17- nor-Cephalotane-Type Diterpenoids from Cephalotaxus fortunei.
Ge, Zhan-Peng; Liu, Hong-Chun; Wang, Guo-Cai; Liu, Qun-Fang; Xu, Cheng-Hui; Ding, Jian; Fan, Yao-Yue; Yue, Jian-Min; Journal of natural products 82 (2019) 1565–1575; doi:10.1021/acs.jnatprod.9b00059

data_1552663
_publ_section_title
;
 17- nor-Cephalotane-Type Diterpenoids from Cephalotaxus fortunei.
;
_journal_issue                   6
_journal_name_full               'Journal of natural products'
_journal_page_first              1565
_journal_page_last               1575
_journal_paper_doi               10.1021/acs.jnatprod.9b00059
_journal_volume                  82
_journal_year                    2019
_chemical_absolute_configuration ad
_chemical_formula_sum            'C19 H20 O4'
_chemical_formula_weight         312.35
_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
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.0950(2)
_cell_length_b                   9.6876(2)
_cell_length_c                   22.3117(5)
_cell_measurement_reflns_used    9815
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      140.020
_cell_measurement_theta_min      11.900
_cell_volume                     1533.56(6)
_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-2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.979
_diffrn_measured_fraction_theta_max 0.994
_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  0.0438
_diffrn_reflns_av_unetI/netI     0.0193
_diffrn_reflns_Laue_measured_fraction_full 0.979
_diffrn_reflns_Laue_measured_fraction_max 0.994
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            27589
_diffrn_reflns_point_group_measured_fraction_full 0.980
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         66.979
_diffrn_reflns_theta_min         6.547
_exptl_absorpt_coefficient_mu    0.766
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6462
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.353
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             664
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.170
_exptl_crystal_size_min          0.120
_refine_diff_density_max         0.123
_refine_diff_density_min         -0.103
_refine_diff_density_rms         0.024
_refine_ls_abs_structure_details
; 
 Flack x determined using 1050 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons and Flack (2004), Acta Cryst. A60, s61). 
;
_refine_ls_abs_structure_Flack   -0.04(6)
_refine_ls_extinction_coef       0.0071(18)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     212
_refine_ls_number_reflns         2731
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.052
_refine_ls_R_factor_all          0.0345
_refine_ls_R_factor_gt           0.0329
_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^)+(0.0518P)^2^+0.1587P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0892
_refine_ls_wR_factor_ref         0.0910
_reflns_Friedel_coverage         0.709
_reflns_Friedel_fraction_full    0.982
_reflns_Friedel_fraction_max     0.999
_reflns_number_gt                2620
_reflns_number_total             2731
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            np9b00059_si_002.cif
_cod_data_source_block           cu_d8v18103_0m
_cod_database_code               1552663
_shelx_estimated_absorpt_t_min   0.862
_shelx_estimated_absorpt_t_max   0.914
_shelxl_version_number           2013-4
_shelx_res_checksum              22665
_shelx_hkl_checksum              61113