Engineering the Structure of an N-Terminal β-Turn To Maximize Screw-Sense Preference in Achiral Helical Peptide Chains.
De Poli, Matteo; Byrne, Liam; Brown, Robert A.; Solà, Jordi; Castellanos, Alejandro; Boddaert, Thomas; Wechsel, Romina; Beadle, Jonathan D.; Clayden, Jonathan; The Journal of organic chemistry 79 (2014) 4659–4675; doi:10.1021/jo500714b

data_4029370
_publ_section_title
;
 Engineering the Structure of an N-Terminal \b-Turn To Maximize
 Screw-Sense Preference in Achiral Helical Peptide Chains.
;
_journal_issue                   10
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              4659
_journal_page_last               4675
_journal_paper_doi               10.1021/jo500714b
_journal_volume                  79
_journal_year                    2014
_chemical_absolute_configuration syn
_chemical_formula_sum            'C27 H52 N8 O8'
_chemical_formula_weight         616.77
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 108.615(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   11.5859(5)
_cell_length_b                   9.5850(4)
_cell_length_c                   16.5938(8)
_cell_measurement_reflns_used    5197
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      70.29
_cell_measurement_theta_min      4.03
_cell_volume                     1746.35(14)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0379
_diffrn_reflns_av_sigmaI/netI    0.0537
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            8679
_diffrn_reflns_theta_full        66.60
_diffrn_reflns_theta_max         70.29
_diffrn_reflns_theta_min         2.81
_exptl_absorpt_coefficient_mu    0.719
_exptl_absorpt_correction_T_max  0.9123
_exptl_absorpt_correction_T_min  0.692733
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            white
_exptl_crystal_density_diffrn    1.173
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             668
_exptl_crystal_size_max          0.29
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.13
_refine_diff_density_max         0.257
_refine_diff_density_min         -0.335
_refine_diff_density_rms         0.049
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.01(18)
_refine_ls_extinction_coef       0.0020(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.117
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     417
_refine_ls_number_reflns         5507
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.117
_refine_ls_R_factor_all          0.0476
_refine_ls_R_factor_gt           0.0447
_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^)+(0.0668P)^2^+0.0794P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1186
_refine_ls_wR_factor_ref         0.1204
_reflns_number_gt                5135
_reflns_number_total             5507
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo500714b_si_005.cif
_cod_data_source_block           s3935ma
_cod_depositor_comments
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The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 

 Adding full bibliography for 4029365--4029371.cif.
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_cod_original_cell_volume        1746.35(13)
_cod_original_sg_symbol_H-M      P2(1)
_cod_database_code               4029370