β-Turn Preferences Induced by 2,3-Methanophenylalanine Chirality
A. I. Jiménez; C. Cativiela; A. Aubry; M. Marraud; Journal of the American Chemical Society 120 (1998) 9452–9459; doi:10.1021/ja9807439

data_4116837
_publ_section_title
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 \b-Turn Preferences Induced by 2,3-Methanophenylalanine Chirality
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_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              9452
_journal_page_last               9459
_journal_paper_doi               10.1021/ja9807439
_journal_volume                  120
_journal_year                    1998
_chemical_formula_sum            'C22 H31 Cl2 N3 O4'
_chemical_formula_weight         472.40
_chemical_name_systematic
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 [Boc-S-Pro-(2R,3S)-2,3-methanophenylalanine-NHMe] dichloromethane solvate 
;
_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
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   10.1270(10)
_cell_length_b                   13.033(3)
_cell_length_c                   19.130(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30
_cell_measurement_theta_min      20
_cell_volume                     2524.9(7)
_computing_publication_material  SHELXL-93
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    SIR92
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'Nonius CAD-4 four circle diffractometer'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54056
_diffrn_reflns_av_R_equivalents  0.0760
_diffrn_reflns_av_sigmaI/netI    0.0136
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       51
_diffrn_reflns_limit_k_min       -2
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            2537
_diffrn_reflns_theta_max         69.82
_diffrn_reflns_theta_min         4.10
_diffrn_standards_decay_%        0
_diffrn_standards_interval_time  90
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    2.569
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.243
_exptl_crystal_description       'Transparent prism'
_exptl_crystal_F_000             1000
_refine_diff_density_max         .248
_refine_diff_density_min         -.255
_refine_diff_density_rms         .045
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.10(7)
_refine_ls_extinction_coef       0.0009(4)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^l^3^/sin(2q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_all   0.925
_refine_ls_goodness_of_fit_obs   0.951
_refine_ls_matrix_type           full
_refine_ls_number_parameters     289
_refine_ls_number_reflns         2424
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.095
_refine_ls_restrained_S_obs      0.951
_refine_ls_R_factor_all          0.0846
_refine_ls_R_factor_obs          0.0621
_refine_ls_shift/esd_max         0.004
_refine_ls_shift/esd_mean        0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[s^2^(Fo^2^)+( 0.1322P)^2^+0.8807P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.2255
_refine_ls_wR_factor_obs         0.1698
_reflns_number_observed          1857
_reflns_number_total             2474
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ja9807439_3.cif
_cod_data_source_block           peptide3a
_cod_depositor_comments
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The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w=1/[s^2^(Fo^2^)+(
0.1322P)^2^+0.8807P] where P=(Fo^2^+2Fc^2^)/3' was changed to 'calc'.
New tag '_refine_ls_weighting_details' was created. The value of the
new tag was set to 'w=1/[s^2^(Fo^2^)+( 0.1322P)^2^+0.8807P] where
P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
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_cod_original_formula_sum        'C21 H29 N3 O4 . C H2 Cl2'
_cod_database_code               4116837