A Synthetic Zipper Peptide Motif Orchestrated via Co-operative Interplay of Hydrogen Bonding, Aromatic Stacking, and Backbone Chirality
Roshna V. Nair; Sanjeev Kheria; Suresh Rayavarapu; Amol S. Kotmale; Bharatam Jagadeesh; Rajesh G. Gonnade; Vedavati G. Puranik; Pattuparambil R. Rajamohanan; Gangadhar J. Sanjayan; Journal of the American Chemical Society 135 (2013) 11477–11480; doi:10.1021/ja405455g

data_4120239
_publ_section_title
;
 A Synthetic Zipper Peptide Motif Orchestrated via Co-operative Interplay
 of Hydrogen Bonding, Aromatic Stacking, and Backbone Chirality
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              11477
_journal_page_last               11480
_journal_paper_doi               10.1021/ja405455g
_journal_volume                  135
_journal_year                    2013
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C44 H47 N7 O7.2(H2O)'
_chemical_formula_sum            'C44 H51 N7 O9'
_chemical_formula_weight         821.92
_chemical_name_common            foldamers
_chemical_name_systematic
; 
 ? 
;
_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                   10.2506(5)
_cell_length_b                   19.2039(9)
_cell_length_c                   21.4853(10)
_cell_measurement_reflns_used    5607
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      21.705
_cell_measurement_theta_min      2.201
_cell_volume                     4229.4(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), platon'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device       'Bruker Smart APEX'
_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  0.0487
_diffrn_reflns_av_sigmaI/netI    0.0538
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            21448
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.90
_exptl_absorpt_coefficient_mu    0.092
_exptl_absorpt_correction_T_max  0.9915
_exptl_absorpt_correction_T_min  0.9600
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Bruker SADABS'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.291
_exptl_crystal_description       needle
_exptl_crystal_F_000             1744
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.19
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.308
_refine_diff_density_min         -0.208
_refine_diff_density_rms         0.053
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -1.2(18)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.348
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     563
_refine_ls_number_reflns         7422
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.348
_refine_ls_R_factor_all          0.0936
_refine_ls_R_factor_gt           0.0857
_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^)+(0.0619P)^2^+1.6085P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1797
_refine_ls_wR_factor_ref         0.1830
_reflns_number_gt                6787
_reflns_number_total             7422
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja405455g_si_002_3.cif
_cod_data_source_block           Comp_5
_cod_database_code               4120239