Cytotoxic alkaloids from the twigs and leaves of <i>Cephalotaxus sinensis</i>.
Zhang, Fuxin; Yang, Tao; Yang, Kailing; Zhou, Ruixi; Zhang, Yu; Chen, Wenwen; Liu, Zhetong; Zhan, Guanqun; Guo, Zengjun; Organic & biomolecular chemistry 21 (2022) 169–178; doi:10.1039/d2ob01980a

data_7159018
_publ_section_title
;
 Cytotoxic alkaloids from the twigs and leaves of <i>Cephalotaxus
 sinensis</i>.
;
_journal_issue                   1
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              169
_journal_page_last               178
_journal_paper_doi               10.1039/d2ob01980a
_journal_volume                  21
_journal_year                    2022
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C18 H21 N O4'
_chemical_formula_sum            'C18 H21 N O4'
_chemical_formula_weight         315.36
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2021-11-24
_audit_creation_method
; 
Olex2 1.3 
(compiled 2020.11.12 svn.r5f609507 for OlexSys, GUI svn.r6408) 
;
_audit_update_record
;
2022-10-19 deposited with the CCDC.	2022-11-28 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.3100(17)
_cell_length_b                   10.917(2)
_cell_length_c                   17.120(4)
_cell_measurement_reflns_used    8473
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      72.36
_cell_measurement_theta_min      3.52
_cell_volume                     1553.1(6)
_computing_cell_refinement       'SAINT V8.40B (?, 2016)'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'SAINT V8.40B (?, 2016)'
_computing_molecular_graphics    'Olex2 1.3 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.3 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL  (Sheldrick, 2008)'
_computing_structure_solution    'XM  (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.982
_diffrn_measured_fraction_theta_max 0.988
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           GaK\a
_diffrn_radiation_wavelength     1.34139
_diffrn_reflns_av_R_equivalents  0.0733
_diffrn_reflns_av_unetI/netI     0.0455
_diffrn_reflns_Laue_measured_fraction_full 0.982
_diffrn_reflns_Laue_measured_fraction_max 0.988
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            32663
_diffrn_reflns_point_group_measured_fraction_full 0.984
_diffrn_reflns_point_group_measured_fraction_max 0.989
_diffrn_reflns_theta_full        53.594
_diffrn_reflns_theta_max         72.482
_diffrn_reflns_theta_min         4.494
_diffrn_source_current           3.57
_diffrn_source_power             0.2497215
_diffrn_source_voltage           69.95
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.495
_exptl_absorpt_correction_T_max  0.7536
_exptl_absorpt_correction_T_min  0.6072
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS-2016/2 (Bruker,2016/2)'
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.349
_exptl_crystal_description       block
_exptl_crystal_F_000             672
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.332
_refine_diff_density_min         -0.270
_refine_diff_density_rms         0.067
_refine_ls_abs_structure_details
; 
 Flack x determined using 1979 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   0.11(5)
_refine_ls_extinction_coef       0.041(5)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2018/3 (Sheldrick 2018)'
_refine_ls_goodness_of_fit_ref   1.079
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     212
_refine_ls_number_reflns         4627
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.079
_refine_ls_R_factor_all          0.0353
_refine_ls_R_factor_gt           0.0352
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0580P)^2^+0.1568P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0947
_refine_ls_wR_factor_ref         0.0948
_reflns_Friedel_coverage         0.761
_reflns_Friedel_fraction_full    0.988
_reflns_Friedel_fraction_max     0.990
_reflns_number_gt                4606
_reflns_number_total             4627
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d2ob01980a2.cif
_cod_data_source_block           211123j_0m
_cod_depositor_comments
'Adding full bibliography for 7159015--7159021.cif.'
_cod_original_cell_volume        1553.1(5)
_cod_database_code               7159018
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_max   0.943
_shelx_estimated_absorpt_t_min   0.866
_olex2_refinement_description
; 
1. Fixed Uiso 
 At 1.2 times of: 
  All C(H) groups, All C(H,H) groups 
 At 1.5 times of: 
  All C(H,H,H) groups, All O(H) groups 
2.a Ternary CH refined with riding coordinates: 
 C3(H3), C4(H4), C11(H11) 
2.b Secondary CH2 refined with riding coordinates: 
 C6(H6A,H6B), C7(H7A,H7B), C8(H8A,H8B), C10(H10A,H10B) 
2.c Aromatic/amide H refined with riding coordinates: 
 C1(H1), C14(H14), C17(H17) 
2.d Idealised Me refined as rotating group: 
 C9(H9A,H9B,H9C), C18(H18A,H18B,H18C) 
2.e Idealised tetrahedral OH refined as rotating group: 
 O3(H3A) 
;
_olex2_submission_special_instructions 'No special instructions were received'