A Unifying Synthesis Approach to the C<sub>18</sub>-, C<sub>19</sub>-, and C<sub>20</sub>-Diterpenoid Alkaloids.
Kou, Kevin G. M.; Kulyk, Svitlana; Marth, Christopher J.; Lee, Jack C.; Doering, Nicolle A.; Li, Beryl X.; Gallego, Gary M.; Lebold, Terry P.; Sarpong, Richmond; Journal of the American Chemical Society 139 (2017) 13882–13896; doi:10.1021/jacs.7b07706

data_4131632
_publ_section_title
;
 A Unifying Synthesis Approach to the C<sub>18</sub>-, C<sub>19</sub>-,
 and C<sub>20</sub>-Diterpenoid Alkaloids.
;
_journal_issue                   39
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              13882
_journal_page_last               13896
_journal_paper_doi               10.1021/jacs.7b07706
_journal_volume                  139
_journal_year                    2017
_chemical_formula_sum            'C22 H29 N O4'
_chemical_formula_weight         371.46
_chemical_name_common            SKI-138C
_chemical_name_systematic
; 
 sarpong86 
;
_space_group.centring_type       primitive
_space_group_crystal_system      orthorhombic
_space_group_IT_number           61
_space_group_name_Hall           '-P 2ac 2ab'
_space_group_name_H-M_alt        'P b c a'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     iterative
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   7.0860(5)
_cell_length_b                   16.5585(10)
_cell_length_c                   32.230(2)
_cell_measurement_reflns_used    9827
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      67.95
_cell_measurement_theta_min      5.34
_cell_volume                     3781.7(4)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    ORTEP-32
_computing_publication_material  WinGX
_computing_structure_refinement  SHELXL-2014
_computing_structure_solution    SHELXT
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.366
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0651
_diffrn_reflns_av_unetI/netI     0.0247
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.994
_diffrn_refln_scan_rate          20
_diffrn_refln_scan_width         2.0
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       37
_diffrn_reflns_limit_l_min       -38
_diffrn_reflns_number            54271
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.994
_diffrn_reflns_theta_full        67.000
_diffrn_reflns_theta_max         68.524
_diffrn_reflns_theta_min         2.742
_diffrn_source                   'microfocus rotating anode'
_exptl_absorpt_coefficient_mu    0.716
_exptl_absorpt_correction_T_max  0.929
_exptl_absorpt_correction_T_min  0.824
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.305
_exptl_crystal_description       plate
_exptl_crystal_F_000             1600
_exptl_crystal_size_max          0.040
_exptl_crystal_size_mid          0.030
_exptl_crystal_size_min          0.010
_refine_diff_density_max         0.476
_refine_diff_density_min         -0.304
_refine_diff_density_rms         0.072
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.032
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     247
_refine_ls_number_reflns         3470
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0937
_refine_ls_R_factor_gt           0.0784
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1129P)^2^+8.5389P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2156
_refine_ls_wR_factor_ref         0.2289
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2771
_reflns_number_total             3470
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja7b07706_si_006.cif
_cod_data_source_block           sarpong86
_cod_database_code               4131632
_shelx_estimated_absorpt_t_min   0.972
_shelx_estimated_absorpt_t_max   0.993
_shelxl_version_number           2014-3
_shelx_res_checksum              76826
_shelx_hkl_checksum              38343