2,4-dithiouracil: the reproducible H-bonded structural motifs in the complexes with 18-membered crown ethers.
Wang, Wen-Jwu; Ganin, Eduard V.; Fonari, Marina S.; Simonov, Yurii A.; Bocelli, Gabriele; Organic & biomolecular chemistry 3 (2005) 3054–3058; doi:10.1039/b505807d

data_7150192
_publ_section_title
;
 2,4-dithiouracil: the reproducible H-bonded structural motifs in the
 complexes with 18-membered crown ethers.
;
_journal_issue                   16
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3054
_journal_page_last               3058
_journal_paper_doi               10.1039/b505807d
_journal_volume                  3
_journal_year                    2005
_chemical_formula_moiety         'C12 H24 O6, C4 H4 N2 S2, H2 O'
_chemical_formula_sum            'C16 H30 N2 O7 S2'
_chemical_formula_weight         426.54
_chemical_melting_point          265
_chemical_name_common
;
1,4,7,10,13,16-hexaoxacyclooctadecane pyrimidine-2,4(1H,3H)-
dithione monohydrate
;
_chemical_name_systematic
;
1,4,7,10,13,16-hexaoxacyclooctadecane
pyrimidine-2,4(1H,3H)-dithione monohydrate
;
_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                 92.17(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.7070(15)
_cell_length_b                   17.374(4)
_cell_length_c                   16.622(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      17.90
_cell_measurement_theta_min      13.22
_cell_volume                     2224.1(8)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Philips Pw100'
_diffrn_measurement_method       'omega-2theta 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  0.0173
_diffrn_reflns_av_sigmaI/netI    0.0217
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       0
_diffrn_reflns_number            4524
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         3.10
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 100
_diffrn_standards_number         1
_exptl_absorpt_coefficient_mu    0.276
_exptl_absorpt_correction_T_max  0.9444
_exptl_absorpt_correction_T_min  0.9121
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.274
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             912
_exptl_crystal_size_max          0.34
_exptl_crystal_size_mid          0.27
_exptl_crystal_size_min          0.21
_refine_diff_density_max         0.432
_refine_diff_density_min         -0.278
_refine_diff_density_rms         0.051
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.088
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     256
_refine_ls_number_reflns         4380
_refine_ls_number_restraints     5
_refine_ls_restrained_S_all      1.089
_refine_ls_R_factor_all          0.0667
_refine_ls_R_factor_gt           0.0452
_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^)+(0.0719P)^2^+0.2350P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1237
_refine_ls_wR_factor_ref         0.1320
_reflns_number_gt                3152
_reflns_number_total             4380
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b505807d.txt
_cod_data_source_block           dtu1
_cod_original_sg_symbol_H-M      P21/n
_cod_database_code               7150192