Oxidation of 5,6-Diamino-1,3-dimethyluracil by Metal Ions: Structure of 1,3,6,8-Tetramethyl-2,4,7,9(1<i>H</i>,3<i>H</i>,6<i>H</i>,8<i>H</i>)-pyrimido[4,5-<i>g</i>]pteridinetetrone
Romerosa, A.; Colacio, E.; Suárez-Varela, J.; Avila-Rosón, J. C.; Hidalgo, M. A.; Romero-Garzón, J.; Acta Crystallographica Section C 51 (1995) 1005–1007; doi:10.1107/S0108270194009595

data_2003478
_publ_section_title
;Oxidation of 5,6-Diamino-1,3-dimethyluracil by Metal Ions: Structure of
 1,3,6,8-Tetramethyl-2,4,7,9(1<i>H</i>,3<i>H</i>,6<i>H</i>,8<i>H</i>)-pyrimido[4,5-<i>g</i>]pteridinetetrone
;
_journal_issue                   5
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1005
_journal_page_last               1007
_journal_paper_doi               10.1107/S0108270194009595
_journal_volume                  51
_journal_year                    1995
_chemical_formula_sum            'C12 H12 N6 O4'
_chemical_formula_weight         304.3
_chemical_name_systematic
;
1,3,5,7-tetramethyl-2,4,6,8(1H,3H,5H,7H)-pyrimido[4,5-g]pteridinetetrone
;
_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_type_scat_source           'IntTabIV, Tables 2.2B and 2.3.1'
_cell_angle_alpha                90.0
_cell_angle_beta                 105.98(3)
_cell_angle_gamma                90.0
_cell_formula_units_Z            4
_cell_length_a                   15.750(3)
_cell_length_b                   6.112(2)
_cell_length_c                   13.704(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293
_cell_measurement_theta_max      17.5
_cell_measurement_theta_min      12.5
_cell_volume                     1268.2(6)
_computing_cell_refinement       'DIF4 Control program vers. 7 (STOE & CIE)'
_computing_data_collection       'DIF4 Control program vers. 7 (STOE & CIE)'
_computing_data_reduction        'REDU4 program (STOE & CIE)'
_computing_molecular_graphics    'SHELXTL PLUS package (Sheldrick, NICOLET)'
_computing_structure_refinement  'SHELXTL PLUS package (Sheldrick, NICOLET)'
_computing_structure_solution    'SHELXTL PLUS package (Sheldrick, NICOLET)'
_diffrn_ambient_temperature      293
_diffrn_measurement_device       'Stoe-Siemens AED 2 diffractometer'
_diffrn_measurement_method       \w/2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'X-ray tube'
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71069
_diffrn_reflns_av_R_equivalents  0.0601
_diffrn_reflns_av_sigmaI/netI    0.1636
_diffrn_reflns_limit_h_max       23
_diffrn_reflns_limit_h_min       -2
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -2
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            3680
_diffrn_reflns_reduction_process 'REDU4 program (STOE & CIE)'
_diffrn_reflns_theta_max         32.5
_diffrn_reflns_theta_min         1.5
_diffrn_standards_decay_%        2
_diffrn_standards_interval_time  90
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.12
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            'Pale yellow'
_exptl_crystal_density_diffrn    1.594
_exptl_crystal_description       Prism
_exptl_crystal_F_000             632
_exptl_crystal_size_max          0.5
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.37
_refine_diff_density_min         -0.36
_refine_ls_goodness_of_fit_obs   2.3091
_refine_ls_hydrogen_treatment    refU
_refine_ls_matrix_type           full
_refine_ls_number_parameters     112
_refine_ls_number_reflns         794
_refine_ls_R_factor_all          0.2251
_refine_ls_R_factor_obs          0.0482
_refine_ls_shift/esd_max         0.324
_refine_ls_shift/esd_mean        0.037
_refine_ls_structure_factor_coef F
_refine_ls_weighting_scheme      unit
_refine_ls_wR_factor_all         0.1690
_refine_ls_wR_factor_obs         0.0526
_reflns_number_observed          794
_reflns_number_total             3468
_reflns_observed_criterion       refl_observed_if_F_>_6.0_sigma(F)
_cod_data_source_file            mu1130.cif
_cod_data_source_block           ugr_pira
_cod_original_sg_symbol_H-M      C2/c
_cod_database_code               2003478