An efficient method for construction of the angularly fused 6,3,5-tricyclic skeleton of mycorrhizin A and its analogues.
Yu, Binxun; Jiang, Tuo; Quan, Weiguo; Li, Junpeng; Pan, Xinfu; She, Xuegong; Organic letters 11 (2009) 629–632; doi:10.1021/ol8026895

data_1503756
_publ_section_title
;
 An efficient method for construction of the angularly fused
 6,3,5-tricyclic skeleton of mycorrhizin A and its analogues.
;
_journal_issue                   3
_journal_name_full               'Organic letters'
_journal_page_first              629
_journal_page_last               632
_journal_paper_doi               10.1021/ol8026895
_journal_volume                  11
_journal_year                    2009
_chemical_formula_sum            'C12 H16 O4'
_chemical_formula_weight         224.25
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                71.6930(10)
_cell_angle_beta                 87.453(2)
_cell_angle_gamma                78.227(2)
_cell_formula_units_Z            2
_cell_length_a                   7.6126(3)
_cell_length_b                   8.8251(3)
_cell_length_c                   8.9510(4)
_cell_measurement_reflns_used    1706
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      29.44
_cell_measurement_theta_min      2.40
_cell_volume                     558.78(4)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.908
_diffrn_measured_fraction_theta_max 0.908
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0101
_diffrn_reflns_av_sigmaI/netI    0.0212
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            2706
_diffrn_reflns_theta_full        25.50
_diffrn_reflns_theta_max         25.50
_diffrn_reflns_theta_min         2.40
_exptl_absorpt_coefficient_mu    0.099
_exptl_absorpt_correction_T_max  0.9822
_exptl_absorpt_correction_T_min  0.9782
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.333
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             240
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.19
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.223
_refine_diff_density_min         -0.305
_refine_diff_density_rms         0.040
_refine_ls_extinction_coef       0.058(12)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   0.880
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     150
_refine_ls_number_reflns         1890
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.880
_refine_ls_R_factor_all          0.0515
_refine_ls_R_factor_gt           0.0474
_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^)+(0.0875P)^2^+0.4059P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1394
_refine_ls_wR_factor_ref         0.1440
_reflns_number_gt                1656
_reflns_number_total             1890
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol8026895_si_001.cif
_cod_data_source_block           p-
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               1503756