A new synthetic approach to (+)-lactacystin based on radical cyclisation of enantiopure α-ethynyl substituted serine derivatives to 4-methylenepyrrolidinones
Pattenden, Gerald; Rescourio, Gwenaëlla; Organic & Biomolecular Chemistry 6 (2008) 3428–3438; doi:10.1039/b806681g

data_7150958
_publ_section_title
;
 A new synthetic approach to (+)-lactacystin based on radical
 cyclisation of enantiopure \a-ethynyl substituted serine derivatives
 to 4-methylenepyrrolidinones
;
_journal_issue                   18
_journal_name_full               'Organic &amp; Biomolecular Chemistry'
_journal_page_first              3428
_journal_page_last               3438
_journal_paper_doi               10.1039/b806681g
_journal_volume                  6
_journal_year                    2008
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C13 H20 Cl3 N O2 Si'
_chemical_formula_sum            'C13 H20 Cl3 N O2 Si'
_chemical_formula_weight         356.74
_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   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.030(2)
_cell_length_b                   10.027(2)
_cell_length_c                   22.837(5)
_cell_measurement_reflns_used    1366
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      23.95
_cell_measurement_theta_min      2.7
_cell_volume                     1838.8(7)
_computing_cell_refinement       'Bruker SAINT version 6.36a (Bruker, 2000)'
_computing_data_collection       'Bruker SMART version 5.625 (Bruker, 2001)'
_computing_data_reduction        'Bruker SAINT; Bruker SHELXTL (Bruker, 2001)'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material
'SHELXL-97; enCIFer (CCDC, 2003); PLATON (Spek, 2003)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker SMART APEX CCD area detector'
_diffrn_measurement_method       omega
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.061
_diffrn_reflns_av_sigmaI/netI    0.101
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            9295
_diffrn_reflns_theta_full        25.04
_diffrn_reflns_theta_max         25.04
_diffrn_reflns_theta_min         2.22
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.564
_exptl_absorpt_correction_T_max  0.889
_exptl_absorpt_correction_T_min  0.785
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SHELXTL version 6.12; Bruker, 2001)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.289
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       column
_exptl_crystal_F_000             744
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.07
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.18
_refine_diff_density_min         -0.18
_refine_diff_density_rms         0.04
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.01(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.77
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     209
_refine_ls_number_reflns         3231
_refine_ls_number_restraints     30
_refine_ls_restrained_S_all      0.80
_refine_ls_R_factor_all          0.0703
_refine_ls_R_factor_gt           0.0373
_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^)+(0.007P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0447
_refine_ls_wR_factor_ref         0.0488
_reflns_number_gt                1948
_reflns_number_total             3231
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b806681g.txt
_cod_data_source_block           ISOXCL
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_cell_volume        1838.8(11)
_cod_database_code               7150958