{{Short description|Organic compound}} {{chembox | verifiedrevid = 425007809 | Name = 1,4-Thiazine | ImageFile = | ImageFile1 = 4H-1,4-thiazine with Atom Numbers.svg | ImageSize1 = 100px | PIN = 4''H''-1,4-Thiazine | OtherNames = Parathiazine | Section1 = {{Chembox Identifiers | index2_label = 1,2 | index3_label = 1,3 | index4_label = 1,4 | CASNo=290-57-3 | CASNo2=11084-06-3 | CASNo3 = 27813-20-3 | PubChem2=15789245 | PubChem3 = 15789246 | PubChem4 = 15789247 | ChemSpiderID2 = 10609054 | ChemSpiderID3 = 10609007 | ChemSpiderID4 = 10465777 | DTXSID2 = DTXSID50911874 | DTXSID3 = DTXSID50578325 | SMILES2 = C1=CNSC=C1 | SMILES3 = C1N=CC=CS1 | SMILES4 = C\1=C\N\C=C/S/1 | InChI4 = 1S/C4H5NS/c1-3-6-4-2-5-1/h1-5H | InChIKey4 = ZOXMLSDKXHNVOQ-UHFFFAOYSA-N | InChI2=1S/C4H5NS/c1-2-4-6-5-3-1/h1-5H | InChIKey2=AGIJRRREJXSQJR-UHFFFAOYSA-N | InChI3=1S/C4H5NS/c1-2-5-4-6-3-1/h1-3H,4H2 | InChIKey3 = NTYABNDBNKVWOO-UHFFFAOYSA-N }} | Section2 = {{Chembox Properties | Formula= | C=4 | H=5 | N=1 | S=1 | MolarMass= | Appearance= | Density=0.8465 g/cm<sup>3</sup> | MeltingPt= | BoilingPt=76.5 °C | Solubility= | pKa = | pKb = }} | Section3 = {{Chembox Hazards | MainHazards= | FlashPt= | AutoignitionPt = }} | Section4 = | Section5 = | Section6 = | Section8 = {{Chembox Related | OtherCompounds = }} }}
'''Thiazine''' {{IPAc-en|ˈ|θ|aɪ|ə|z|iː|n}} is an organic compound containing a ring of four carbon, one nitrogen and one sulfur atom. There are three isomers of thiazine, 1,2-thiazine, 1,3-thiazine, and 1,4-thiazine, which differ by the arrangement of the nitrogen and sulfur atoms in the ring.
Derivatives of thiazine, often referred to as thiazines, are used for dyes, tranquilizers and insecticides.
== Preparation == 1,4-thiazine can be prepared from the corresponding dione using aluminium powder at high temperature.<ref>{{Cite journal|last1=Barkenbus|first1=Charles|last2=Landis|first2=Phillip S.|date=February 1948|title=The Preparation of 1,4-Thiazine|journal=Journal of the American Chemical Society|volume=70|issue=2|pages=684–685|doi=10.1021/ja01182a075|bibcode=1948JAChS..70..684B |issn=0002-7863}}</ref> center|frameless|Synthesis of 1,4-thiazine.
== Tautomers == center|frameless Three tautomers of 1,4-thiazine exist as above.
==See also== *Methylene blue, contains a related ring with nitrogen and a positively charged sulfur atom *Phenothiazine, a thiazine fused with two benzene rings *Thiomorpholine, a saturated analog of thiazine
== References == <references />
Category:Thiazines