Enantioselective Total Syntheses of Omuralide, 7-epi-Omuralide, and (+)-Lactacystin
Christopher J. Hayes; Alexandra E. Sherlock; Martin P. Green; Claire Wilson; Alexander J. Blake; Matthew D. Selby; Jeremy C. Prodger; Journal of Organic Chemistry 73 (2008) 2041–2051; doi:10.1021/jo7027695

data_4023355
_publ_section_title
;
 Enantioselective Total Syntheses of Omuralide, 7-epi-Omuralide,
 and (+)-Lactacystin
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              2041
_journal_page_last               2051
_journal_paper_doi               10.1021/jo7027695
_journal_volume                  73
_journal_year                    2008
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C17 H23 N O5'
_chemical_formula_sum            'C17 H23 N O5'
_chemical_formula_weight         321.36
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens
;
N-H and O-H from delta-F; 
methyl H atoms from delta-F; 
others placed geometrically
;
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'enCIFer editing of SHELXL97 CIF output'
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.0582(3)
_cell_length_b                   13.2390(6)
_cell_length_c                   20.3127(9)
_cell_measurement_reflns_used    13358
_cell_measurement_temperature    130(2)
_cell_measurement_theta_max      71.01
_cell_measurement_theta_min      3.34
_cell_volume                     1629.17(13)
_computing_cell_refinement       'CrysAlis, Oxford Diffraction Ltd.'
_computing_data_collection       'CrysAlis, Oxford Diffraction Ltd.'
_computing_data_reduction        'CrysAlis, Oxford Diffraction Ltd.'
_computing_publication_material
'enCIFer (Allen et al., 2004; PLATON (Spek, 2003)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      130(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type
'Oxford Diffraction PX Ultra CCD diffractometer'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enhance Ultra (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.5418
_diffrn_reflns_av_R_equivalents  0.018
_diffrn_reflns_av_sigmaI/netI    0.010
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            16259
_diffrn_reflns_theta_full        70.92
_diffrn_reflns_theta_max         70.92
_diffrn_reflns_theta_min         3.99
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.795
_exptl_absorpt_correction_T_max  1.0
_exptl_absorpt_correction_T_min  0.93
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlis, Oxford Diffraction Ltd.; Empirical absorption correction 
using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.310
_exptl_crystal_description       column
_exptl_crystal_F_000             688
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.24
_refine_diff_density_min         -0.14
_refine_diff_density_rms         0.03
_refine_ls_abs_structure_details
'Flack, H. D. (1983), Acta Cryst. A39, 876--881'
_refine_ls_abs_structure_Flack   0.05(13)
_refine_ls_extinction_coef       0.0028(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   1.05
_refine_ls_hydrogen_treatment
;
N-H and O-H refined freely;
methyl H atoms as part of rigid rotating group;
others as part of a riding model
;
_refine_ls_matrix_type           full
_refine_ls_number_parameters     239
_refine_ls_number_reflns         3115
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.05
_refine_ls_R_factor_all          0.0274
_refine_ls_R_factor_gt           0.0265
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.038P)^2^+0.390P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0684
_refine_ls_wR_factor_ref         0.0689
_reflns_number_gt                3010
_reflns_number_total             3115
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            jo7027695-File002.cif
_cod_data_source_block           FUREST_Cu
_cod_database_code               4023355