Total Synthesis of (-)-Batrachotoxinin A: A Local-Desymmetrization Approach.
Guo, Yinliang; Guo, Zhixian; Lu, Jia-Tian; Fang, Runting; Chen, Si-Cong; Luo, Tuoping; Journal of the American Chemical Society 142 (2020) 3675–3679; doi:10.1021/jacs.9b12882

data_4134186
_publ_section_title
;
 Total Synthesis of (-)-Batrachotoxinin A: A Local-Desymmetrization
 Approach.
;
_journal_issue                   8
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              3675
_journal_page_last               3679
_journal_paper_doi               10.1021/jacs.9b12882
_journal_volume                  142
_journal_year                    2020
_chemical_absolute_configuration ad
_chemical_formula_sum            'C25 H36 O6 Si'
_chemical_formula_weight         460.63
_space_group_crystal_system      tetragonal
_space_group_IT_number           96
_space_group_name_Hall           'P 4nw 2abw'
_space_group_name_H-M_alt        'P 43 21 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   10.85610(10)
_cell_length_b                   10.85610(10)
_cell_length_c                   41.1767(6)
_cell_measurement_reflns_used    29051
_cell_measurement_temperature    179.99(10)
_cell_measurement_theta_max      29.2860
_cell_measurement_theta_min      2.0180
_cell_volume                     4852.88(9)
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      179.99(10)
_diffrn_detector                 'CCD plate'
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB AFC12 (RINC): Kappa single'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0454
_diffrn_reflns_av_unetI/netI     0.0208
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       53
_diffrn_reflns_limit_l_min       -53
_diffrn_reflns_number            64432
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.485
_diffrn_reflns_theta_min         1.940
_diffrn_source                   'fine-focus sealed X-ray tube'
_diffrn_source_type              'Enhance (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    0.134
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.48464
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.39.29a (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.261
_exptl_crystal_description       rod-like
_exptl_crystal_F_000             1984
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.231
_refine_diff_density_min         -0.206
_refine_diff_density_rms         0.045
_refine_ls_abs_structure_details
;
 Flack x determined using 2049 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.02(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.017
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     295
_refine_ls_number_reflns         5565
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.017
_refine_ls_R_factor_all          0.0359
_refine_ls_R_factor_gt           0.0334
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0540P)^2^+0.9455P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0873
_refine_ls_wR_factor_ref         0.0888
_reflns_Friedel_coverage         0.685
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                5266
_reflns_number_total             5565
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja9b12882_si_007.cif
_cod_data_source_block           3
_cod_depositor_comments
'Adding full bibliography for 4134185--4134193.cif.'
_cod_original_cell_volume        4852.88(11)
_cod_database_code               4134186
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              76455
_shelx_hkl_checksum              4612