The Acid and/or Thermal Mediated Ring Contraction of 4H-1,2,6-Thiadiazines To Afford 1,2,5-Thiadiazoles.
Kalogirou, Andreas S.; Kourtellaris, Andreas; Koutentis, Panayiotis A.; Organic letters 18 (2016) 4056–4059; doi:10.1021/acs.orglett.6b01929

data_1543768
_publ_section_title
;
 The Acid and/or Thermal Mediated Ring Contraction of
 4H-1,2,6-Thiadiazines To Afford 1,2,5-Thiadiazoles.
;
_journal_issue                   16
_journal_name_full               'Organic letters'
_journal_page_first              4056
_journal_page_last               4059
_journal_paper_doi               10.1021/acs.orglett.6b01929
_journal_volume                  18
_journal_year                    2016
_chemical_formula_moiety         'C21 H12 N4 O6 S'
_chemical_formula_sum            'C21 H12 N4 O6 S'
_chemical_formula_weight         448.41
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 93.738(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   7.9088(2)
_cell_length_b                   13.4071(4)
_cell_length_c                   9.2050(3)
_cell_measurement_reflns_used    4299
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      72.1780
_cell_measurement_theta_min      5.5940
_cell_volume                     973.97(5)
_computing_cell_refinement       'CrysAlis RED'
_computing_data_collection       'CrysAlis CCD'
_computing_data_reduction        'CrysAlis RED'
_computing_molecular_graphics
;
 DIAMOND (Brandenburg, 2006)
 MERCURY (Bruno et al. 2002)
;
_computing_publication_material  'WINGX (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXL-97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 10.4223
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, Atlas'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_source         'SuperNova (Cu) X-ray Source'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0189
_diffrn_reflns_av_sigmaI/netI    0.0248
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            5743
_diffrn_reflns_theta_full        67.00
_diffrn_reflns_theta_max         67.00
_diffrn_reflns_theta_min         5.61
_exptl_absorpt_coefficient_mu    1.927
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.83602
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'Empirical absorption correction (CrysAlis RED, Oxford Diffraction)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.529
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       Polyhedral
_exptl_crystal_F_000             460
_exptl_crystal_size_max          0.08
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.199
_refine_diff_density_min         -0.278
_refine_diff_density_rms         0.048
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.95(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.025
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     289
_refine_ls_number_reflns         2975
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.025
_refine_ls_R_factor_all          0.0427
_refine_ls_R_factor_gt           0.0420
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0576P)^2^+1.2642P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1065
_refine_ls_wR_factor_ref         0.1071
_reflns_number_gt                2916
_reflns_number_total             2975
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol6b01929_si_002.cif
_cod_data_source_block           shelxl
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to
/usr/data/users/saulius/crontab/automatic-downloads/rss-feeds/ACS/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 from 2011-04-26.

Automatic conversion script
Id: cif_fix_values 4268 2015-11-12 08:31:59Z antanas 

 Adding full bibliography for 1543767--1543769.cif.
;
_cod_original_sg_symbol_Hall     '-P 2yb'
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               1543768