Synthesis of 3',3'-difluoro-2'- hydroxymethyl-4',5'-unsaturated carbocyclic nucleosides.
Yang, Yan-Yan; Xu, Jun; You, Zheng-Wei; Xu, Xiu-Hua; Qiu, Xiao-Long; Qing, Feng-Ling; Organic letters 9 (2007) 5437–5440; doi:10.1021/ol7023955

data_1505642
_publ_section_title
;
 Synthesis of 3',3'-difluoro-2'- hydroxymethyl-4',5'-unsaturated
 carbocyclic nucleosides.
;
_journal_issue                   26
_journal_name_full               'Organic letters'
_journal_page_first              5437
_journal_page_last               5440
_journal_paper_doi               10.1021/ol7023955
_journal_volume                  9
_journal_year                    2007
_chemical_absolute_configuration ad
_chemical_formula_sum            'C28 H19 F2 N3 O12'
_chemical_formula_weight         627.46
_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                   6.8425(9)
_cell_length_b                   15.5174(19)
_cell_length_c                   26.140(3)
_cell_measurement_reflns_used    1942
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      39.574
_cell_measurement_theta_min      5.250
_cell_volume                     2775.5(6)
_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 0.998
_diffrn_measured_fraction_theta_max 0.998
_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  0.1459
_diffrn_reflns_av_sigmaI/netI    0.1012
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       31
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            15864
_diffrn_reflns_theta_full        26.50
_diffrn_reflns_theta_max         26.50
_diffrn_reflns_theta_min         1.53
_exptl_absorpt_coefficient_mu    0.128
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.78935
_exptl_absorpt_correction_type   empirical
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.502
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             1288
_exptl_crystal_size_max          0.489
_exptl_crystal_size_mid          0.101
_exptl_crystal_size_min          0.059
_refine_diff_density_max         0.268
_refine_diff_density_min         -0.298
_refine_diff_density_rms         0.062
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -10(10)
_refine_ls_extinction_coef       0.0074(14)
_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   0.957
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     419
_refine_ls_number_reflns         3282
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.957
_refine_ls_R_factor_all          0.1057
_refine_ls_R_factor_gt           0.0604
_refine_ls_shift/su_max          0.015
_refine_ls_shift/su_mean         0.003
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0607P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1261
_refine_ls_wR_factor_ref         0.1461
_reflns_number_gt                1982
_reflns_number_total             3282
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol7023955-file002.cif
_cod_data_source_block           cd26542
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Orthorhombic' changed to
'orthorhombic' according to
/home/saulius/struct/CIF-dictionaries/cif_core.dic dictionary named
'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1505642