Mannolides A-C with an Intact Diterpenoid Skeleton Providing Insights on the Biosynthesis of Antitumor Cephalotaxus Troponoids.
Ni, Gang; Zhang, Hua; Fan, Yao-Yue; Liu, Hong-Chun; Ding, Jian; Yue, Jian-Min; Organic letters 18 (2016) 1880–1883; doi:10.1021/acs.orglett.6b00653

data_1543022
_publ_section_title
;
 Mannolides A-C with an Intact Diterpenoid Skeleton Providing Insights on
 the Biosynthesis of Antitumor Cephalotaxus Troponoids.
;
_journal_issue                   8
_journal_name_full               'Organic letters'
_journal_page_first              1880
_journal_page_last               1883
_journal_paper_doi               10.1021/acs.orglett.6b00653
_journal_volume                  18
_journal_year                    2016
_chemical_absolute_configuration ad
_chemical_formula_sum            'C20 H24 O4'
_chemical_formula_weight         328.39
_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'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.1625(2)
_cell_length_b                   7.7880(2)
_cell_length_c                   28.9103(7)
_cell_measurement_reflns_used    9891
_cell_measurement_temperature    153(2)
_cell_measurement_theta_max      65.69
_cell_measurement_theta_min      5.88
_cell_volume                     1612.66(7)
_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-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      153(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_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  0.0434
_diffrn_reflns_av_unetI/netI     0.0302
_diffrn_reflns_Laue_measured_fraction_full 0.992
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -29
_diffrn_reflns_number            21694
_diffrn_reflns_point_group_measured_fraction_full 0.992
_diffrn_reflns_point_group_measured_fraction_max 0.992
_diffrn_reflns_theta_full        66.488
_diffrn_reflns_theta_max         66.488
_diffrn_reflns_theta_min         3.057
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    0.751
_exptl_absorpt_correction_T_max  0.9706
_exptl_absorpt_correction_T_min  0.8060
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.353
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             704
_exptl_crystal_size_max          0.300
_exptl_crystal_size_mid          0.080
_exptl_crystal_size_min          0.040
_refine_diff_density_max         0.154
_refine_diff_density_min         -0.157
_refine_diff_density_rms         0.032
_refine_ls_abs_structure_details
;
 Flack x determined using 1106 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.02(7)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.019
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     238
_refine_ls_number_reflns         2835
_refine_ls_number_restraints     2
_refine_ls_restrained_S_all      1.020
_refine_ls_R_factor_all          0.0360
_refine_ls_R_factor_gt           0.0352
_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^)+(0.0661P)^2^+0.2246P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0992
_refine_ls_wR_factor_ref         0.1004
_reflns_Friedel_coverage         0.691
_reflns_Friedel_fraction_full    0.991
_reflns_Friedel_fraction_max     0.991
_reflns_number_gt                2758
_reflns_number_total             2835
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol6b00653_si_004.cif
_cod_data_source_block           cu_dm12145_0m
_cod_depositor_comments
'Adding full bibliography for 1543021--1543025.cif.'
_cod_database_code               1543022
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.806
_shelx_estimated_absorpt_t_max   0.971
_shelx_res_checksum              96521
_shelx_hkl_checksum              96044