Synthetic studies on cyathins: enantioselective total synthesis of (+)-allocyathin B2.
Takano, Masashi; Umino, Akinori; Nakada, Masahisa; Organic letters 6 (2004) 4897–4900; doi:10.1021/ol048010i

data_1506929
_publ_section_title
;
 Synthetic studies on cyathins: enantioselective total synthesis of
 (+)-allocyathin B2.
;
_journal_issue                   26
_journal_name_full               'Organic letters'
_journal_page_first              4897
_journal_page_last               4900
_journal_paper_doi               10.1021/ol048010i
_journal_volume                  6
_journal_year                    2004
_chemical_absolute_configuration 'CHOOSE rm ad rmad syn or unk'
_chemical_formula_moiety         'C23 H32 O4 '
_chemical_formula_sum            'C23 H32 O4'
_chemical_formula_weight         372.50
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.729(8)
_cell_length_b                   11.35(1)
_cell_length_c                   20.09(2)
_cell_measurement_reflns_used    18142
_cell_measurement_temperature    93.1
_cell_measurement_theta_max      27.5
_cell_measurement_theta_min      3.0
_cell_volume                     1990(3)
_computing_cell_refinement       PROCESS-AUTO
_computing_data_collection       PROCESS-AUTO
_computing_data_reduction        CrystalStructure
_computing_publication_material  'CrystalStructure 3.6.0'
_computing_structure_refinement  CRYSTALS
_computing_structure_solution    SIR92
_diffrn_detector_area_resol_mean 10.00
_diffrn_measured_fraction_theta_full 0.9939
_diffrn_measured_fraction_theta_max 0.9939
_diffrn_measurement_device_type  'Rigaku RAXIS-RAPID'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.7107
_diffrn_reflns_av_R_equivalents  0.023
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            19168
_diffrn_reflns_theta_full        27.48
_diffrn_reflns_theta_max         27.48
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  0.967
_exptl_absorpt_correction_T_min  0.791
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
    Higashi, T. (1995). Program for Absorption Correction.
    Rigaku Corporation, Tokyo, Japan.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.243
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             808.00
_exptl_crystal_size_max          1.40
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.40
_refine_diff_density_max         0.42
_refine_diff_density_min         -0.42
_refine_ls_abs_structure_details
'Flack, H. D. (1983), Acta Cryst. A39, 876-881.  1928 Friedel Pairs'
_refine_ls_abs_structure_Flack   0.4(8)
_refine_ls_extinction_coef       -148(28)
_refine_ls_extinction_method
'Larson (1970) Crystallographic Computing eq. 22'
_refine_ls_goodness_of_fit_ref   0.954
_refine_ls_hydrogen_treatment    refall
_refine_ls_number_parameters     534
_refine_ls_number_reflns         3766
_refine_ls_R_factor_gt           0.0320
_refine_ls_shift/su_max          0.0040
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[0.0010Fo^2^ + 1.0000\s(Fo^2^)]/(4Fo^2^)'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         0.0820
_reflns_number_gt                3766
_reflns_number_total             4545
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            ol048010isi20040929_104945.cif
_cod_data_source_block           '_nmt04'
_cod_original_formula_sum        'C23 H32 O4 '
_cod_database_code               1506929