Bis-lactim ethers of cyclic dipeptides. 2. Benzyl-substituted compounds
Bolte, Michael; Benecke, Bernd; Egert, Ernst; Acta Crystallographica Section C 55 (1999) 968–973; doi:10.1107/S010827019801645X

data_2008638
_publ_section_title
;
 Bis-lactim ethers of cyclic dipeptides. 2. Benzyl-substituted
 compounds
;
_journal_issue                   6
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              968
_journal_page_last               973
_journal_paper_doi               10.1107/S010827019801645X
_journal_volume                  55
_journal_year                    1999
_chemical_formula_sum            'C20 H22 N2 O2'
_chemical_formula_weight         322.40
_chemical_name_systematic
;
(3RS,6SR)-3,6-Dibenzyl-2,5-dimethoxy-3,6-dihydro-pyrazine
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_audit_creation_method           SHELXL
_cell_angle_alpha                90.00
_cell_angle_beta                 90.050(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   5.8030(10)
_cell_length_b                   10.4860(10)
_cell_length_c                   14.7620(10)
_cell_measurement_reflns_used    44
_cell_measurement_temperature    293
_cell_measurement_theta_max      15
_cell_measurement_theta_min      10
_cell_volume                     898.27(19)
_computing_cell_refinement       D4
_computing_data_collection       'D4 (Clegg, 1981)'
_computing_data_reduction        'REDU4 (Stoe & Cie, 1988)'
_computing_molecular_graphics    'XP (Sheldrick, 1991)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS86 (Sheldrick, 1985)'
_diffrn_ambient_temperature      293
_diffrn_measurement_device       'Stoe Siemens four-circle diffractometer'
_diffrn_measurement_method       '\w-\q scans with learnt profile (Clegg, 1981)'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0096
_diffrn_reflns_av_sigmaI/netI    0.0113
_diffrn_reflns_limit_h_max       1
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            1867
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         3.77
_diffrn_standards_decay_%        3
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.077
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.192
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             344
_exptl_crystal_size_max          0.8
_exptl_crystal_size_mid          0.5
_exptl_crystal_size_min          0.4
_refine_diff_density_max         0.140
_refine_diff_density_min         -0.109
_refine_ls_extinction_coef       0.048(5)
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 1997)'
_refine_ls_goodness_of_fit_all   1.041
_refine_ls_goodness_of_fit_obs   1.088
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     110
_refine_ls_number_reflns         1588
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.041
_refine_ls_restrained_S_obs      1.088
_refine_ls_R_factor_all          0.0426
_refine_ls_R_factor_obs          .0369
_refine_ls_shift/esd_max         0.000
_refine_ls_shift/esd_mean        0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0519P)^2^+0.1374P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_all         0.1076
_refine_ls_wR_factor_obs         .1025
_reflns_number_observed          1337
_reflns_number_total             1588
_reflns_observed_criterion       I>2\s(I)
_cod_data_source_file            sk1255.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_refine_ls_weighting_scheme' value 'calc w =
1/[\s^2^(Fo^2^)+(0.0519P)^2^+0.1374P] 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^)+(0.0519P)^2^+0.1374P] 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      'P 21/n'
_cod_database_code               2008638
_cod_database_fobs_code          2008638