Homochiral G-Quadruplexes with Ba2+ but Not with K+: The Cation Programs Enantiomeric Self-Recognition
Xiaodong Shi; James C. Fettinger; Jeffery T. Davis; Journal of the American Chemical Society 123 (2001) 6738–6739; doi:10.1021/ja004330v

data_4115611
_publ_section_title
;
 Homochiral G-Quadruplexes with Ba2+ but Not with K+: The Cation Programs
 Enantiomeric Self-Recognition
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              6738
_journal_page_last               6739
_journal_paper_doi               10.1021/ja004330v
_journal_volume                  123
_journal_year                    2001
_chemical_formula_sum            'C176.38 H281 Ba N52 O59.5 Si8'
_chemical_formula_weight         4444.09
_chemical_name_systematic
;
 ?
;
_space_group_IT_number           79
_symmetry_cell_setting           tetragonal
_symmetry_space_group_name_Hall  'I 4'
_symmetry_space_group_name_H-M   'I 4'
_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                   30.780(4)
_cell_length_b                   30.780(4)
_cell_length_c                   25.831(5)
_cell_measurement_temperature    193(2)
_cell_volume                     24473(7)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0599
_diffrn_reflns_av_sigmaI/netI    0.0412
_diffrn_reflns_limit_h_max       33
_diffrn_reflns_limit_h_min       -33
_diffrn_reflns_limit_k_max       33
_diffrn_reflns_limit_k_min       -33
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            60712
_diffrn_reflns_theta_full        22.50
_diffrn_reflns_theta_max         22.50
_diffrn_reflns_theta_min         2.09
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.283
_exptl_absorpt_correction_type   'empirical, SADABS'
_exptl_crystal_colour            Yellow
_exptl_crystal_density_diffrn    1.206
_exptl_crystal_description       Block
_exptl_crystal_F_000             9389
_exptl_crystal_size_max          0.515
_exptl_crystal_size_mid          0.255
_exptl_crystal_size_min          0.161
_refine_diff_density_max         1.126
_refine_diff_density_min         -0.549
_refine_diff_density_rms         0.095
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.18(2)
_refine_ls_extinction_coef       0.00045(6)
_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   1.057
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1261
_refine_ls_number_reflns         15958
_refine_ls_number_restraints     16
_refine_ls_restrained_S_all      1.058
_refine_ls_R_factor_all          0.0994
_refine_ls_R_factor_gt           0.0804
_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^)+(0.1162P)^2^+134.7330P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2050
_refine_ls_wR_factor_ref         0.2203
_reflns_number_gt                13697
_reflns_number_total             15958
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja004330v.cif
_cod_data_source_block           JA004330V-20-290
_cod_original_cell_volume        24472(6)
_cod_original_formula_sum        'C176.38 H281 Ba N52 O59.50 Si8'
_cod_database_code               4115611