The 1:1 adduct of caffeine and 2-(1,3-dioxoisoindolin-2-yl)acetic acid
Bhatti, Moazzam H.; Yunus, Uzma; Saeed, Sohail; Shah, Syed Raza; Wong, Wing-Tak; Acta Crystallographica Section E 67 (2011) o2240–; doi:10.1107/S1600536811030182

data_2231464
_publ_section_title
;
 The 1:1 adduct of caffeine and 2-(1,3-dioxoisoindolin-2-yl)acetic acid
;
_journal_coeditor_code           DS2126
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o2240
_journal_paper_doi               10.1107/S1600536811030182
_journal_volume                  67
_journal_year                    2011
_chemical_formula_iupac          'C8 H10 N4 O2, C10 H7 N O4'
_chemical_formula_moiety         'C8 H10 N4 O2, C10 H7 N O4'
_chemical_formula_sum            'C18 H17 N5 O6'
_chemical_formula_weight         399.37
_chemical_name_systematic
;
2-(1,3-dioxoisoindolin-2-yl)acetic acid--
1,3,7-trimethyl-1,2,3,6-tetrahydro-7<i>H</i>-purine-2,6-dione (1/1)
;
_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                 101.408(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   14.6595(5)
_cell_length_b                   4.6567(2)
_cell_length_c                   26.5281(8)
_cell_measurement_reflns_used    2850
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      23.03
_cell_measurement_theta_min      2.85
_cell_volume                     1775.16(11)
_computing_cell_refinement       'APEX2 (Bruker, 2007)'
_computing_data_collection       'APEX2 (Bruker, 2007)'
_computing_data_reduction        'SAINT (Bruker, 2007)'
_computing_molecular_graphics    'Mercury (Macrae <i>et al.</i>, 2008)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008<i>a</i>)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008<i>a</i>)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008<i>a</i>)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEXII CCD'
_diffrn_measurement_method       '\w and \f scan'
_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  0.0454
_diffrn_reflns_av_sigmaI/netI    0.0328
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       5
_diffrn_reflns_limit_k_min       -5
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -32
_diffrn_reflns_number            20916
_diffrn_reflns_theta_full        25.68
_diffrn_reflns_theta_max         25.68
_diffrn_reflns_theta_min         1.57
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.115
_exptl_absorpt_correction_T_max  0.9886
_exptl_absorpt_correction_T_min  0.9468
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2008<i>b</i>)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.494
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             832
_exptl_crystal_size_max          0.48
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.10
_refine_diff_density_max         0.204
_refine_diff_density_min         -0.206
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.032
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     269
_refine_ls_number_reflns         3373
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.032
_refine_ls_R_factor_all          0.0737
_refine_ls_R_factor_gt           0.0442
_refine_ls_shift/su_max          0.005
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0683P)^2^+0.2661P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1115
_refine_ls_wR_factor_ref         0.1298
_reflns_number_gt                2268
_reflns_number_total             3373
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ds2126.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2231464
_cod_database_fobs_code          2231464