Explorations into Neolignan Biosynthesis: Concise Total Syntheses of Helicterin B, Helisorin, and Helisterculin A from a Common Intermediate
Scott A. Snyder; Ferenc Kontes; Journal of the American Chemical Society 131 (2009) 1745–1752; doi:10.1021/ja806865u

data_4103870
_publ_section_title
;
 Explorations into Neolignan Biosynthesis: Concise Total Syntheses of
 Helicterin B, Helisorin, and Helisterculin A from a Common Intermediate
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              1745
_journal_page_last               1752
_journal_paper_doi               10.1021/ja806865u
_journal_volume                  131
_journal_year                    2009
_chemical_formula_sum            'C22 H25 O8'
_chemical_formula_weight         417.42
_chemical_name_systematic
;
 ?
;
_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                70.152(4)
_cell_angle_beta                 81.717(4)
_cell_angle_gamma                81.656(4)
_cell_formula_units_Z            2
_cell_length_a                   8.224(2)
_cell_length_b                   10.543(3)
_cell_length_c                   12.410(3)
_cell_measurement_reflns_used    2455
_cell_measurement_temperature    125(2)
_cell_measurement_theta_max      30.37
_cell_measurement_theta_min      2.52
_cell_volume                     996.2(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      125(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_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  0.0987
_diffrn_reflns_av_sigmaI/netI    0.1586
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            15972
_diffrn_reflns_theta_full        30.58
_diffrn_reflns_theta_max         30.58
_diffrn_reflns_theta_min         1.75
_exptl_absorpt_coefficient_mu    0.106
_exptl_absorpt_correction_T_max  0.9947
_exptl_absorpt_correction_T_min  0.9843
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.392
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             442
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.550
_refine_diff_density_min         -0.688
_refine_diff_density_rms         0.070
_refine_ls_extinction_coef       0.0042(16)
_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   1.010
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     272
_refine_ls_number_reflns         6069
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.010
_refine_ls_R_factor_all          0.1891
_refine_ls_R_factor_gt           0.0641
_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^)+(0.0500P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1234
_refine_ls_wR_factor_ref         0.1585
_reflns_number_gt                2470
_reflns_number_total             6069
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja806865u_si_006.cif
_cod_data_source_block           ky80as10
_cod_depositor_comments
;
The following automatic conversions were performed:

'_refine_ls_hydrogen_treatment' value 'CONSTR' changed to 'constr'
according to the built-in table from CIF Core 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_database_code               4103870