Terminal Control over the Screw-Sense Preference of the
 Configurationally Achiral, Conformationally Helical Peptide Motif
 Aib8GlyAib8
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              4548
_journal_page_last               4549
_journal_paper_doi               10.1021/ja100662d
_journal_volume                  132
_journal_year                    2010
_chemical_absolute_configuration syn
_chemical_formula_sum            'C87 H140 N18 O21'
_chemical_formula_weight         1774.17
_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                   16.340(3)
_cell_length_b                   17.121(3)
_cell_length_c                   36.538(7)
_cell_measurement_reflns_used    963
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      24.11
_cell_measurement_theta_min      2.40
_cell_volume                     10222(3)
_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 0.999
_diffrn_measured_fraction_theta_max 0.999
_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  0.0610
_diffrn_reflns_av_sigmaI/netI    0.0444
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       36
_diffrn_reflns_limit_l_min       -36
_diffrn_reflns_number            49807
_diffrn_reflns_theta_full        20.81
_diffrn_reflns_theta_max         20.81
_diffrn_reflns_theta_min         1.72
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.153
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             3824
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.268
_refine_diff_density_min         -0.209
_refine_diff_density_rms         0.050
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.155
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1224
_refine_ls_number_reflns         10692
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.154
_refine_ls_R_factor_all          0.0767
_refine_ls_R_factor_gt           0.0725
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0336P)^2^+21.1132P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1474
_refine_ls_wR_factor_ref         0.1493
_reflns_number_gt                10099
_reflns_number_total             10692
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja100662d_si_002.cif
_cod_data_source_block           s3325m
_cod_database_code               4102218