2-Methyl-7-oxo-5,6,7,8-tetrahydropyrimido[4,5-<i>d</i>]pyrimidin-3-ium chloride, a product of the thermal decomposition of nimustine hydrochloride (ACNU)
Chernyshev, Ilya V.; Tursina, Anna I.; Acta Crystallographica Section E 61 (2005) o544–o546; doi:10.1107/S1600536805002874

data_2205235
_publ_section_title
;
 2-Methyl-7-oxo-5,6,7,8-tetrahydropyrimido[4,5-<i>d</i>]pyrimidin-3-ium
 chloride, a product of the thermal decomposition of nimustine
 hydrochloride (ACNU)
;
_journal_issue                   3
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o544
_journal_page_last               o546
_journal_paper_doi               10.1107/S1600536805002874
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C7 H9 N4 O +, Cl -'
_chemical_formula_moiety         'C7 H9 N4 O +, Cl -'
_chemical_formula_sum            'C7 H9 Cl N4 O'
_chemical_formula_weight         200.63
_chemical_name_systematic
;
2-Methyl-7-oxo-5,6,7,8-tetrahydropyrimido[4,5-d]pyrimidin-3-ium chloride
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                105.60(7)
_cell_angle_beta                 91.87(7)
_cell_angle_gamma                102.17(7)
_cell_formula_units_Z            2
_cell_length_a                   4.877(3)
_cell_length_b                   8.104(6)
_cell_length_c                   11.832(7)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      8.63
_cell_measurement_theta_min      5.28
_cell_volume                     438.3(5)
_computing_cell_refinement       'CAD-4 EXPRESS'
_computing_data_collection       'CAD-4 EXPRESS (Enraf--Nonius, 1994)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_molecular_graphics
;
DIAMOND (Branderburg, 1998) and ORTEP-3 (Farrugia, 1997)
;
_computing_publication_material
;
WinGX (Farrugia, 1999)
;
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Enraf--Nonius CAD-4'
_diffrn_measurement_method       \w
_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  0.0978
_diffrn_reflns_av_sigmaI/netI    0.1374
_diffrn_reflns_limit_h_max       4
_diffrn_reflns_limit_h_min       -4
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            1639
_diffrn_reflns_theta_full        19.97
_diffrn_reflns_theta_max         19.97
_diffrn_reflns_theta_min         1.80
_diffrn_standards_decay_%        2
_diffrn_standards_interval_time  120
_diffrn_standards_number         1
_exptl_absorpt_coefficient_mu    0.399
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.520
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Prism
_exptl_crystal_F_000             208
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.06
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.241
_refine_diff_density_min         -0.198
_refine_ls_extinction_coef       0.0040(10)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL97
_refine_ls_goodness_of_fit_ref   0.969
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     120
_refine_ls_number_reflns         821
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.969
_refine_ls_R_factor_all          0.1478
_refine_ls_R_factor_gt           0.0376
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w = 1/[\s^2^(Fo^2^)+(0.0243P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0662
_refine_ls_wR_factor_ref         0.0863
_reflns_number_gt                421
_reflns_number_total             821
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ci6518.cif
_cod_data_source_block           II
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Triclinic' changed to 'triclinic'
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_database_code               2205235
_cod_database_fobs_code          2205235