How mithramycin stereochemistry dictates its structure and DNA binding function.
Hou, Caixia; Rohr, Jürgen; Parkin, Sean; Tsodikov, Oleg V.; MedChemComm 10 (2019) 735–741; doi:10.1039/c9md00100j

data_7123231
_publ_section_title
;
 How mithramycin stereochemistry dictates its structure and DNA binding
 function.
;
_journal_issue                   5
_journal_name_full               MedChemComm
_journal_page_first              735
_journal_page_last               741
_journal_paper_doi               10.1039/c9md00100j
_journal_volume                  10
_journal_year                    2019
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C416 H544 B8 O197 Zn4, 60(O)'
_chemical_formula_sum            'C416 H544 B8 O257 Zn4'
_chemical_formula_weight         10004.44
_chemical_name_systematic        mtm-B-Zn2+
_space_group_crystal_system      orthorhombic
_space_group_IT_number           23
_space_group_name_Hall           'I 2 2'
_space_group_name_H-M_alt        'I 2 2 2'
_symmetry_space_group_name_Hall  'I 2 2'
_symmetry_space_group_name_H-M   'I 2 2 2'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2019-02-12 deposited with the CCDC.    2019-03-28 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            1
_cell_length_a                   18.7382(5)
_cell_length_b                   28.3032(8)
_cell_length_c                   31.3664(7)
_cell_measurement_reflns_used    9305
_cell_measurement_temperature    90.0(2)
_cell_measurement_theta_max      58.49
_cell_measurement_theta_min      2.75
_cell_volume                     16635.2(7)
_computing_cell_refinement       '<i>APEX2</i> (Bruker-AXS, 2006)'
_computing_data_collection       '<i>APEX2</i> (Bruker-AXS, 2006)'
_computing_data_reduction        '<i>APEX2</i> (Bruker-AXS, 2006)'
_computing_molecular_graphics    '<i>XP in SHELXTL</i> (Sheldrick, 2008)'
_computing_publication_material
'<i>SHELX</i> (Sheldrick, 2008) and <i>CIFFIX</i> (Parkin, 2013)'
_computing_structure_refinement  '<i>SHELXL-2018/3</i> (Sheldrick, 2015b)'
_computing_structure_solution    '<i>SHELXT</i> (Sheldrick, 2015a)'
_diffrn_ambient_temperature      90.0(2)
_diffrn_detector_area_resol_mean 5.6
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker X8 Proteum diffractometer'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0783
_diffrn_reflns_av_unetI/netI     0.0395
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       28
_diffrn_reflns_limit_k_min       -34
_diffrn_reflns_limit_l_max       29
_diffrn_reflns_limit_l_min       -37
_diffrn_reflns_number            167676
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.485
_diffrn_reflns_theta_min         2.747
_diffrn_source                   'fine-focus rotating anode'
_exptl_absorpt_coefficient_mu    0.850
_exptl_absorpt_correction_T_max  0.929
_exptl_absorpt_correction_T_min  0.786
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '<i>SADABS</i> (Krause et al., 2015)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    0.999
_exptl_crystal_description       block
_exptl_crystal_F_000             5256
_exptl_crystal_recrystallization_method 'Hanging drop'
_exptl_crystal_size_max          0.160
_exptl_crystal_size_mid          0.150
_exptl_crystal_size_min          0.100
_refine_diff_density_max         0.543
_refine_diff_density_min         -0.444
_refine_diff_density_rms         0.055
_refine_ls_abs_structure_details
; 
Flack 'x' determined using 4582 quotients [(I+)-(I-)]/[(I+)+(I-)] 
[Parsons, Flack and Wagner (2013)]. 
;
_refine_ls_abs_structure_Flack   0.030(11)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     859
_refine_ls_number_reflns         15202
_refine_ls_number_restraints     51
_refine_ls_restrained_S_all      1.051
_refine_ls_R_factor_all          0.0693
_refine_ls_R_factor_gt           0.0508
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1059P)^2^+0.4945P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1413
_refine_ls_wR_factor_ref         0.1590
_reflns_Friedel_coverage         0.854
_reflns_Friedel_fraction_full    0.994
_reflns_Friedel_fraction_max     0.989
_reflns_number_gt                12093
_reflns_number_total             15202
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c9md00100j1.cif
_cod_data_source_block           x15261xsq
_cod_depositor_comments
'Adding full bibliography for 7123230--7123231.cif.'
_cod_database_code               7123231
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_min   0.876
_shelx_estimated_absorpt_t_max   0.920
_exptl_absorpt_special_details
; 
In addition to absorption, multi-scan techniques also correct other slowly 
varying changes in scale factor over reciprocal space, such as those caused 
by x-ray beam inhomogeneity, goniometer imperfection, crystal decomposition, 
crystal longer than the x-ray beam cross section, absorption by the crystal 
mount etc.  These account, by and large, for much of the difference between 
estimated values of Tmin and Tmax and the _exptl_absorpt_correction_ values. 
;
_shelx_res_checksum              7370
_shelx_fab_checksum              85158