Effect of Side Chains on Turns and Helices in Peptides of β3-Aminoxy Acids
Dan Yang; Yu-Hui Zhang; Bing Li; Dan-Wei Zhang; Jenny Chun-Yu Chan; Nian-Yong Zhu; Shi-Wei Luo; Yun-Dong Wu; Journal of the American Chemical Society 126 (2004) 6956–6966; doi:10.1021/ja049976s

data_4112658
_publ_section_title
;
 Effect of Side Chains on Turns and Helices in Peptides of \b3-Aminoxy
 Acids
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6956
_journal_page_last               6966
_journal_paper_doi               10.1021/ja049976s
_journal_volume                  126
_journal_year                    2004
_chemical_formula_moiety         'C18 H34 N2 O3'
_chemical_formula_sum            'C18 H34 N2 O3'
_chemical_formula_weight         326.47
_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                   10.225(2)
_cell_length_b                   11.534(2)
_cell_length_c                   18.169(4)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    253(2)
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     2142.8(7)
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      253(2)
_diffrn_measured_fraction_theta_full 0.699
_diffrn_measured_fraction_theta_max 0.699
_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  0.0439
_diffrn_reflns_av_sigmaI/netI    0.0772
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            6348
_diffrn_reflns_theta_full        23.23
_diffrn_reflns_theta_max         23.23
_diffrn_reflns_theta_min         2.09
_exptl_absorpt_coefficient_mu    0.068
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.012
_exptl_crystal_description       prism
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.251
_refine_diff_density_min         -0.187
_refine_diff_density_rms         0.059
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -2(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.963
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     253
_refine_ls_number_reflns         1973
_refine_ls_number_restraints     7
_refine_ls_restrained_S_all      0.963
_refine_ls_R_factor_all          0.0729
_refine_ls_R_factor_gt           0.0473
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0781P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1249
_refine_ls_wR_factor_ref         0.1330
_reflns_number_gt                1357
_reflns_number_total             1973
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja049976ssi20040101_113754_4.cif
_cod_data_source_block           compound6
_cod_database_code               4112658