4H-1,4-Thiazine 1,1-dioxides

B. 4H-1,4 -Thiazine 1,1-Dioxide. Caution This step should he carried out in a hood to avoid exposure to hydrogen chloride gas. 

Ozone/sulfur dioxide 4H-1,4-Thiazine 1,1-dioxides from 2,5-dihydrothiophene 1,1-dioxides via 2,6-dialkoxy-l,4-oxathiane 4,4-dioxides... 

Dihydrothiophene 1,1-dioxide treated with ozone in abs. ethanol and methylene chloride wtih Dry Ice-methanol cooling and stirring until the soln. becomes blue, treated portionwise with liq. SOg during 10-15 sec., and after 2 min. allowed to warm to room temp, during 8-16 hrs. cis- and trfl -2,6-diethoxy-l,4-oxa-thiane 4,4-dioxide (Y 74-81%) mixed with NH4CI and glacial acetic acid, placed in an oil bath preheated to 125-130°, stirred and refluxed 25-35 min. 4H-1,4-thiazine 1,1-dioxide (Y 69-83%). - By the above ozonolysis process, acetals can be obtained from ethylene derivs. E l-Chloro-4-(o-nitrophenyl)-2-butene and methanol -> o-nitrophenylacetaldehyde dimethyl acetal. Y 84%. F. e. s. W. E. Noland and R. D. DeMaster, Org. Synth. 52, 135 (1972). 

Das Sulfon I wird nur bis zur Hydroxylamin-Stufe hydriert durch nachfolgende Kon-densation erhalt man 4-Hydroxy-3-phenyl-4H- benzo-1,4-thiazin)-1,1 -dioxid, das bei verlaingerter Hydrierzeit hydrogcnolytisch gespalten wird6 ... 

Dicyanomethylenediphenylcyclopropene and an equimolar amount of mesoionic 3-methyl-2,4-diphenylthiazol-5-one refluxed 8 hrs. in xylene -> product. Y 74%. F. e. s. H. Matsukubo and H. Kato, Soc. Perkin I 1975, 632 4H-l,4-thiazine 1,1-dioxides by cycloaddition-extrusion-ring expansion s. Chem. Lett. 1975, 1153. 

A mixture of phenacyl sulfone and urea refluxed 18hrs. in glacial acetic acid 3,5-diphenyl-4H-l,4-thiazine 1,1-dioxide. Y 90%. F. e. s. G. R. Johnson and I. Sataty, J. Med. Ghem. 10, 501 (1967). 

Chemical Name 2-(4-Chlorophenyl)tetrahydro-3-methyl-4H-1,3-thiazin-4-one 1,1-dioxide Common Name Chloromethazanone Structural Formula ... 

The protons at positions 2 and 6 of symmetrical thiazine dioxides resonate in the 5 5.95-6.36 region in the case of the anion 48, the protons are shifted upheld by 0.45 ppm (to 5 5.91). The parent compound 40 provides the only example of a 4H-l,4-thiazine dioxide, unsubstituted at positions 3 and 5, whose NMR spectrum has been reported the 3- and 5-protons appear as a multiplet centered at S 1.06f ... 

A soln. of 6-phenyl-2,3,4,7-tetrahydro-l,4,5-thiadiazepin-3-one 1,1-dioxide in acetic anhydride refluxed 6 hr. 4-(diacetylamino)-2,3-dihydro-5-phenyl-4H-l,4-thiazin-3-one 1,1-dioxide. Y 50%. I. Sataty, Tetrahedron 28, 2307 (1972). 

E)-6-chloro-3-[hydroxy(pyridine-2-ylamino)methylene]-2-methyl-2,3-dihydro-4H-thieno [2,3-e] [1,2] thiazin-4-one, 1,1 -dioxide. 

C5H6N2O2S, 4-Carboxylato-L-thiazolidinehydantoin, 46B, 391 C5H6N2O3S, 2-Amino-4-thiazolidinone-5-acetic acid, 38B, 386 CsH7NOS2r 3-Methyl-4-oxo-1,3-thiazine-2-thione, 38B, 386 C5H7N5O2S, 7-Amino-3-methyl-4H-imidazo[2,3-c](1,2,6)thiadiazine 5,5-dioxide, 43B, 471... 

C8H6N2OS, 4-Phenyl-1,2,3-thiadiazole 3-oxide, 44B, 355 CbHsN20i,S2 r cis-syri cis-Tetrahydrocyclobuta[ 1,2-e 4,3-e ]bis( 1,3)-thiazine-2,4,5,7-(3H,6H)-tetrone, 37B, 203 C8H7CIN2O2S, 7-Chloro-3-methyl-4H-l,2,4-benzothiadiazine-1,1-dioxide, 43B, 474... 

Cl 2H18CI4CUN4OS, Thiamine tetrachlorocuprate, 40B, 553 Cl2H18N2O3S, 2,3-Dihydro-2-acetyl-3,3-dimethyl-4 [(lE)-4-methyl-1,3-pentadienyll l,2,5-thiadiazole 1,1-dioxide, 46B, 403 C12H18N4O3S, 2,7-Dimethylthiachromine-8-ethanol dihydrate, 40B, 350 Cl2H19N2O4PS, N-(2,6-Dimethylphenyl)-2-amino-5,6-dihydro-4H-1,3-thiazine phosphate, 45B, 429... 

C13H17N3O3S, 3-Dimethylamino-4,4-dimethyl-5,6-dihydro-4H-1,2,5-ben-zothiadiazocin-6-one-1,1-dioxide, 43B, 483 C13H18N2O2S, 2-(N-2,6-Dimethylphenyl-N-mesyl-amino)-dihydro-1,3-thiazine, 43B, 484... 

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