Crassins A-H, Diterpenoids from the Roots of Croton crassifolius.
Yuan, Qing-Qing; Tang, Shuai; Song, Wei-Bin; Wang, Wen-Qiong; Huang, Min; Xuan, Li-Jiang; Journal of natural products 80 (2017) 254–260; doi:10.1021/acs.jnatprod.6b00425

data_1545197
_publ_section_title
;
 Crassins A-H, Diterpenoids from the Roots of Croton crassifolius.
;
_journal_issue                   2
_journal_name_full               'Journal of natural products'
_journal_page_first              254
_journal_page_last               260
_journal_paper_doi               10.1021/acs.jnatprod.6b00425
_journal_volume                  80
_journal_year                    2017
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C20 H20 O5'
_chemical_formula_sum            'C20 H20 O5'
_chemical_formula_weight         340.36
_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'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_date             2016-04-13
_audit_creation_method
;
Olex2 1.2-beta
(compiled 2015.11.10 svn.r3248 for OlexSys, GUI svn.r5133)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.7141(2)
_cell_length_b                   9.0869(2)
_cell_length_c                   20.7089(4)
_cell_measurement_reflns_used    2968
_cell_measurement_temperature    173
_cell_measurement_theta_max      68.540
_cell_measurement_theta_min      5.508
_cell_volume                     1639.82(6)
_computing_cell_refinement       'SAINT v7.68A (Bruker, 2009)'
_computing_data_reduction        'SAINT v7.68A (Bruker, 2009)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      173
_diffrn_measured_fraction_theta_full 0.984
_diffrn_measured_fraction_theta_max 0.975
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0332
_diffrn_reflns_av_unetI/netI     0.0332
_diffrn_reflns_Laue_measured_fraction_full 0.984
_diffrn_reflns_Laue_measured_fraction_max 0.975
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            8493
_diffrn_reflns_point_group_measured_fraction_full 0.977
_diffrn_reflns_point_group_measured_fraction_max 0.963
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.975
_diffrn_reflns_theta_min         5.508
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.813
_exptl_absorpt_correction_T_max  0.7532
_exptl_absorpt_correction_T_min  0.6583
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.0935 before and 0.0517 after correction.
The Ratio of minimum to maximum transmission is 0.8740.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.379
_exptl_crystal_description       block
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.205
_refine_diff_density_min         -0.212
_refine_diff_density_rms         0.042
_refine_ls_abs_structure_details
;
 Flack x determined using 1087 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.07(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.048
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     230
_refine_ls_number_reflns         2939
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.048
_refine_ls_R_factor_all          0.0396
_refine_ls_R_factor_gt           0.0369
_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^)+(0.0610P)^2^+0.1200P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0929
_refine_ls_wR_factor_ref         0.0950
_reflns_Friedel_coverage         0.702
_reflns_Friedel_fraction_full    0.968
_reflns_Friedel_fraction_max     0.948
_reflns_number_gt                2761
_reflns_number_total             2939
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            np6b00425_si_002.cif
_cod_data_source_block           cu_2016163_0m
_cod_depositor_comments
'Adding full bibliography for 1545197--1545198.cif.'
_cod_database_code               1545197
_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:
 C6(H6), C8(H8)
2.b Secondary CH2 refined with riding coordinates:
 C7(H7A,H7B), C3(H3A,H3B)
2.c Aromatic/amide H refined with riding coordinates:
 C16(H16), C14(H14), C11(H11), C15(H15)
2.d Idealised Me refined as rotating group:
 C20(H20A,H20B,H20C), C18(H18A,H18B,H18C), C17(H17A,H17B,H17C)
2.e Idealised tetrahedral OH refined as rotating group:
 O4(H4)
;
_shelx_shelxl_version_number     2014/7
_olex2_submission_special_instructions 'No special instructions were received'