Biomimetic synthesis of the tetracyclic core of berkelic acid.
Zhou, Jingye; Snider, Barry B.; Organic letters 9 (2007) 2071–2074; doi:10.1021/ol0704338

data_1505366
_publ_section_title
;
 Biomimetic synthesis of the tetracyclic core of berkelic acid.
;
_journal_issue                   11
_journal_name_full               'Organic letters'
_journal_page_first              2071
_journal_page_last               2074
_journal_paper_doi               10.1021/ol0704338
_journal_volume                  9
_journal_year                    2007
_chemical_formula_moiety         'C21 H28 O6'
_chemical_formula_sum            'C21 H28 O6'
_chemical_formula_weight         376.45
_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
_audit_creation_date             07-01-26
_audit_creation_method           CRYSTALS_ver_12.84
_cell_angle_alpha                90
_cell_angle_beta                 117.621(4)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   20.844(3)
_cell_length_b                   5.1846(7)
_cell_length_c                   19.858(3)
_cell_measurement_reflns_used    3068
_cell_measurement_temperature    120
_cell_measurement_theta_max      25
_cell_measurement_theta_min      2
_cell_volume                     1901.4(5)
_computing_cell_refinement       'SAINT (Siemens ,1995)'
_computing_data_collection       'SMART (Siemens, 1993)'
_computing_data_reduction        'SAINT (Siemens ,1995)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'SIR92 (Altomare et al., 1994)'
_diffrn_ambient_temperature      120
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.944
_diffrn_measurement_device_type  'Bruker KappaCCD ApexII'
_diffrn_measurement_method       '\f & \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.041
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       -23
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -23
_diffrn_reflns_number            10978
_diffrn_reflns_theta_full        18.709
_diffrn_reflns_theta_max         24.946
_diffrn_reflns_theta_min         1.103
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.095
_exptl_absorpt_correction_T_max  0.98
_exptl_absorpt_correction_T_min  0.96
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'DENZO/SCALEPACK (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.315
_exptl_crystal_description       prism
_exptl_crystal_F_000             808
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.48
_exptl_crystal_size_min          0.24
_refine_diff_density_max         0.45
_refine_diff_density_min         -0.37
_refine_ls_extinction_method     None
_refine_ls_goodness_of_fit_ref   0.9088
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     356
_refine_ls_number_reflns         3140
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0763
_refine_ls_R_factor_gt           0.0513
_refine_ls_shift/su_max          0.000912
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 Method= Modified Sheldrick 
 w=1/[\s^2^(F^2^) + ( 0.09P)^2^ + 0.00P] 
 ,where P=(max(Fo^2^,0) + 2Fc^2^)/3 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1447
_refine_ls_wR_factor_gt          0.1304
_refine_ls_wR_factor_ref         0.1447
_reflns_limit_h_max              20
_reflns_limit_h_min              -24
_reflns_limit_k_max              6
_reflns_limit_k_min              0
_reflns_limit_l_max              23
_reflns_limit_l_min              0
_reflns_number_gt                2111
_reflns_number_total             3140
_reflns_threshold_expression     I>2.0\s(I)
_oxford_diffrn_Wilson_B_factor   2.57
_oxford_diffrn_Wilson_scale      3.19
_oxford_refine_ls_scale          0.563(2)
_oxford_structure_analysis_title 'ziy_8_149_1_0ma in P2(1)/c'
_cod_data_source_file            ol0704338si20070220_051437.cif
_cod_data_source_block           ziy_8_149_1_cif
_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_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        1901.5(4)
_cod_original_sg_symbol_H-M      'P 1 21/c 1 '
_cod_database_code               1505366