Synthetic Access to 3-Substituted Pyroglutamic Acids from Tetramate Derivatives of Serine, Threonine, <i>allo</i>-Threonine, and Cysteine.
Bagum, Halima; Christensen, Kirsten E.; Genov, Miroslav; Pretsch, Alexander; Pretsch, Dagmar; Moloney, Mark G.; The Journal of organic chemistry 84 (2019) 10257–10279; doi:10.1021/acs.joc.9b01432

data_4033999
_publ_section_title
;
 Synthetic Access to 3-Substituted Pyroglutamic Acids from Tetramate
 Derivatives of Serine, Threonine, <i>allo</i>-Threonine, and Cysteine.
;
_journal_issue                   16
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              10257
_journal_page_last               10279
_journal_paper_doi               10.1021/acs.joc.9b01432
_journal_volume                  84
_journal_year                    2019
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C20 H25 N O5'
_chemical_formula_sum            'C20 H25 N O5'
_chemical_formula_weight         359.42
_chemical_melting_point          ?
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_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   difmap
_atom_sites_solution_primary     other
_audit_creation_date             2017-03-28
_audit_creation_method           CRYSTALS_ver_14.61_build_6156
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   7.9339(2)
_cell_length_b                   9.5184(2)
_cell_length_c                   50.1703(12)
_cell_measurement_reflns_used    13890
_cell_measurement_temperature    150
_cell_measurement_theta_max      76
_cell_measurement_theta_min      5
_cell_volume                     3788.76(15)
_computing_cell_refinement       'CrysAlisPro, (Agilent, 2011)'
_computing_data_collection       'SuperNova, (Oxford Diffraction, 2010)'
_computing_data_reduction        'CrysAlisPro, (Agilent, 2011)'
_computing_molecular_graphics    'CAMERON (Watkin et al., 1996)'
_computing_publication_material  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_refinement  'CRYSTALS (Betteridge et al., 2003)'
_computing_structure_solution    'Superflip (Palatinus & Chapuis, 2007)'
_diffrn_ambient_temperature      150
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device       Area
_diffrn_measurement_device_type  'Oxford Diffraction SuperNova'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.031
_diffrn_reflns_av_sigmaI/netI    0.0446
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       46
_diffrn_reflns_limit_l_min       -62
_diffrn_reflns_number            30996
_diffrn_reflns_theta_full        73.607
_diffrn_reflns_theta_max         76.416
_diffrn_reflns_theta_min         4.729
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.741
_exptl_absorpt_correction_T_max  0.96
_exptl_absorpt_correction_T_min  0.74
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'CrysAlisPro, (Agilent, 2011)'
_exptl_crystal_colour            clear_pale_colourless
_exptl_crystal_density_diffrn    1.260
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       rod
_exptl_crystal_F_000             1536
_exptl_crystal_size_max          0.38
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.27
_refine_diff_density_min         -0.21
_refine_ls_abs_structure_details 'Flack (1983), 3342 Friedel-pairs'
_refine_ls_abs_structure_Flack   0.02(15)
_refine_ls_extinction_coef       36.0(17)
_refine_ls_extinction_method     'Larson (1970), Equation 22'
_refine_ls_goodness_of_fit_ref   0.9965
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     471
_refine_ls_number_reflns         7836
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0401
_refine_ls_R_factor_gt           0.0388
_refine_ls_shift/su_max          0.0009532
_refine_ls_shift/su_mean         0.0000709
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
;
 Method, part 1, Chebychev polynomial, (Watkin, 1994, Prince, 1982) 
 [weight] = 1.0/[A~0~*T~0~(x)+A~1~*T~1~(x) ... +A~n-1~]*T~n-1~(x)] 
 where A~i~ are the Chebychev coefficients listed below and x= Fcalc/Fmax 
 Method = Robust Weighting (Prince, 1982) 
 W = [weight] * [1-(deltaF/6*sigmaF)^2^]^2^ 
 A~i~ are: 
 0.109E+04 0.164E+04 946. 409. 84.6 
;
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.0737
_refine_ls_wR_factor_gt          0.0735
_refine_ls_wR_factor_ref         0.0737
_reflns_limit_h_max              9
_reflns_limit_h_min              -9
_reflns_limit_k_max              11
_reflns_limit_k_min              0
_reflns_limit_l_max              62
_reflns_limit_l_min              0
_reflns_number_gt                7569
_reflns_number_total             7836
_reflns_threshold_expression     I>2.0\s(I)
_oxford_diffrn_Wilson_B_factor   2.20
_oxford_diffrn_Wilson_scale      0.05
_oxford_refine_ls_r_factor_ref   0.0401
_oxford_refine_ls_scale          4.37(3)
_oxford_reflns_number_all        7836
_oxford_reflns_threshold_expression_ref I>-3.0\s(I)
_oxford_structure_analysis_title 6729
_cod_data_source_file            jo9b01432_si_002.cif
_cod_data_source_block           6bi
_cod_depositor_comments
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The following automatic conversions were performed:

data item '_chemical_melting_point' value 'not measured' was changed
to '?' -- the value is undefined or not given.

data item '_atom_sites_solution_primary' value 'Other' was changed to
'other' in accordance with the
/home/data/users/saulius/crontab/automatic-downloads/current/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

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

Automatic conversion script
Id: cif_fix_values 6909 2019-04-08 15:41:33Z antanas 
;
_cod_original_sg_symbol_H-M      'P 21 21 21 '
_cod_database_code               4033999