Reversal of H-bonding direction by N-sulfonation in a synthetic reverse-turn peptide motif.
Vijayadas, Kuruppanthara N.; Kotmale, Amol S.; Thorat, Shridhar H.; Gonnade, Rajesh G.; Nair, Roshna V.; Rajamohanan, Pattuparambil R.; Sanjayan, Gangadhar J.; Organic & biomolecular chemistry 13 (2015) 3064–3069; doi:10.1039/c4ob02438a

data_7154289
_publ_section_title
;
 Reversal of H-bonding direction by N-sulfonation in a synthetic
 reverse-turn peptide motif.
;
_journal_issue                   10
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3064
_journal_page_last               3069
_journal_paper_doi               10.1039/c4ob02438a
_journal_volume                  13
_journal_year                    2015
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C27 H33 Br N4 O5 S'
_chemical_formula_sum            'C27 H33 Br N4 O5 S'
_chemical_formula_weight         605.54
_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
_audit_update_record
;
2014-09-27 deposited with the CCDC.
2015-01-13 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.7186(2)
_cell_length_b                   15.8096(5)
_cell_length_c                   26.5176(7)
_cell_measurement_reflns_used    3356
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      22.33
_cell_measurement_theta_min      2.58
_cell_volume                     2816.66(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      296(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_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           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0849
_diffrn_reflns_av_sigmaI/netI    0.1139
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       35
_diffrn_reflns_limit_l_min       -35
_diffrn_reflns_number            25564
_diffrn_reflns_theta_full        28.29
_diffrn_reflns_theta_max         28.29
_diffrn_reflns_theta_min         2.58
_exptl_absorpt_coefficient_mu    1.577
_exptl_absorpt_correction_T_max  0.6406
_exptl_absorpt_correction_T_min  0.5121
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Bruker SADABS'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.428
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1256
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: Ethyl Acetate - Petroleum Ether'
_exptl_crystal_size_max          0.49
_exptl_crystal_size_mid          0.42
_exptl_crystal_size_min          0.31
_refine_diff_density_max         0.475
_refine_diff_density_min         -0.468
_refine_diff_density_rms         0.086
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.039(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.067
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     346
_refine_ls_number_reflns         6952
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.067
_refine_ls_R_factor_all          0.1125
_refine_ls_R_factor_gt           0.0698
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0357P)^2^+0.2245P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1008
_refine_ls_wR_factor_ref         0.1124
_reflns_number_gt                4854
_reflns_number_total             6952
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c4ob02438a2.cif
_cod_data_source_block           1
_cod_depositor_comments
'Adding full bibliography for 7154289--7154295.cif.'
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7154289