A new peptide motif in the formation of supramolecular double helices
Poulami Jana; Sibaprasad Maity; Suman Kumar Maity; Debasish Haldar; Chem.Commun. 47 (2011) 2092–; doi:10.1039/c0cc04244g

data_7105967
_publ_section_title
;
 A new peptide motif in the formation of supramolecular double helices
;
_journal_name_full               Chem.Commun.
_journal_page_first              2092
_journal_paper_doi               10.1039/c0cc04244g
_journal_volume                  47
_journal_year                    2011
_chemical_formula_sum            'C25 H39 N3 O7'
_chemical_formula_weight         493.59
_space_group_IT_number           19
_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                   10.6501(5)
_cell_length_b                   14.1442(5)
_cell_length_c                   18.3996(8)
_cell_measurement_temperature    296(2)
_cell_volume                     2771.7(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_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  0.0499
_diffrn_reflns_av_sigmaI/netI    0.0320
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            20889
_diffrn_reflns_theta_full        22.77
_diffrn_reflns_theta_max         22.77
_diffrn_reflns_theta_min         1.82
_exptl_absorpt_coefficient_mu    0.086
_exptl_crystal_density_diffrn    1.183
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1064
_refine_diff_density_max         0.223
_refine_diff_density_min         -0.151
_refine_diff_density_rms         0.032
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.4(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.893
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     325
_refine_ls_number_reflns         3756
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.893
_refine_ls_R_factor_all          0.0443
_refine_ls_R_factor_gt           0.0366
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0867P)^2^+0.4298P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1002
_refine_ls_wR_factor_ref         0.1110
_reflns_number_gt                3351
_reflns_number_total             3756
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            C0CC04244G.TXT
_cod_data_source_block           YUL
_cod_database_code               7105967