Crystal structure of a 2:1 piroxicam–gentisic acid co-crystal featuring neutral and zwitterionic piroxicam molecules
Horstman, Elizabeth M.; Bertke, Jeffery A.; Woods, Toby J.; Kenis, Paul J. A.; Acta Crystallographica Section E 72 (2016) 1714–1717; doi:10.1107/S2056989016017321

data_2241932
_publ_contact_author
;
Toby J. Woods
University of Illinois
School of Chemical Sciences, Box 59-1
505 South Mathews Ave
Urbana, Illinois  61801
USA
;
_publ_section_title
;
 Crystal structure of a 2:1 piroxicam--gentisic acid co-crystal featuring
 neutral and zwitterionic piroxicam molecules
;
_journal_coeditor_code           HB7625
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              1714
_journal_page_last               1717
_journal_paper_doi               10.1107/S2056989016017321
_journal_volume                  72
_journal_year                    2016
_chemical_formula_iupac          '2C15 H13 N3 O4 S, C7 H6 O4'
_chemical_formula_moiety         '2(C15 H13 N3 O4 S), C7 H6 O4'
_chemical_formula_sum            'C37 H32 N6 O12 S2'
_chemical_formula_weight         816.80
_chemical_name_common
;
Piroxicam--gentisic acid (2/1)
;
_chemical_name_systematic
'4-Hydroxy-1,1-dioxo-<i>N</i>-(pyridin-2-yl)-2<i>H</i>-1\l^6^,2-benzothiazine-3-carboxamide--2-(4-oxido-1,1-dioxo-2<i>H</i>-1\l^6^,2-benzothiazine-3-amido)pyridin-1-ium--2,5-dihydroxybenzoic acid'
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2014/6
_cell_angle_alpha                80.4660(15)
_cell_angle_beta                 85.4332(15)
_cell_angle_gamma                78.4602(15)
_cell_formula_units_Z            2
_cell_length_a                   8.8764(3)
_cell_length_b                   13.4060(5)
_cell_length_c                   15.2678(6)
_cell_measurement_reflns_used    9375
_cell_measurement_temperature    105(2)
_cell_measurement_theta_max      68.14
_cell_measurement_theta_min      2.94
_cell_volume                     1753.48(11)
_computing_cell_refinement
;
SAINT (Bruker, 2014)
;
_computing_data_collection
;
APEX2 (Bruker, 2014)
;
_computing_data_reduction
;
SAINT  (Bruker, 2014) and XPREP  (Bruker, 2014)
;
_computing_molecular_graphics
;
SHELXTL (Sheldrick, 2008), CrystalMaker (CrystalMaker, 1994)
;
_computing_publication_material
;
<i>XCIF</i> (Bruker, 2014)
;
_computing_structure_refinement
;
<i>SHELXL2014-6</i> (Sheldrick, 2015)
;
_computing_structure_solution
;
<i>SHELXS2014-4</i> (Sheldrick, 2008)
;
_diffrn_ambient_temperature      105(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       'Bruker D8 Venture/Photon 100'
_diffrn_measurement_method       'profile data from \f and \w scans'
_diffrn_radiation_monochromator  'multilayer mirrors'
_diffrn_radiation_source         'microfocus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0365
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            49307
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.252
_diffrn_reflns_theta_min         2.938
_exptl_absorpt_coefficient_mu    2.050
_exptl_absorpt_correction_T_max  0.96539
_exptl_absorpt_correction_T_min  0.86702
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details
;
(SADABS; Bruker, 2014)
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.547
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.151
_exptl_crystal_size_mid          0.151
_exptl_crystal_size_min          0.028
_refine_diff_density_max         0.243
_refine_diff_density_min         -0.397
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.110
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     637
_refine_ls_number_reflns         6416
_refine_ls_number_restraints     374
_refine_ls_restrained_S_all      1.080
_refine_ls_R_factor_all          0.0384
_refine_ls_R_factor_gt           0.0334
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0348P)^2^+1.2991P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0836
_refine_ls_wR_factor_ref         0.0860
_reflns_number_gt                5801
_reflns_number_total             6416
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            hb7625sup1.cif
_cod_data_source_block           I
_cod_database_code               2241932
_cod_database_fobs_code          2241932
_shelx_estimated_absorpt_t_min   0.747
_shelx_estimated_absorpt_t_max   0.945
_shelx_hkl_checksum              51495
_shelx_res_checksum              51730
_shelxl_version_number           2014/6