Xanthyletin
Rudiño-Piñera, E.; Juárez-Martínez, G.; Panneerselvam, K.; Soriano-García, M.; Anaya, A. L.; García-Santana, C.; Mata, R.; Sánchez, P.; Acta Crystallographica Section C 51 (1995) 2720–2722; doi:10.1107/S0108270195009309

data_2004271
_publ_section_title
;
 Xanthyletin
;
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              2720
_journal_page_last               2722
_journal_paper_doi               10.1107/S0108270195009309
_journal_volume                  51
_journal_year                    1995
_chemical_formula_moiety         'C14 H12 O3'
_chemical_formula_sum            'C14 H12 O3'
_chemical_formula_weight         228.24
_chemical_melting_point          .13E-128
_chemical_name_common            xanthyletin
_chemical_name_systematic
;
8,8-dimethyl-2H,8H-benzo[1,2-b:5,4-b']dipyran-2-one
;
_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'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 104.25(1)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.830(1)
_cell_length_b                   11.658(2)
_cell_length_c                   11.492(2)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      30
_cell_measurement_theta_min      15
_cell_volume                     1146.6(3)
_computing_cell_refinement       'XSCANS (Siemens, 1992)'
_computing_data_collection       'P4 diffractometer software'
_computing_data_reduction        'XSCANS (Siemens, 1992)'
_computing_molecular_graphics    'SHELXTL-Plus (Sheldrick, 1990)'
_computing_publication_material  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_refinement  'SHELXL93 (Sheldrick, 1993)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1985)'
_diffrn_ambient_temperature      293(2)
_diffrn_measurement_device       'Siemens P4'
_diffrn_measurement_method       \q/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0231
_diffrn_reflns_av_sigmaI/netI    0.0188
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -1
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -1
_diffrn_reflns_number            2083
_diffrn_reflns_theta_max         56.61
_diffrn_reflns_theta_min         3.00
_diffrn_standards_decay_%        3
_diffrn_standards_interval_count 100
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.760
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.322
_exptl_crystal_description       trigonal
_exptl_crystal_F_000             480
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.137
_refine_diff_density_min         -0.202
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_all   1.129
_refine_ls_goodness_of_fit_obs   1.172
_refine_ls_hydrogen_treatment    'All H atoms were refined isotropically'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     202
_refine_ls_number_reflns         1313
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.129
_refine_ls_restrained_S_obs      1.172
_refine_ls_R_factor_all          0.0501
_refine_ls_R_factor_obs          0.0440
_refine_ls_shift/esd_max         0.023
_refine_ls_shift/esd_mean        0.004
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_scheme
;
calc w = 1/[\s^2^(F~o~^2^) + (0.0782P)^2^ + 0.1280P]
where P = (F~o~^2^ + 2F~c~^2^)/3
;
_refine_ls_wR_factor_all         0.1259
_refine_ls_wR_factor_obs         0.1199
_reflns_number_observed          1313
_reflns_number_total             1524
_reflns_observed_criterion       >2sigma(I)
_cod_data_source_file            ka1139.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2004271