Total Synthesis and Structural Determination of the Dimeric Tetrahydroxanthone Ascherxanthone A.
Xiao, Zheming; Li, Yayue; Gao, Shuanhu; Organic letters 19 (2017) 1834–1837; doi:10.1021/acs.orglett.7b00592

data_1545661
_publ_section_title
;
 Total Synthesis and Structural Determination of the Dimeric
 Tetrahydroxanthone Ascherxanthone A.
;
_journal_issue                   7
_journal_name_full               'Organic letters'
_journal_page_first              1834
_journal_page_last               1837
_journal_paper_doi               10.1021/acs.orglett.7b00592
_journal_volume                  19
_journal_year                    2017
_chemical_formula_sum            'C18 H26 O5'
_chemical_formula_weight         322.39
_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
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 104.1300(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   13.7608(4)
_cell_length_b                   7.3158(2)
_cell_length_c                   17.9639(5)
_cell_measurement_reflns_used    6567
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      26.26
_cell_measurement_theta_min      2.46
_cell_volume                     1753.73(9)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker Smart Apex II CCD'
_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  0.0260
_diffrn_reflns_av_sigmaI/netI    0.0178
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -16
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            19838
_diffrn_reflns_theta_full        25.01
_diffrn_reflns_theta_max         25.01
_diffrn_reflns_theta_min         1.53
_exptl_absorpt_coefficient_mu    0.088
_exptl_absorpt_correction_T_max  0.9792
_exptl_absorpt_correction_T_min  0.9665
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.221
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             696
_exptl_crystal_size_max          0.39
_exptl_crystal_size_mid          0.33
_exptl_crystal_size_min          0.24
_refine_diff_density_max         0.364
_refine_diff_density_min         -0.227
_refine_diff_density_rms         0.033
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     208
_refine_ls_number_reflns         3098
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.0556
_refine_ls_R_factor_gt           0.0442
_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^)+(0.0684P)^2^+0.5744P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1249
_refine_ls_wR_factor_ref         0.1358
_reflns_number_gt                2490
_reflns_number_total             3098
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol7b00592_si_003.cif
_cod_data_source_block           z
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/home/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4973 2017-02-22 13:04:09Z antanas 

 Adding full bibliography for 1545661--1545663.cif.
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               1545661