Isolation, Structure Elucidation, and Absolute Configuration of Highly Oxygenated Germacranolides from Carpesium cernuum.
Liu, Qing-Xin; Yang, Yong-Xun; Zhang, Jian-Ping; Chen, Li-Ping; Shen, Yun-Heng; Li, Hui-Liang; Zhang, Wei-Dong; Journal of natural products 79 (2016) 2479–2486; doi:10.1021/acs.jnatprod.6b00315

data_1544487
_publ_section_title
;
 Isolation, Structure Elucidation, and Absolute Configuration of Highly
 Oxygenated Germacranolides from Carpesium cernuum.
;
_journal_issue                   10
_journal_name_full               'Journal of natural products'
_journal_page_first              2479
_journal_page_last               2486
_journal_paper_doi               10.1021/acs.jnatprod.6b00315
_journal_volume                  79
_journal_year                    2016
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C20 H28 O8, 2(H2 O)'
_chemical_formula_sum            'C20 H32 O10'
_chemical_formula_weight         432.45
_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   mixed
_atom_sites_solution_primary     direct
_audit_creation_date             2015-04-21
_audit_creation_method
;
Olex2 1.2
(compiled 2015.01.26 svn.r3150 for OlexSys, GUI svn.r4998)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   10.3232(2)
_cell_length_b                   11.0194(2)
_cell_length_c                   19.2565(3)
_cell_measurement_reflns_used    7698
_cell_measurement_temperature    130
_cell_measurement_theta_max      69.14
_cell_measurement_theta_min      4.59
_cell_volume                     2190.53(7)
_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  'XL (Sheldrick, 2008)'
_computing_structure_solution    'ShelXS (Sheldrick, 2008)'
_diffrn_ambient_temperature      130
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.976
_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  0.0355
_diffrn_reflns_av_unetI/netI     0.0298
_diffrn_reflns_Laue_measured_fraction_full 0.988
_diffrn_reflns_Laue_measured_fraction_max 0.976
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            14167
_diffrn_reflns_point_group_measured_fraction_full 0.983
_diffrn_reflns_point_group_measured_fraction_max 0.963
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         69.394
_diffrn_reflns_theta_min         4.592
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.887
_exptl_absorpt_correction_T_max  0.7532
_exptl_absorpt_correction_T_min  0.6397
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.1150 before and 0.0498 after correction.
The Ratio of minimum to maximum transmission is 0.8493.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.311
_exptl_crystal_description       block
_exptl_crystal_F_000             928
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.231
_refine_diff_density_min         -0.227
_refine_diff_density_rms         0.035
_refine_ls_abs_structure_details
;
 Flack x determined using 1617 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.12(6)
_refine_ls_extinction_coef       0.0011(3)
_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   1.085
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     323
_refine_ls_number_reflns         3972
_refine_ls_number_restraints     87
_refine_ls_restrained_S_all      1.096
_refine_ls_R_factor_all          0.0337
_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^)+(0.0400P)^2^+0.5142P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0855
_refine_ls_wR_factor_ref         0.0861
_reflns_Friedel_coverage         0.727
_reflns_Friedel_fraction_full    0.976
_reflns_Friedel_fraction_max     0.945
_reflns_number_gt                3874
_reflns_number_total             3972
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            np6b00315_si_004.cif
_cod_data_source_block           cu_dm15162_0m
_cod_database_code               1544487
_shelxl_version_number           2014-3
_shelx_estimated_absorpt_t_max   0.949
_shelx_estimated_absorpt_t_min   0.843
_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, All O(H,H) groups
2. Restrained distances
 C2'-C3'
 1.29 with sigma of 0.01
 C2'-C5'
 1.52 with sigma of 0.01
 C3A-C4A
 1.53 with sigma of 0.01
3. Uiso/Uaniso restraints and constraints
C2' \\sim C3' \\sim C4' \\sim C5' \\sim C2A \\sim C3A \\sim C4A \\sim C5A:
within 1.7A with sigma of 0.005 and sigma for terminal atoms of 0.01
4. Others
 Fixed Sof: C2'(0.65) C3'(0.65) H3'(0.65) C4'(0.65) H4'A(0.65) H4'B(0.65)
 H4'C(0.65) C5'(0.65) H5'A(0.65) H5'B(0.65) H5'C(0.65) C2A(0.35) C3A(0.35)
 H3AA(0.35) C4A(0.35) H4AA(0.35) H4AB(0.35) H4AC(0.35) C5A(0.35) H5AA(0.35)
 H5AB(0.35) H5AC(0.35)
5.a Free rotating group:
 O2S(H2SA,H2SB), O1S(H1SA,H1SB)
5.b Ternary CH refined with riding coordinates:
 C2(H2A), C5(H5), C6(H6), C7(H7), C8(H8A), C10(H10)
5.c Secondary CH2 refined with riding coordinates:
 C1(H1A,H1B), C3(H3A,H3B)
5.d Aromatic/amide H refined with riding coordinates:
 C3'(H3'), C3A(H3AA)
5.e X=CH2 refined with riding coordinates:
 C13(H13A,H13B)
5.f Idealised Me refined as rotating group:
 C14(H14A,H14B,H14C), C15(H15A,H15B,H15C), C4'(H4'A,H4'B,H4'C), C5'(H5'A,H5'B,
 H5'C), C4A(H4AA,H4AB,H4AC), C5A(H5AA,H5AB,H5AC)
5.g Idealised tetrahedral OH refined as rotating group:
 O2(H2), O3(H3), O8(H8)
;
_shelx_res_checksum              22728
_shelx_hkl_checksum              6160
_olex2_submission_special_instructions 'No special instructions were received'