Investigation of a route to ibotenic acid analogues via a reduced pyroglutamate template.
Ahmed, Omar; Hitchcock, Peter B.; Young, Douglas W.; Organic & biomolecular chemistry 4 (2006) 1596–1603; doi:10.1039/b600195e

data_7150439
_publ_section_title
;
 Investigation of a route to ibotenic acid analogues via a reduced
 pyroglutamate template.
;
_journal_issue                   8
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1596
_journal_page_last               1603
_journal_paper_doi               10.1039/b600195e
_journal_volume                  4
_journal_year                    2006
_chemical_absolute_configuration syn
_chemical_compound_source        'synthesis as described'
_chemical_formula_moiety         'C12 H19 N3 O4'
_chemical_formula_sum            'C12 H19 N3 O4'
_chemical_formula_weight         269.3
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_Int_Tables_number      19
_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_conform_dict_location     ftp://ftp.iucr.org/pub/cif_core.dic
_audit_conform_dict_name         cif_core.dic
_audit_conform_dict_version      2.3
_audit_creation_date             2006-02-10T17:27:29-00:00
_audit_creation_method           'WinGX routine CIF_UPDATE'
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   5.6733(2)
_cell_length_b                   11.5380(9)
_cell_length_c                   21.3149(16)
_cell_measurement_temperature    173(2)
_cell_volume                     1395.24(16)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor 1997)'
_computing_data_reduction
'HKL Denzo and Scalepack (Otwinowski & Minor 1997)'
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.989
_diffrn_measured_fraction_theta_max 0.989
_diffrn_measurement_device       KappaCCD
_diffrn_measurement_method       CCD
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.056
_diffrn_reflns_av_unetI/netI     0.062
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            5827
_diffrn_reflns_theta_full        25
_diffrn_reflns_theta_max         25
_diffrn_reflns_theta_min         3.72
_exptl_absorpt_coefficient_mu    0.097
_exptl_absorpt_correction_type   none
_exptl_crystal_density_diffrn    1.282
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             576
_exptl_crystal_size_max          0.4
_exptl_crystal_size_mid          0.3
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.182
_refine_diff_density_min         -0.208
_refine_diff_density_rms         0.052
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   4(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.063
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     173
_refine_ls_number_reflns         1449
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.063
_refine_ls_R_factor_all          0.0584
_refine_ls_R_factor_gt           0.0446
_refine_ls_shift/su_max          0
_refine_ls_shift/su_mean         0
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0513P)^2^+0.2565P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1003
_refine_ls_wR_factor_ref         0.1067
_reflns_number_gt                1208
_reflns_number_total             1449
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b600195e.txt
_cod_data_source_block           mar1401
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7150439