7,8-Dihydroxy-3-methyl-10-oxo-1<i>H</i>,10<i>H</i>-pyrano[4,3-<i>b</i>]chromene-9-carboxylic acid
Wang, Jian-Feng; Zhang, Yong-Jie; Fang, Mei-Juan; Huang, Yao-Jian; Wei, Zan-Bin; Zheng, Zhong-Hui; Su, Wen-Jin; Zhao, Yu-Fen; Acta Crystallographica Section E 59 (2003) o1244–o1245; doi:10.1107/S1600536803016714

data_2202986
_publ_section_title
;7,8-Dihydroxy-3-methyl-10-oxo-1<i>H</i>,10<i>H</i>-pyrano[4,3-<i>b</i>]chromene-9-carboxylic
 acid
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1244
_journal_page_last               o1245
_journal_paper_doi               10.1107/S1600536803016714
_journal_volume                  59
_journal_year                    2003
_chemical_formula_iupac          'C14 H10 O7'
_chemical_formula_moiety         'C14 H10 O7'
_chemical_formula_sum            'C14 H10 O7'
_chemical_formula_weight         290.22
_chemical_melting_point          517.0(10)
_chemical_name_common            'anhydrofulvic acid'
_chemical_name_systematic
;
7,8-Dihydroxy-3-methyl-10-oxo-1H,10H-pyrano[4,3-b]chromene-9-carboxylic acid
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.000(5)
_cell_angle_beta                 90.178(5)
_cell_angle_gamma                90.000(5)
_cell_formula_units_Z            4
_cell_length_a                   7.814(5)
_cell_length_b                   10.085(5)
_cell_length_c                   15.124(5)
_cell_measurement_reflns_used    2225
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      2.4
_cell_volume                     1191.8(10)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'ORTEP-3 (Farrugia, 1997)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR97 (Altomare et al., 1998)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.953
_diffrn_measured_fraction_theta_max 0.953
_diffrn_measurement_device_type  'Bruker AXS area-detector'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0190
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       0
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            2615
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_diffrn_reflns_theta_min         2.43
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 0
_diffrn_standards_interval_time  0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.132
_exptl_absorpt_correction_T_max  0.9869
_exptl_absorpt_correction_T_min  0.9740
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            green
_exptl_crystal_density_diffrn    1.617
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       chunk
_exptl_crystal_F_000             600
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.243
_refine_diff_density_min         -0.202
_refine_ls_extinction_coef       0.013(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   1.092
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     201
_refine_ls_number_reflns         2615
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.092
_refine_ls_R_factor_all          0.0437
_refine_ls_R_factor_gt           0.0368
_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^)+(0.0758P)^2^+0.0975P] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1134
_refine_ls_wR_factor_ref         0.1185
_reflns_number_gt                2225
_reflns_number_total             2615
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ww6101.cif
_cod_data_source_block           I
_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 '516-518' was changed to '517.0(10)'
- 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 '516-518' was changed to '517.0(10)'
- 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.

'_exptl_absorpt_correction_type' value 'Multi-scan'
changed to 'multi-scan' 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      'P 21/c'
_cod_database_code               2202986
_cod_database_fobs_code          2202986