Two Pairs of Stereoisomers of Dimethyl 2-(3,4,5-Trimethoxyphenyl)tetrahydrofuran-3,4-dicarboxylate
Yang, Qing-chuan; Song, Yi-qiu; Tang, You-qi; Pei, Wei-wei; Li, Shao-hu; Ye, Xiu-lin; Acta Crystallographica Section C 53 (1997) 1133–1136; doi:10.1107/S0108270197004447

data_2006373
_publ_section_title
;
 Two Pairs of Stereoisomers of Dimethyl
 2-(3,4,5-Trimethoxyphenyl)tetrahydrofuran-3,4-dicarboxylate
;
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1133
_journal_page_last               1136
_journal_paper_doi               10.1107/S0108270197004447
_journal_volume                  53
_journal_year                    1997
_chemical_formula_sum            'C17 H22 O8'
_chemical_formula_weight         354.35
_chemical_melting_point          369.6(5)
_chemical_name_systematic
;
 (2S,3R,4S) and  (2R,3S,4S) -dimethyl-2-(3,4,5-trimethoxyphenyl)
 tetrahydrofuran-3,4-dicarboxylate ((Ib))
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 96.57(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.385(2)
_cell_length_b                   19.521(7)
_cell_length_c                   16.700(8)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      10.12
_cell_measurement_theta_min      4.29
_cell_volume                     1744.0(12)
_computing_cell_refinement       'MSC/AFC Diffractometer Control Software'
_computing_data_collection
;
MSC/AFC Diffractometer Control Software (Molecular Structure Corporation,
1994)
;
_computing_data_reduction
'TEXSAN (Molecular Structure Corporation, 1985)'
_computing_molecular_graphics    SHELXTL-Plus
_computing_publication_material  SHELXTL-Plus
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXTL-Plus (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'Rigaku AFC6S'
_diffrn_measurement_method       \q/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0306
_diffrn_reflns_av_sigmaI/netI    0.0789
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       23
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            3416
_diffrn_reflns_theta_max         25
_diffrn_reflns_theta_min         2.09
_diffrn_standards_decay_%        1.0
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.108
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.350
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             752
_exptl_crystal_size_max          0.80
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.251
_refine_diff_density_min         -0.171
_refine_ls_extinction_coef       0.024(3)
_refine_ls_extinction_method     SHELXL93
_refine_ls_goodness_of_fit_all   0.960
_refine_ls_goodness_of_fit_obs   1.065
_refine_ls_hydrogen_treatment    'H atoms riding with fixed isotropic U'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     227
_refine_ls_number_reflns         3019
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.235
_refine_ls_restrained_S_obs      1.065
_refine_ls_R_factor_all          0.1369
_refine_ls_R_factor_obs          .0488
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0784P)^2^+0.0615P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.2023
_refine_ls_wR_factor_obs         .1221
_reflns_number_observed          1561
_reflns_number_total             3077
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            cf1156.cif
_cod_data_source_block           Ib
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
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_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_chemical_melting_point' value '96-97\%' was changed to '369.6(5)' -
it was converted from degrees Celsius(C) to Kelvins(K), the average
value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 1646 2011-03-28 12:23:43Z adriana 

The following automatic conversions were performed:

'_chemical_melting_point' value '96-97\%' was changed to '369.6(5)' -
it was converted from degrees Celsius(C) to Kelvins(K), the average
value was taken and precision was
estimated.

'_symmetry_cell_setting' value 'Monoclinic' changed to
'monoclinic' 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 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0784P)^2^+0.0615P] 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^)+(0.0784P)^2^+0.0615P] 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 21/n'
_cod_database_code               2006373