Reactive Intermediates in Peptide Synthesis: First Crystal Structures and ab Initio Calculations of 2-Alkoxy-5(4H)-oxazolones from Urethane-Protected Amino Acids
Marco Crisma; Giovanni Valle; Fernando Formaggio; Claudio Toniolo; Alessandro Bagno; Journal of the American Chemical Society 119 (1997) 4136–4142; doi:10.1021/ja9637863

data_4116962
_publ_section_title
;
 Reactive Intermediates in Peptide Synthesis: First Crystal Structures and
 ab Initio Calculations of 2-Alkoxy-5(4H)-oxazolones from
 Urethane-Protected Amino Acids
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              4136
_journal_page_last               4142
_journal_paper_doi               10.1021/ja9637863
_journal_volume                  119
_journal_year                    1997
_chemical_compound_source
;                                                                               
 Crystallization from ethyl acetate by slow evaporation                         
;
_chemical_formula_sum            'C18 H23 N2 O4'
_chemical_formula_weight         331.39
_chemical_name_common
;                                                                               
 5(4H)-oxazolone from Z-TOAC-OH                                                 
;
_chemical_name_systematic        ?
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
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_symmetry_space_group_name_Hall  '-P 2yn'
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_cell_angle_alpha                90.
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_cell_angle_gamma                90.
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_computing_structure_solution    'SHELXS 86'
_diffrn_ambient_temperature      293(2)
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_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
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_diffrn_reflns_limit_h_max       15
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_exptl_crystal_colour            orange
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_exptl_crystal_description
;                                                                               
 prism                                                                          
;
_exptl_crystal_F_000             708.00
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_refine_ls_shift/esd_max         0.69
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_refine_ls_weighting_details     'w = 1/[\s^2(F)+0.0016(F^2)]'
_refine_ls_weighting_scheme      calc
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;
The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value '1/[\s^2(F)+0.0016(F^2)]' 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(F)+0.0016(F^2)]'.

Automatic conversion script
Id: cif_fix_values 3143 2015-03-26 13:38:13Z robertas 
;
_cod_original_cell_volume        1829(2)
_cod_database_code               4116962