1,3,7-Trimethyl-2,4-dioxo-1,2,3,4-tetrahydropteridine-6-carboxylic acid hemihydrate
Faure, René; Illán-Cabeza, Nuria A.; Jiménez-Pulido, Sonia B.; Linares-Ordóñez, Fátima M.; Moreno-Carretero, Miguel N.; Acta Crystallographica Section E 66 (2010) o719–o720; doi:10.1107/S1600536810007166

data_2225160
_publ_section_title
;
 1,3,7-Trimethyl-2,4-dioxo-1,2,3,4-tetrahydropteridine-6-carboxylic
 acid hemihydrate
;
_journal_coeditor_code           BG2332
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o719
_journal_page_last               o720
_journal_paper_doi               10.1107/S1600536810007166
_journal_volume                  66
_journal_year                    2010
_chemical_formula_iupac          'C10 H10 N4 O4, 0.5H2 O'
_chemical_formula_moiety         'C10 H10 N4 O4, 0.5(H2 O)'
_chemical_formula_sum            'C10 H11 N4 O4.5'
_chemical_formula_weight         259.23
_chemical_name_systematic
;
1,3,7-Trimethyl-2,4-dioxo-1,2,3,4-tetrahydropteridine-6-carboxylic acid
hemihydrate
;
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/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                 106.113(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   15.7328(19)
_cell_length_b                   11.5784(16)
_cell_length_c                   12.4062(18)
_cell_measurement_reflns_used    1970
_cell_measurement_temperature    120(2)
_cell_measurement_theta_max      25.25
_cell_measurement_theta_min      2.22
_cell_volume                     2171.1(5)
_computing_cell_refinement       'DIRAX/LSQ (Duisenberg, 1992)'
_computing_data_collection       'COLLECT (Nonius, 1998)'
_computing_data_reduction        'EvalCCD (Duisenberg <i>et al.</i>,  2003)'
_computing_molecular_graphics    'Mercury (Macrae <i>et al.</i>,  2006)'
_computing_publication_material
'WinGX (Farrugia, 1999) and PLATON (Spek, 2009)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXL97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      120(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       'CCD rotation images, thick slices'
_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  0.0383
_diffrn_reflns_av_sigmaI/netI    0.0248
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            14172
_diffrn_reflns_theta_full        25.25
_diffrn_reflns_theta_max         25.25
_diffrn_reflns_theta_min         2.22
_exptl_absorpt_coefficient_mu    0.128
_exptl_absorpt_correction_T_max  0.9761
_exptl_absorpt_correction_T_min  0.9436
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 2003)'
_exptl_crystal_colour            'light yellow'
_exptl_crystal_density_diffrn    1.586
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1080
_exptl_crystal_size_max          0.46
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.19
_refine_diff_density_max         0.651
_refine_diff_density_min         -0.576
_refine_ls_extinction_coef       0.0125(14)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL97 (Sheldrick, 2008)'
_refine_ls_goodness_of_fit_ref   1.207
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     180
_refine_ls_number_reflns         1970
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.207
_refine_ls_R_factor_all          0.0753
_refine_ls_R_factor_gt           0.0551
_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^)+(0.0794P)^2^+0.6244P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1240
_refine_ls_wR_factor_ref         0.1402
_reflns_number_gt                1493
_reflns_number_total             1970
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            bg2332.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               2225160
_cod_database_fobs_code          2225160