Efficient synthesis of 4-amido-N(5)-acetyl-4-deoxyneuraminic acid and its application to the C-4 modification of sialic acids.
Gao, Zheng-Xi; Wang, Meng; Wang, Shaozhong; Yao, Zhu-Jun; Organic letters 11 (2009) 3678–3681; doi:10.1021/ol901511x

data_1504108
_publ_section_title
;
 Efficient synthesis of 4-amido-N(5)-acetyl-4-deoxyneuraminic acid and its
 application to the C-4 modification of sialic acids.
;
_journal_issue                   16
_journal_name_full               'Organic letters'
_journal_page_first              3678
_journal_page_last               3681
_journal_paper_doi               10.1021/ol901511x
_journal_volume                  11
_journal_year                    2009
_chemical_absolute_configuration ad
_chemical_formula_sum            'C30 H48 N2 O13'
_chemical_formula_weight         644.70
_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                   9.3504(12)
_cell_length_b                   18.666(2)
_cell_length_c                   20.153(3)
_cell_measurement_reflns_used    1379
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30.917
_cell_measurement_theta_min      4.802
_cell_volume                     3517.4(8)
_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  '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
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_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            18741
_diffrn_reflns_theta_full        25.50
_diffrn_reflns_theta_max         25.50
_diffrn_reflns_theta_min         2.02
_exptl_absorpt_coefficient_mu    0.095
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.66402
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.217
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             1384
_exptl_crystal_size_max          0.466
_exptl_crystal_size_mid          0.229
_exptl_crystal_size_min          0.210
_refine_diff_density_max         0.384
_refine_diff_density_min         -0.183
_refine_diff_density_rms         0.048
_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       0.0033(8)
_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   0.812
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     421
_refine_ls_number_reflns         3691
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.812
_refine_ls_R_factor_all          0.1417
_refine_ls_R_factor_gt           0.0640
_refine_ls_shift/su_max          0.047
_refine_ls_shift/su_mean         0.004
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0726P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1432
_refine_ls_wR_factor_ref         0.1651
_reflns_number_gt                1542
_reflns_number_total             3691
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol901511x_si_002.cif
_cod_data_source_block           cd27566
_cod_depositor_comments
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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 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        3517.3(8)
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               1504108