Unexpected formation of β-lactams and penem isosteres from mesoionics: sequential ring-opening–rearrangement of [3 + 2] cycloadducts
Avalos, Martín; Babiano, Reyes; Cintas, Pedro; Jiménez, José L.; López, Ignacio; Palacios, Juan C.; Hursthouse, Michael B.; Light, Mark E.; Chemical Communications  (1999) 1589–; doi:10.1039/a904333k

data_7115204
_publ_section_title
;
 Unexpected formation of \b-lactams and penem isosteres from mesoionics:
 sequential ring-opening--rearrangement of [3 + 2] cycloadducts
;
_journal_issue                   16
_journal_name_full               'Chemical Communications'
_journal_page_first              1589
_journal_paper_doi               10.1039/a904333k
_journal_year                    1999
_chemical_formula_sum            'C31 H28 N2 O3 S'
_chemical_formula_weight         508.61
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90
_cell_angle_beta                 92.1722(18)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.3385(3)
_cell_length_b                   22.6660(7)
_cell_length_c                   10.2516(4)
_cell_measurement_reflns_used    na
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      na
_cell_measurement_theta_min      na
_cell_volume                     2632.75(15)
_computing_cell_refinement       'DENZO and COLLECT'
_computing_data_collection
;
DENZO (Otwinowski and MInor, 1997), COLLECT (Hooft, 1998)
;
_computing_data_reduction        'DENZO and COLLECT'
_computing_molecular_graphics    ORTEP
_computing_publication_material  CIFTAB
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean '9.091 pixels/mm'
_diffrn_measured_fraction_theta_full 0.958
_diffrn_measured_fraction_theta_max 0.958
_diffrn_measurement_device_type  'Enraf Nonius KappaCCD area detector'
_diffrn_measurement_method       'Phi and Omega scans to fill Ewald sphere'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Enraf Nonius FR591 rotating anode'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0633
_diffrn_reflns_av_sigmaI/netI    0.0587
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       28
_diffrn_reflns_limit_k_min       -28
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            24655
_diffrn_reflns_theta_full        26.39
_diffrn_reflns_theta_max         26.39
_diffrn_reflns_theta_min         2.01
_diffrn_standards_decay_%        na
_diffrn_standards_interval_count na
_diffrn_standards_interval_time  na
_diffrn_standards_number         'not measured'
_exptl_absorpt_coefficient_mu    0.158
_exptl_absorpt_correction_T_max  0.9843
_exptl_absorpt_correction_T_min  0.9393
_exptl_absorpt_correction_type   'Empirical, SORTAV'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.283
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1072
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.226
_refine_diff_density_min         -0.271
_refine_diff_density_rms         0.051
_refine_ls_extinction_coef       yes
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.998
_refine_ls_hydrogen_treatment    refine
_refine_ls_matrix_type           full
_refine_ls_number_parameters     446
_refine_ls_number_reflns         5299
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.998
_refine_ls_R_factor_all          0.0765
_refine_ls_R_factor_gt           0.0443
_refine_ls_shift/su_max          0.007
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0663P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1031
_refine_ls_wR_factor_ref         0.1171
_reflns_number_gt                3671
_reflns_number_total             5299
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            904333k.txt
_cod_data_source_block           s92a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 

The following automatic conversions were performed:

'_symmetry_cell_setting' tag value 'Monoclinic P' was replaced with
'monoclinic' value as specified in the replacement file
'/home/robertas/cod-tools/perl-scripts/inputs/replacement_values.lst'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc
w=1/[\s^2^(Fo^2^)+(0.0663P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' was
changed to 'calc'. New tag '_refine_ls_weighting_details' was
created. The value of the new tag was set to
'w=1/[\s^2^(Fo^2^)+(0.0663P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_sg_symbol_H-M      P2(1)/c
_cod_database_code               7115204