Unusual immunosuppressive pyridine-containing <i>bisnor</i>- (c<sub>23</sub>), <i>tetranor</i>- (c<sub>21</sub>) and <i>pentanor</i>- (c<sub>20</sub>) sesterterpenoids from Tibetan <i>Leucosceptrum canum</i>.
Li, Man; Feng, Ling; Zhang, Han; Liu, Yan-Chun; Zhou, Ting-Ting; Zheng, Yu; Guo, Kai; Liu, Yan; Li, Sheng-Hong; Organic & biomolecular chemistry 22 (2024) 3019–3024; doi:10.1039/d4ob00334a

data_7159857
_publ_section_title
;
 Unusual immunosuppressive pyridine-containing <i>bisnor</i>-
 (c<sub>23</sub>), <i>tetranor</i>- (c<sub>21</sub>) and <i>pentanor</i>-
 (c<sub>20</sub>) sesterterpenoids from Tibetan <i>Leucosceptrum
 canum</i>.
;
_journal_issue                   15
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3019
_journal_page_last               3024
_journal_paper_doi               10.1039/d4ob00334a
_journal_volume                  22
_journal_year                    2024
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C20 H30 O5, 0.5(C3 H6 O)'
_chemical_formula_sum            'C21.5 H33 O5.5'
_chemical_formula_weight         379.47
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2024-01-18 deposited with the CCDC.	2024-03-21 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 108.1710(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.1840(5)
_cell_length_b                   14.8969(7)
_cell_length_c                   14.1070(7)
_cell_measurement_reflns_used    9896
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      70.32
_cell_measurement_theta_min      4.57
_cell_volume                     2033.44(17)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014 (Sheldrick 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.976
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0482
_diffrn_reflns_av_unetI/netI     0.0503
_diffrn_reflns_Laue_measured_fraction_full 0.991
_diffrn_reflns_Laue_measured_fraction_max 0.976
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            19231
_diffrn_reflns_point_group_measured_fraction_full 0.843
_diffrn_reflns_point_group_measured_fraction_max 0.823
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         70.314
_diffrn_reflns_theta_min         3.297
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.713
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.240
_exptl_crystal_description       block
_exptl_crystal_F_000             824
_exptl_crystal_size_max          0.900
_exptl_crystal_size_mid          0.800
_exptl_crystal_size_min          0.300
_exptl_transmission_factor_max   0.7533
_exptl_transmission_factor_min   0.4349
_refine_diff_density_max         0.405
_refine_diff_density_min         -0.409
_refine_diff_density_rms         0.086
_refine_ls_abs_structure_details
;
 Flack x determined using 2340 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.03(7)
_refine_ls_extinction_coef       0.0076(10)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   1.054
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     504
_refine_ls_number_reflns         6390
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.053
_refine_ls_R_factor_all          0.0539
_refine_ls_R_factor_gt           0.0536
_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^)+(0.1121P)^2^+0.4084P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1405
_refine_ls_wR_factor_ref         0.1408
_reflns_Friedel_coverage         0.620
_reflns_Friedel_fraction_full    0.682
_reflns_Friedel_fraction_max     0.657
_reflns_number_gt                6337
_reflns_number_total             6390
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4ob00334a2.cif
_cod_data_source_block           cu_glt27_0m
_cod_depositor_comments
;
          Adding full bibliography for 7159857.cif.

2024-12-16
Z value and formula fixed to values more according to usual
chemical conventions.                 miguel
;
_cod_original_formula_sum            'C43 H66 O11'
_cod_original_formula_weight         758.95
_cod_original_formula_moiety         '2(C20 H30 O5), C3 H6 O'
_cod_original_formula_units_Z            2
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               7159857
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.566
_shelx_estimated_absorpt_t_max   0.814
_shelx_res_checksum              54684