A dramatic concentration effect on the stereoselectivity of N-glycosylation for the synthesis of 2'-deoxy-beta-ribonucleosides
Fei Yang; Yugen Zhu; Biao Yu; Chem.Commun. 48 (2012) 7097–; doi:10.1039/c2cc33155a

data_7107963
_publ_section_title
;
 A dramatic concentration effect on the stereoselectivity of
 N-glycosylation for the synthesis of 2'-deoxy-beta-ribonucleosides
;
_journal_name_full               Chem.Commun.
_journal_page_first              7097
_journal_paper_doi               10.1039/c2cc33155a
_journal_volume                  48
_journal_year                    2012
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C26 H22 Cl2 N4 O7'
_chemical_formula_sum            'C26 H22 Cl2 N4 O7'
_chemical_formula_weight         573.38
_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                   8.5141(17)
_cell_length_b                   11.318(2)
_cell_length_c                   26.647(5)
_cell_measurement_reflns_used    4420
_cell_measurement_temperature    295(2)
_cell_measurement_theta_max      66.94
_cell_measurement_theta_min      3.32
_cell_volume                     2567.8(8)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      295(2)
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.975
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0303
_diffrn_reflns_av_sigmaI/netI    0.0425
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            11972
_diffrn_reflns_theta_full        66.94
_diffrn_reflns_theta_max         66.94
_diffrn_reflns_theta_min         3.32
_exptl_absorpt_coefficient_mu    2.750
_exptl_absorpt_correction_T_max  0.803
_exptl_absorpt_correction_T_min  0.7070
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.483
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       column
_exptl_crystal_F_000             1184
_exptl_crystal_size_max          0.23
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.143
_refine_diff_density_min         -0.224
_refine_diff_density_rms         0.041
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.024(15)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.075
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     352
_refine_ls_number_reflns         4396
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.075
_refine_ls_R_factor_all          0.0431
_refine_ls_R_factor_gt           0.0380
_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^)+(0.0504P)^2^+0.1772P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0968
_refine_ls_wR_factor_ref         0.1007
_reflns_number_gt                3953
_reflns_number_total             4396
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c2cc33155a.txt
_cod_data_source_block           362
_cod_original_cell_volume        2567.7(9)
_cod_database_code               7107963