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_1544489
_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         'C19 H28 O8, 2(H2 O)'
_chemical_formula_sum            'C19 H32 O10'
_chemical_formula_weight         420.44
_space_group_crystal_system      tetragonal
_space_group_IT_number           76
_space_group_name_Hall           'P 4w'
_space_group_name_H-M_alt        'P 41'
_symmetry_space_group_name_Hall  'P 4w'
_symmetry_space_group_name_H-M   'P 41'
_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                   10.23070(10)
_cell_length_b                   10.23070(10)
_cell_length_c                   20.5352(3)
_cell_measurement_reflns_used    6834
_cell_measurement_temperature    130
_cell_measurement_theta_max      69.215
_cell_measurement_theta_min      4.32
_cell_volume                     2149.36(4)
_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 0.976
_diffrn_measured_fraction_theta_max 0.967
_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  0.0382
_diffrn_reflns_av_unetI/netI     0.0307
_diffrn_reflns_Laue_measured_fraction_full 0.976
_diffrn_reflns_Laue_measured_fraction_max 0.967
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            16308
_diffrn_reflns_point_group_measured_fraction_full 0.848
_diffrn_reflns_point_group_measured_fraction_max 0.836
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         69.753
_diffrn_reflns_theta_min         4.321
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.888
_exptl_absorpt_correction_T_max  0.7532
_exptl_absorpt_correction_T_min  0.6613
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2008/1 (Bruker,2008) was used for absorption correction.
wR2(int) was 0.1350 before and 0.0527 after correction.
The Ratio of minimum to maximum transmission is 0.8780.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.299
_exptl_crystal_description       block
_exptl_crystal_F_000             904
_exptl_crystal_size_max          0.25
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.536
_refine_diff_density_min         -0.331
_refine_diff_density_rms         0.054
_refine_ls_abs_structure_details
;
 Flack x determined using 1293 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.06(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.049
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     278
_refine_ls_number_reflns         3411
_refine_ls_number_restraints     25
_refine_ls_restrained_S_all      1.123
_refine_ls_R_factor_all          0.0404
_refine_ls_R_factor_gt           0.0393
_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^)+(0.0713P)^2^+0.5336P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1042
_refine_ls_wR_factor_ref         0.1054
_reflns_Friedel_coverage         0.679
_reflns_Friedel_fraction_full    0.713
_reflns_Friedel_fraction_max     0.697
_reflns_number_gt                3311
_reflns_number_total             3411
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            np6b00315_si_003.cif
_cod_data_source_block           cu_dm15100_0m
_cod_original_cell_volume        2149.36(5)
_cod_database_code               1544489
_shelxl_version_number           2014-3
_shelx_estimated_absorpt_t_max   0.957
_shelx_estimated_absorpt_t_min   0.809
_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. Uiso/Uaniso restraints and constraints
C2' \\sim C3' \\sim C4': within 2A with sigma of 0.005 and sigma for terminal
atoms of 0.01
Uanis(C3') \\sim Ueq, Uanis(C4') \\sim Ueq: with sigma of 0.005 and sigma for
terminal atoms of 0.01
3.a Free rotating group:
 O2S(H2Sa,H2Sb), O1S(H1Sa,H1Sb)
3.b Ternary CH refined with riding coordinates:
 C2(H2a), C5(H5), C6(H6a), C7(H7), C8(H8), C10(H10), C2'(H2')
3.c Secondary CH2 refined with riding coordinates:
 C1(H1a,H1b), C3(H3a,H3b)
3.d X=CH2 refined with riding coordinates:
 C13(H13a,H13b)
3.e Idealised Me refined as rotating group:
 C14(H14a,H14b,H14c), C15(H15a,H15b,H15c), C3'(H3'a,H3'b,H3'c), C4'(H4'a,H4'b,
 H4'c)
3.f Idealised tetrahedral OH refined as rotating group:
 O2(H2), O6(H6)
;
_shelx_res_checksum              12659
_shelx_hkl_checksum              64899
_olex2_submission_special_instructions 'No special instructions were received'