Amide−N-Oxide Heterosynthon and Amide Dimer Homosynthon in Cocrystals of Carboxamide Drugs and PyridineN-Oxides
Babu, N. Jagadeesh; Reddy, L. Sreenivas; Nangia, Ashwini; Molecular Pharmaceutics 4 (2007) 417–; doi:10.1021/mp070014c

data_1505207
_publ_section_title
;
 Amide&#x2212;N-Oxide Heterosynthon and Amide Dimer Homosynthon in
 Cocrystals of Carboxamide Drugs and PyridineN-Oxides
;
_journal_issue                   3
_journal_name_full               'Molecular Pharmaceutics'
_journal_page_first              417
_journal_paper_doi               10.1021/mp070014c
_journal_volume                  4
_journal_year                    2007
_chemical_formula_moiety         ' C4 H4 N2 O3, 0.5(C4 H4 N2 O2)'
_chemical_formula_sum            'C6 H6 N3 O4'
_chemical_formula_weight         184.14
_chemical_name_systematic
; 
2:1 Cocrystal of Barbituric acid and 4,4'pyrazine-N,N'-dioxide
;
_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'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 95.795(8)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.258(3)
_cell_length_b                   6.478(3)
_cell_length_c                   22.118(11)
_cell_measurement_reflns_used    4820
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      26.27
_cell_measurement_theta_min      3.28
_cell_volume                     749.5(7)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0238
_diffrn_reflns_av_sigmaI/netI    0.0173
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            7435
_diffrn_reflns_theta_full        26.27
_diffrn_reflns_theta_max         26.27
_diffrn_reflns_theta_min         1.85
_exptl_absorpt_coefficient_mu    0.140
_exptl_absorpt_correction_T_max  0.9726
_exptl_absorpt_correction_T_min  0.9360
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Bruker AXS SADABS program'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.632
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             380
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.41
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.180
_refine_diff_density_min         -0.311
_refine_diff_density_rms         0.081
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.064
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     126
_refine_ls_number_reflns         1511
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.064
_refine_ls_R_factor_all          0.0464
_refine_ls_R_factor_gt           0.0434
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0555P)^2^+0.2413P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1053
_refine_ls_wR_factor_ref         0.1079
_reflns_number_gt                1390
_reflns_number_total             1511
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            mp070014csi20070123_112315.cif
_cod_data_source_block           an627_m
_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_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        749.4(7)
_cod_original_sg_symbol_H-M      'P2(1)/n  '
_cod_database_code               1505207