Crystal structures of the two epimers from the unusual thermal C6-epimerization of 5-oxo-1,2,3,5,5a,6,7,9b-octahydro-7,9a-epoxypyrrolo[2,1-<i>a</i>]isoindole-6-carboxylic acid, 5a(<i>RS</i>),6(<i>SR</i>),7(<i>RS</i>),9a(<i>SR</i>),9b(<i>SR</i>) and 5a(<i>RS</i>),6(<i>RS</i>),7(<i>RS</i>),9a(<i>SR</i>),9b(<i>SR</i>)
Poplevin, Dmitry S.; Zubkov, Fedor I.; Dorovatovskii, Pavel V.; Zubavichus, Yan V.; Khrustalev, Victor N.; Acta Crystallographica Section E 72 (2016) 1429–1433; doi:10.1107/S2056989016014420

data_2241848
_publ_section_title
;
 Crystal structures of the two epimers from the unusual thermal
 C6-epimerization of
 5-oxo-1,2,3,5,5a,6,7,9b-octahydro-7,9a-epoxypyrrolo[2,1-<i>a</i>]isoindole-6-carboxylic
 acid, 5a(<i>RS</i>),6(<i>SR</i>),7(<i>RS</i>),9a(<i>SR</i>),9b(<i>SR</i>)
 and 5a(<i>RS</i>),6(<i>RS</i>),7(<i>RS</i>),9a(<i>SR</i>),9b(<i>SR</i>)
;
_journal_coeditor_code           ZS2368
_journal_issue                   10
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              1429
_journal_page_last               1433
_journal_paper_doi               10.1107/S2056989016014420
_journal_volume                  72
_journal_year                    2016
_chemical_formula_moiety         'C12 H13 N O4'
_chemical_formula_sum            'C12 H13 N O4'
_chemical_formula_weight         235.23
_chemical_melting_point_gt       414
_chemical_melting_point_lt       416
_chemical_name_systematic
'5a(<i>RS</i>),6(<i>RS</i>),7(<i>RS</i>),9a(<i>SR</i>),9b(<i>SR</i>)-5-Oxo-1,2,3,5,5a,6,7,9b-octahydro-7,9a-epoxypyrrolo[2,1-<i>a</i>]isoindole-6-carboxylic acid'
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     difmap
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014/6
_cell_angle_alpha                94.04(3)
_cell_angle_beta                 111.12(3)
_cell_angle_gamma                105.17(3)
_cell_formula_units_Z            2
_cell_length_a                   8.4700(17)
_cell_length_b                   8.5100(17)
_cell_length_c                   8.5900(17)
_cell_measurement_reflns_used    500
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      36.0
_cell_measurement_theta_min      3.6
_cell_volume                     548.0(3)
_computing_cell_refinement
;
<i>i</i>Mosflm (Battye <i>et al.</i>, 2011)
;
_computing_data_collection
;
<i>Automar</i> (MarXperts, 2015)
;
_computing_data_reduction
;
<i>i</i>Mosflm (Battye <i>et al.</i>, 2011)
;
_computing_molecular_graphics
;
SHELXTL (Sheldrick, 2008)
;
_computing_publication_material
;
SHELXTL (Sheldrick, 2008)
;
_computing_structure_refinement
;
SHELXL-2014 (Sheldrick, 2015)
;
_computing_structure_solution
;
SHELXS-97 (Sheldrick, 2008)
;
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.941
_diffrn_measured_fraction_theta_max 0.890
_diffrn_measurement_device_type  'MAR CCD'
_diffrn_measurement_method       '\f scan'
_diffrn_radiation_type           synchrotron
_diffrn_radiation_wavelength     0.96990
_diffrn_reflns_av_R_equivalents  0.0612
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            7090
_diffrn_reflns_theta_full        35.587
_diffrn_reflns_theta_max         38.131
_diffrn_reflns_theta_min         3.443
_exptl_absorpt_coefficient_mu    0.230
_exptl_absorpt_correction_T_max  0.969
_exptl_absorpt_correction_T_min  0.960
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
(<i>SCALA</i>; Evans, 2006)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.426
_exptl_crystal_description       prism
_exptl_crystal_F_000             248
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.454
_refine_diff_density_min         -0.359
_refine_ls_extinction_coef       0.138(11)
_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, 2015)
;
_refine_ls_goodness_of_fit_ref   0.928
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     155
_refine_ls_number_reflns         2104
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.928
_refine_ls_R_factor_all          0.1278
_refine_ls_R_factor_gt           0.0988
_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^)+(0.06P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2098
_refine_ls_wR_factor_ref         0.2404
_reflns_number_gt                1402
_reflns_number_total             2104
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            zs2368sup1.cif
_cod_data_source_block           IIa
_cod_original_cell_volume        548.0(2)
_cod_database_code               2241848
_cod_database_fobs_code          2241848
_shelx_estimated_absorpt_t_min   0.963
_shelx_estimated_absorpt_t_max   0.975
_shelx_hkl_checksum              21171
_shelx_res_checksum              93228
_shelxl_version_number           2014/6