Hybrid Peptide Design. Hydrogen Bonded Conformations in Peptides Containing the Stereochemically Constrained γ-Amino Acid Residue, Gabapentin
Prema G. Vasudev; Kuppanna Ananda; Sunanda Chatterjee; Subrayashastry Aravinda; Narayanaswamy Shamala; Padmanabhan Balaram; Journal of the American Chemical Society 129 (2007) 4039–4048; doi:10.1021/ja068910p

data_4109265
_publ_section_title
;
 Hybrid Peptide Design. Hydrogen Bonded Conformations in Peptides
 Containing the Stereochemically Constrained \g-Amino Acid Residue,
 Gabapentin
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              4039
_journal_page_last               4048
_journal_paper_doi               10.1021/ja068910p
_journal_volume                  129
_journal_year                    2007
_chemical_formula_moiety         'C32 H56 N4 O7'
_chemical_formula_sum            'C32 H56 N4 O7'
_chemical_formula_weight         608.81
_chemical_name_common            Boc-Gpn-Aib-Gpn-Aib-OMe
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/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                 109.256(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   30.027(4)
_cell_length_b                   12.1823(18)
_cell_length_c                   20.453(3)
_cell_measurement_temperature    293(2)
_cell_volume                     7063.1(17)
_computing_data_collection       SMART
_computing_data_reduction        SAINT
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.922
_diffrn_measured_fraction_theta_max 0.922
_diffrn_measurement_device_type  'BRUKER AXS SMART APEX CCD with Mo source'
_diffrn_measurement_method       'omega scan'
_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  0.0282
_diffrn_reflns_av_sigmaI/netI    0.0286
_diffrn_reflns_limit_h_max       37
_diffrn_reflns_limit_h_min       -38
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            26028
_diffrn_reflns_theta_full        26.97
_diffrn_reflns_theta_max         26.97
_diffrn_reflns_theta_min         1.44
_exptl_absorpt_coefficient_mu    0.080
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.145
_exptl_crystal_description       Rectangular
_exptl_crystal_F_000             2656
_exptl_crystal_size_max          0.50
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.284
_refine_diff_density_min         -0.221
_refine_diff_density_rms         0.055
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     404
_refine_ls_number_reflns         7094
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.0887
_refine_ls_R_factor_gt           0.0694
_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^)+(0.0944P)^2^+13.3656P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2053
_refine_ls_wR_factor_ref         0.2177
_reflns_number_gt                5409
_reflns_number_total             7094
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja068910psi20061213_093822.cif
_cod_data_source_block           gpnu4
_cod_original_cell_volume        7062.9(18)
_cod_database_code               4109265