Rare Cembranoids from Chinese Soft Coral Sarcophyton ehrenbergi: Structural and Stereochemical Studies.
Li, Geng; Li, Heng; Zhang, Quan; Yang, Min; Gu, Yu-Cheng; Liang, Lin-Fu; Tang, Wei; Guo, Yue-Wei; The Journal of organic chemistry 84 (2019) 5091–5098; doi:10.1021/acs.joc.9b00030

data_4034358
_publ_section_title
;
 Rare Cembranoids from Chinese Soft Coral Sarcophyton ehrenbergi:
 Structural and Stereochemical Studies.
;
_journal_issue                   9
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              5091
_journal_page_last               5098
_journal_paper_doi               10.1021/acs.joc.9b00030
_journal_volume                  84
_journal_year                    2019
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C20 H28 O2'
_chemical_formula_sum            'C20 H28 O2'
_chemical_formula_weight         300.42
_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
_atom_sites_solution_primary     dual
_audit_creation_date             2018-03-09
_audit_creation_method
;
Olex2 1.2-alpha
(compiled 2018.02.02 svn.r3481 for OlexSys, GUI svn.r5470)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   6.3002(4)
_cell_length_b                   12.8333(6)
_cell_length_c                   22.1179(10)
_cell_measurement_reflns_used    1693
_cell_measurement_temperature    173
_cell_measurement_theta_max      68.93
_cell_measurement_theta_min      8.81
_cell_volume                     1788.28(16)
_computing_cell_refinement       'SAINT v8.34A (Bruker, 2013)'
_computing_data_reduction        'SAINT v8.34A (Bruker, 2013)'
_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      173.0
_diffrn_measured_fraction_theta_full 0.977
_diffrn_measured_fraction_theta_max 0.977
_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  0.0442
_diffrn_reflns_av_unetI/netI     0.0247
_diffrn_reflns_Laue_measured_fraction_full 0.977
_diffrn_reflns_Laue_measured_fraction_max 0.977
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            20108
_diffrn_reflns_point_group_measured_fraction_full 0.968
_diffrn_reflns_point_group_measured_fraction_max 0.968
_diffrn_reflns_theta_full        66.594
_diffrn_reflns_theta_max         66.594
_diffrn_reflns_theta_min         3.982
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.542
_exptl_absorpt_correction_T_max  0.7532
_exptl_absorpt_correction_T_min  0.6588
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'SADABS-2014/5 (Bruker,2014/5) was used for absorption correction. wR2(int) was 0.1340 before and 0.0585 after correction. The Ratio of minimum to maximum transmission is 0.8747. The \l/2 correction factor is 0.00150.'
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.116
_exptl_crystal_description       block
_exptl_crystal_F_000             656
_exptl_crystal_size_max          0.32
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.132
_refine_diff_density_min         -0.109
_refine_diff_density_rms         0.024
_refine_ls_abs_structure_details
;
 Flack x determined using 1134 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.09(8)
_refine_ls_extinction_coef       0.0134(9)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   1.048
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     204
_refine_ls_number_reflns         3056
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.048
_refine_ls_R_factor_all          0.0322
_refine_ls_R_factor_gt           0.0301
_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^)+(0.0476P)^2^+0.1159P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0801
_refine_ls_wR_factor_ref         0.0815
_reflns_Friedel_coverage         0.692
_reflns_Friedel_fraction_full    0.955
_reflns_Friedel_fraction_max     0.955
_reflns_number_gt                2875
_reflns_number_total             3056
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo9b00030_si_002.cif
_cod_data_source_block           cu_20180178_0m
_cod_database_code               4034358
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_max   0.938
_shelx_estimated_absorpt_t_min   0.846
_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
2.a Ternary CH refined with riding coordinates:
 C6(H6), C15(H15)
2.b Secondary CH2 refined with riding coordinates:
 C14(H14A,H14B), C13(H13A,H13B), C5(H5A,H5B), C9(H9A,H9B), C10(H10A,H10B)
2.c Aromatic/amide H refined with riding coordinates:
 C7(H7), C3(H3), C2(H2), C11(H11)
2.d Idealised Me refined as rotating group:
 C18(H18A,H18B,H18C), C20(H20A,H20B,H20C), C17(H17A,H17B,H17C), C16(H16A,H16B,
 H16C)
;
_olex2_submission_special_instructions 'No special instructions were received'