Tizanidine and tizanidine hydrochloride: on the correct tautomeric form of tizanidine
Bekö, Sándor L.; Thoms, Silke D.; Schmidt, Martin U.; Bolte, Michael; Acta Crystallographica Section C 68 (2012) o28–o32; doi:10.1107/S0108270111052012

data_2018357
_publ_section_title
;
 Tizanidine and tizanidine hydrochloride: on the correct tautomeric form
 of tizanidine
;
_journal_coeditor_code           SK3425
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o28
_journal_page_last               o32
_journal_paper_doi               10.1107/S0108270111052012
_journal_volume                  68
_journal_year                    2012
_chemical_formula_iupac          'C9 H9 Cl N5 S +, Cl -'
_chemical_formula_moiety         'C9 H9 Cl N5 S +, Cl -'
_chemical_formula_sum            'C9 H9 Cl2 N5 S'
_chemical_formula_weight         290.17
_chemical_name_common            'Tizanidine hydrochloride'
_chemical_name_systematic
;
2-[(5-chloro-2,1,3-benzothiadiazol-4-yl)amino]imidazolidinium chloride
;
_space_group_IT_number           14
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;
SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and
<i>publCIF</i> (Westrip,
2010)
;
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_exptl_crystal_description       block
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_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
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_refine_ls_number_reflns         2383
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.979
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_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^)+(0.0451P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_threshold_expression     I>2\s(I)
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