1,10-Dehydrosalviarin
Mattia, Carlo Andrea; De Feo, Vincenzo; Quaranta, Emilia; Bisio, Angela; Romussi, Giovanni; Puliti, Raffaella; Acta Crystallographica Section E 62 (2006) o559–o562; doi:10.1107/S160053680600050X

data_2208127
_publ_section_title
;
 1,10-Dehydrosalviarin
;
_journal_coeditor_code           NC2001
_journal_issue                   2
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o559
_journal_page_last               o562
_journal_paper_doi               10.1107/S160053680600050X
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C20 H20 O5'
_chemical_formula_moiety         'C20 H20 O5'
_chemical_formula_sum            'C20 H20 O5'
_chemical_formula_weight         340.36
_chemical_name_common            1,10-dehydrosalviarin
_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
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.014(7)
_cell_length_b                   11.970(12)
_cell_length_c                   17.239(18)
_cell_measurement_reflns_used    5071
_cell_measurement_temperature    291(2)
_cell_measurement_theta_max      20.60
_cell_measurement_theta_min      4.59
_cell_volume                     1654(3)
_computing_cell_refinement       'DIRAX (Duisenberg, 1992)'
_computing_data_collection       'COLLECT (Hooft, 1999)'
_computing_data_reduction        COLLECT
_computing_molecular_graphics    'ORTEP-3 (Farrugia, 1997)'
_computing_publication_material  SHELXL97
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SIR97 (Altomare <i>et al.</i>,  1999)'
_diffrn_ambient_temperature      291(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.978
_diffrn_measured_fraction_theta_max 0.978
_diffrn_measurement_device       '95 mm CCD camera on \k-goniostat'
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\f and \w'
_diffrn_radiation_monochromator  'horizonally mounted graphite crystal'
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0357
_diffrn_reflns_av_sigmaI/netI    0.0434
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            12254
_diffrn_reflns_theta_full        27.55
_diffrn_reflns_theta_max         27.55
_diffrn_reflns_theta_min         4.15
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.098
_exptl_absorpt_correction_T_max  0.9855
_exptl_absorpt_correction_T_min  0.9032
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2003)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.367
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'elongated prism'
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.134
_refine_diff_density_min         -0.168
_refine_ls_abs_structure_details
;
Flack test results are meaningless (Flack, 1983), therefore the
absolute configuration was chosen according to that of the known
clerodin bromalactone (Rogers <i>et al.</i>,  1979)
;
_refine_ls_abs_structure_Flack   -1.4(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.003
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     227
_refine_ls_number_reflns         2149
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.003
_refine_ls_R_factor_all          0.0658
_refine_ls_R_factor_gt           0.0354
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0402P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0658
_refine_ls_wR_factor_ref         0.0733
_reflns_number_gt                1517
_reflns_number_total             2149
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            nc2001.cif
_cod_data_source_block           I
_cod_database_code               2208127