Switching the H-bonding network of a foldamer by modulating the backbone chirality and constitutional ratio of amino acids.
Ramesh, Veera V. E.; Vijayadas, Kuruppanthara N.; Dhokale, Snehal; Gonnade, Rajesh G.; Rajamohanan, Pattuparambil R.; Sanjayan, Gangadhar J.; Organic & biomolecular chemistry 11 (2013) 7072–7075; doi:10.1039/c3ob41369a

data_7153112
_publ_section_title
;
 Switching the H-bonding network of a foldamer by modulating the backbone
 chirality and constitutional ratio of amino acids.
;
_journal_issue                   41
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              7072
_journal_page_last               7075
_journal_paper_doi               10.1039/c3ob41369a
_journal_volume                  11
_journal_year                    2013
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C35 H38 Br N5 O6'
_chemical_formula_sum            'C35 H38 Br N5 O6'
_chemical_formula_weight         704.61
_chemical_melting_point          503
_chemical_name_common            peptide
_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                 99.774(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   11.2356(6)
_cell_length_b                   9.2098(5)
_cell_length_c                   32.8244(16)
_cell_measurement_reflns_used    9859
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      26.05
_cell_measurement_theta_min      2.30
_cell_volume                     3347.3(3)
_computing_cell_refinement       'SAINT (Bruker, 2003)'
_computing_data_collection       'SMART (Bruker, 2003)'
_computing_data_reduction        'SAINT (Bruker, 2003)'
_computing_molecular_graphics    'SHELXTL (Bruker, 2003)'
_computing_publication_material  'SHELXTL (Bruker, 2003)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       'Bruker Smart APEX II'
_diffrn_measurement_device_type  'CCD Area Detector'
_diffrn_measurement_method       'Phi and 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  0.0303
_diffrn_reflns_av_sigmaI/netI    0.0550
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       38
_diffrn_reflns_limit_l_min       -40
_diffrn_reflns_number            41276
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         1.84
_exptl_absorpt_coefficient_mu    1.281
_exptl_absorpt_correction_T_max  0.8934
_exptl_absorpt_correction_T_min  0.4675
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'bruker sadabs'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.398
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1464
_exptl_crystal_size_max          0.70
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.418
_refine_diff_density_min         -0.327
_refine_diff_density_rms         0.044
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.005(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.987
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     853
_refine_ls_number_reflns         13026
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.987
_refine_ls_R_factor_all          0.0329
_refine_ls_R_factor_gt           0.0271
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0516
_refine_ls_wR_factor_ref         0.0529
_reflns_number_gt                11766
_reflns_number_total             13026
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c3ob41369a.txt
_cod_data_source_block           comp_2b
_cod_original_sg_symbol_H-M      P21
_cod_database_code               7153112