Comprehensive Structural Studies of 2',3'-Difluorinated Nucleosides: Comparison of Theory, Solution, and Solid State
Joseph J. Barchi; Rajeshri G. Karki; Marc C. Nicklaus; Maqbool A. Siddiqui; Clifford George; Igor A. Mikhailopulo; Victor E. Marquez; Journal of the American Chemical Society 130 (2008) 9048–9057; doi:10.1021/ja800964g

data_4108017
_publ_section_title
;
 Comprehensive Structural Studies of 2',3'-Difluorinated Nucleosides:
 Comparison of Theory, Solution, and Solid State
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              9048
_journal_page_last               9057
_journal_paper_doi               10.1021/ja800964g
_journal_volume                  130
_journal_year                    2008
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C9 H10 F2 N2 O4'
_chemical_formula_sum            'C9 H10 F2 N2 O4'
_chemical_formula_weight         248.19
_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                   6.1711(7)
_cell_length_b                   6.6959(8)
_cell_length_c                   24.683(3)
_cell_measurement_temperature    293(2)
_cell_volume                     1019.9(2)
_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      293(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'SMART 1000 CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0250
_diffrn_reflns_av_sigmaI/netI    0.0220
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            7024
_diffrn_reflns_theta_full        26.39
_diffrn_reflns_theta_max         26.39
_diffrn_reflns_theta_min         1.65
_exptl_absorpt_coefficient_mu    0.150
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.616
_exptl_crystal_description       plate
_exptl_crystal_F_000             512
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.31
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.171
_refine_diff_density_min         -0.141
_refine_diff_density_rms         0.034
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.6(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.022
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     160
_refine_ls_number_reflns         2096
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.022
_refine_ls_R_factor_all          0.0402
_refine_ls_R_factor_gt           0.0352
_refine_ls_shift/su_max          0.027
_refine_ls_shift/su_mean         0.006
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0515P)^2^+0.1904P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0906
_refine_ls_wR_factor_ref         0.0933
_reflns_number_gt                1902
_reflns_number_total             2096
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja800964g-file003.cif
_cod_data_source_block           araFF
_cod_database_code               4108017