Total synthesis of (+/-)-aspercyclide A and its C19 methyl ether.
Carr, James L; Offermann, Daniel A; Holdom, Mary D; Dusart, Philip; White, Andrew J P; Beavil, Andrew J; Leatherbarrow, Robin J; Lindell, Stephen D; Sutton, Brian J; Spivey, Alan C; Chemical communications (Cambridge, England) 46 (2010) 1824–1826; doi:10.1039/b923528k

data_7105296
_publ_section_title
;
 Total synthesis of (+/-)-aspercyclide A and its C19 methyl ether.
;
_journal_issue                   11
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              1824
_journal_page_last               1826
_journal_paper_doi               10.1039/b923528k
_journal_volume                  46
_journal_year                    2010
_chemical_formula_moiety         'C25 H28 O6'
_chemical_formula_sum            'C25 H28 O6'
_chemical_formula_weight         424.47
_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
_cell_angle_beta                 93.1039(14)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   18.7407(3)
_cell_length_b                   8.56319(13)
_cell_length_c                   13.73354(18)
_cell_measurement_reflns_used    4220
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      71.0802
_cell_measurement_theta_min      2.3576
_cell_volume                     2200.73(6)
_computing_cell_refinement       'CrysAlis RED, Oxford Diffraction Ltd'
_computing_data_collection       'CrysAlis CCD, Oxford Diffraction Ltd'
_computing_data_reduction        'CrysAlis RED, Oxford Diffraction Ltd'
_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      173(2)
_diffrn_detector_area_resol_mean 8.2556
_diffrn_measured_fraction_theta_full 0.985
_diffrn_measured_fraction_theta_max 0.981
_diffrn_measurement_device_type  'OD Xcalibur PX Ultra'
_diffrn_measurement_method       'omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance Ultra (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0202
_diffrn_reflns_av_sigmaI/netI    0.0232
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            9522
_diffrn_reflns_theta_full        71.00
_diffrn_reflns_theta_max         71.27
_diffrn_reflns_theta_min         2.36
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.743
_exptl_absorpt_correction_T_max  0.965
_exptl_absorpt_correction_T_min  0.812
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details
;
CrysAlis RED, Oxford Diffraction Ltd.,
Version 1.171.33.31 (release 08-01-2009 CrysAlis171 .NET)
(compiled Jan 8 2009,16:24:04)
Analytical numeric absorption correction using a multifaceted crystal
model based on expressions derived by R.C. Clark & J.S. Reid.
(Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)
;
_exptl_crystal_colour            Colourless
_exptl_crystal_density_diffrn    1.281
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'canoe-shaped plates'
_exptl_crystal_F_000             904
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.29
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.196
_refine_diff_density_min         -0.205
_refine_diff_density_rms         0.039
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.041
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     285
_refine_ls_number_reflns         4188
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.041
_refine_ls_R_factor_all          0.0625
_refine_ls_R_factor_gt           0.0429
_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^)+(0.0650P)^2^+0.3389P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1126
_refine_ls_wR_factor_ref         0.1214
_reflns_number_gt                3114
_reflns_number_total             4188
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b923528k.txt
_cod_data_source_block           15a
_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_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7105296