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_1505210
_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         'C8 H12 N2 O3, 2(C6 H7 N O)'
_chemical_formula_sum            'C20 H26 N4 O5'
_chemical_formula_weight         402.45
_chemical_name_systematic
; 
 2:4 Cocrystal of Barbital acid and 4-methylpyridine N-oxide 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 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                 96.6700(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   8.2106(5)
_cell_length_b                   23.9166(15)
_cell_length_c                   20.6318(13)
_cell_measurement_reflns_used    3415
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      26.03
_cell_measurement_theta_min      2.64
_cell_volume                     4024.0(4)
_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 0.996
_diffrn_measured_fraction_theta_max 0.996
_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  0.0317
_diffrn_reflns_av_sigmaI/netI    0.0379
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       29
_diffrn_reflns_limit_k_min       -27
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            25727
_diffrn_reflns_theta_full        26.04
_diffrn_reflns_theta_max         26.04
_diffrn_reflns_theta_min         1.31
_exptl_absorpt_coefficient_mu    0.097
_exptl_absorpt_correction_T_max  0.9828
_exptl_absorpt_correction_T_min  0.9614
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'Bruker AXS SADABS program'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.329
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1712
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.18
_refine_diff_density_max         0.416
_refine_diff_density_min         -0.267
_refine_diff_density_rms         0.063
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.012
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     547
_refine_ls_number_reflns         7922
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.012
_refine_ls_R_factor_all          0.0988
_refine_ls_R_factor_gt           0.0537
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0881P)^2^+0.0664P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1406
_refine_ls_wR_factor_ref         0.1696
_reflns_number_gt                4351
_reflns_number_total             7922
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            mp070014csi20070123_112436.cif
_cod_data_source_block           nj474
_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_sg_symbol_H-M      P21/c
_cod_database_code               1505210