Selectivity in the cycloadditions of carbonyl ylides with glyoxylates: an approach to the zaragozic acids—squalestatins
Hodgson, David M.; Bailey, James M.; Villalonga-Barber, Carolina; Drew, Michael G. B.; Harrison, Timothy; Journal of the Chemical Society, Perkin Transactions 1  (2000) 3432–; doi:10.1039/b004870o

data_7213401
_publ_section_title
;
 Selectivity in the cycloadditions of carbonyl ylides with glyoxylates: an
 approach to the zaragozic acids---squalestatins
;
_journal_issue                   20
_journal_name_full
'Journal of the Chemical Society, Perkin Transactions 1'
_journal_page_first              3432
_journal_paper_doi               10.1039/b004870o
_journal_year                    2000
_chemical_formula_sum            'C12 H16 O7'
_chemical_formula_weight         272.24
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                69.549(10)
_cell_angle_beta                 76.797(10)
_cell_angle_gamma                71.600(10)
_cell_formula_units_Z            2
_cell_length_a                   8.405(9)
_cell_length_b                   9.044(9)
_cell_length_c                   10.192(12)
_cell_measurement_reflns_used    all
_cell_measurement_temperature    293(2)
_cell_volume                     682.7(13)
_computing_cell_refinement       XDS
_computing_data_collection       'XDS (Kabsch, 1991)'
_computing_data_reduction        XDS
_computing_molecular_graphics    PLATON(Spek,1994)
_computing_structure_refinement  'SHELXL-93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'Marresearch Image Plate'
_diffrn_measurement_method
'95 frames at 2^o intervals, counting time 2 min.'
_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  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0257
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            1863
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         2.76
_diffrn_standards_number         all
_exptl_absorpt_coefficient_mu    0.110
_exptl_absorpt_correction_type   none
_exptl_crystal_density_diffrn    1.324
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             288
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.25
_refine_diff_density_max         0.214
_refine_diff_density_min         -0.252
_refine_diff_density_rms         0.068
_refine_ls_extinction_coef       0.82(9)
_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   0.291
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     177
_refine_ls_number_reflns         1863
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.291
_refine_ls_R_factor_all          0.0722
_refine_ls_R_factor_gt           0.0645
_refine_ls_shift/su_max          0.028
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.5242P)^2^+2.9340P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1822
_refine_ls_wR_factor_ref         0.2011
_reflns_number_gt                1595
_reflns_number_total             1863
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b004870osup1.cif
_cod_data_source_block           1
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.5242P)^2^+2.9340P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.5242P)^2^+2.9340P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      P-1
_cod_original_formula_sum        'C12 H16 O7    '
_cod_database_code               7213401