A unified approach to ent-atisane diterpenes and related alkaloids: synthesis of (-)-methyl atisenoate, (-)-isoatisine, and the hetidine skeleton.
Cherney, Emily C.; Lopchuk, Justin M.; Green, Jason C.; Baran, Phil S.; Journal of the American Chemical Society 136 (2014) 12592–12595; doi:10.1021/ja507321j

data_4122507
_publ_section_title
;
 A unified approach to ent-atisane diterpenes and related alkaloids:
 synthesis of (-)-methyl atisenoate, (-)-isoatisine, and the hetidine
 skeleton.
;
_journal_issue                   36
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              12592
_journal_page_last               12595
_journal_paper_doi               10.1021/ja507321j
_journal_volume                  136
_journal_year                    2014
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C21 H32 O2'
_chemical_formula_sum            'C21 H32 O2'
_chemical_formula_weight         316.46
_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_date             2014-03-24
_audit_creation_method
;
Olex2 1.2-beta
(compiled 2014.03.20 svn.r2914 for OlexSys, GUI svn.r4813)
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.3343(2)
_cell_length_b                   9.0194(3)
_cell_length_c                   26.3328(8)
_cell_measurement_reflns_used    9901
_cell_measurement_temperature    100
_cell_measurement_theta_max      70.174
_cell_measurement_theta_min      3.357
_cell_volume                     1741.94(9)
_computing_cell_refinement       'SAINT v8.34A (Bruker, 2013)'
_computing_data_collection       'APEX2 v2013.6-2 (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, 2008)'
_computing_structure_solution    'ShelXT (Sheldrick, 2008)'
_diffrn_ambient_temperature      100.0
_diffrn_detector                 'Bruker APEX CCD'
_diffrn_detector_area_resol_mean 8.0
_diffrn_detector_type            'CCD Area Detector'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device       'Fixed Chi Three-Circle Diffractometer'
_diffrn_measurement_device_type  'Bruker D8 APEX'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  'Multilayer Mirrors'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0345
_diffrn_reflns_av_unetI/netI     0.0250
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            22386
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        68.000
_diffrn_reflns_theta_max         70.167
_diffrn_reflns_theta_min         3.357
_diffrn_source                   'Micro Focus Rotating Anode'
_diffrn_source_type              'Bruker FR-591'
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.578
_exptl_absorpt_correction_T_max  0.3221
_exptl_absorpt_correction_T_min  0.2282
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2012/1 (Bruker,2012) was used for absorption correction.
wR2(int) was 0.0834 before and 0.0548 after correction.
The Ratio of minimum to maximum transmission is 0.7085.
The \l/2 correction factor is 0.0015.
;
_exptl_crystal_colour            Colorless
_exptl_crystal_colour_primary    Colorless
_exptl_crystal_density_diffrn    1.207
_exptl_crystal_description       Block
_exptl_crystal_F_000             696
_exptl_crystal_size_max          0.257
_exptl_crystal_size_mid          0.213
_exptl_crystal_size_min          0.185
_refine_diff_density_max         0.162
_refine_diff_density_min         -0.193
_refine_diff_density_rms         0.045
_refine_ls_abs_structure_details
;
 Flack x determined using 1348 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.06(7)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.057
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     211
_refine_ls_number_reflns         3277
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.057
_refine_ls_R_factor_all          0.0321
_refine_ls_R_factor_gt           0.0318
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0464P)^2^+0.3011P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0809
_refine_ls_wR_factor_ref         0.0812
_reflns_Friedel_coverage         0.710
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.989
_reflns_number_gt                3249
_reflns_number_total             3277
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja507321j_si_002.cif
_cod_data_source_block           Baran399
_cod_depositor_comments
;
The following automatic conversions were performed:

'_diffrn_radiation_probe' value 'X-ray' changed to 'x-ray' according
to
/home/saulius/struct/COD-crude-data--automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 2281 2013-09-26 08:29:07Z andrius 

 Adding full bibliography for 4122504--4122507.cif.
;
_cod_database_code               4122507
_shelxl_version_number           2014-3
_shelx_estimated_absorpt_t_max   0.901
_shelx_estimated_absorpt_t_min   0.866
_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:
 C7(H7), C11(H11), C13(H13)
2.b Secondary CH2 refined with riding coordinates:
 C3(H3A,H3B), C4(H4A,H4B), C5(H5A,H5B), C8(H8A,H8B), C9(H9A,H9B), C12(H12A,
 H12B), C14(H14A,H14B), C15(H15A,H15B), C18(H18A,H18B)
2.c X=CH2 refined with riding coordinates:
 C20(H20A,H20B)
2.d Idealised Me refined as rotating group:
 C16(H16A,H16B,H16C), C17(H17A,H17B,H17C), C21(H21A,H21B,H21C)
;
_shelx_res_checksum              62190
_shelx_hkl_checksum              96160