|Jmol-3D images||Image 1|
|Molar mass||199.27 g/mol|
yellow rhombic leaflets or
|Melting point||185 °C (365 °F; 458 K)|
|Boiling point||371 °C (700 °F; 644 K)|
|Solubility in water||0.00051 g/L (20 °C)|
|Solubility in other solvents||benzene, ether, petroleum ether, chloroform, hot acetic acid, ethanol (slightly), mineral oil (slightly)|
|Acidity (pKa)||approx 23 in DMSO|
|Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)|
Phenothiazine is an antipsychotic and antihistaminic drugs. It has the formula S(C6H4)2NH. This yellow tricyclic compound is soluble in acetic acid, benzene, and ether. The compound is related to the thiazine-class of heterocyclic compounds. Derivatives of the parent compound find wide use as drugs.
The compound was originally prepared by Bernthsen in 1883 via the reaction of diphenylamine with sulfur, but more recent syntheses rely on the cyclization of 2-substituted diphenyl sulfide. Some of the pharmaceutically significant derivatives of phenothiazine are not prepared directly from phenothiazine, although some of them are.
The synthetic dye methylene blue, containing the structure, was described in 1876. Phenothiazine itself was introduced by DuPont as an insecticide in 1935. It is sometimes used as an antihelminthic in livestock.
Many water-soluble phenothiazine derivatives, such as methylene blue, methylene green, thionine, and others, can be electropolymerized into conductive polymers used as electrocatalysts for NADH oxidation in enzymatic biosensors and biofuel cells. 
The term "phenothiazines" describes the largest of the five main classes of neuroleptic antipsychotic drugs. These drugs have antipsychotic and, often, antiemetic properties, although they may also cause severe side effects such as extrapyramidal symptoms (including akathisia and tardive dyskinesia), hyperprolactinaemia, and the rare but potentially fatal neuroleptic malignant syndrome, as well as substantial weight gain.
Phenothiazines, particularly prochlorperazine and chlorpromazine, are also used in emergency rooms to treat migraine and other intractable headaches.
Phenothiazine antipsychotics are classified into three groups that differ with respect to the substituent on nitrogen: the aliphatic compounds (bearing acyclic groups), the "piperidines" (bearing piperidine-derived groups), and the piperazine (bearing piperazine-derived substituents).
|Group||Autonomic||Example||Sedative||Extrapyramidal side effects|
|moderate||Chlorpromazine (marketed as Thorazine, Chlor-PZ, Klorazine, Promachlor, Promapar, Sonazine, Chlorprom, Chlor-Promanyl, Largactil)||strong||moderate|
|Promazine (trade name Sparine)||moderate||moderate|
|Triflupromazine (trade names Clinazine, Novaflurazine, Pentazine, Terfluzine, Triflurin, Vesprin)||strong||moderate/strong|
|Levomepromazine in Germany and methotrimeprazine in America (trade names Nozinan, Levoprome)||extremely strong||low|
|Piperidines||strong||Mesoridazine (trade name Serentil)||strong||weak|
|Thioridazine (trade names Mellaril, Novoridazine, Thioril)||strong||weak|
|Piperazines||weak||Fluphenazine (trade names Prolixin, Permitil, Modecate, Moditen)||weak/moderate||strong|
|Perphenazine (sold as Trilafon, Etrafon, Triavil, Phenazine)||weak/moderate||strong|
|Prochlorperazine (trade names Compazine, Stemetil)|
|Trifluoperazine (trade name Stelazine)||moderate||strong|
Like many commercially significant compounds, phenothiazine has numerous trade names, including AFI-Tiazin, Agrazine, Antiverm, Biverm, Dibenzothiazine, Orimon, Lethelmin, Souframine, Nemazene, Vermitin, Padophene, Fenoverm, Fentiazine, Contaverm, Fenothiazine, Phenovarm, Ieeno, ENT 38, Helmetina, Helmetine, Penthazine, XL-50, Wurm-thional, Phenegic, Phenovis, Phenoxur, and Reconox.
- Sigma-Aldrich catalog
- Gérard Taurand, "Phenothiazine and Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005.doi:10.1002/14356007.a19_387
- T. Kahl, K.-W. Schröder, F. R. Lawrence, W. J. Marshall, Hartmut Höke, Rudolf Jäckh, "Aniline" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH: Weinheim.
- History of Insecticides and Control Equipment Clemson University Pesticide Information Program.
- PTZ Technical Information Bulletin Cytec PTZ Technical Information Bulletin
- Rang; Dale et al., Pharmacology, 6th edition
- U.S. Department of Labor Occupational Safety & Health Administration Chemical Sampling Information Phenothiazine
- PAN Pesticides Database
- Hendricks, Christensen, J.B., and Kristiansen, Jette E. Sonderborg, Denmark. "Antibakterielle Eigenschaften der Phenothiazine: Eine Behandlungsoption für die Zukunft?" Chemotherapie Journal. 13.5. (2004): 203–205. Wissenschaftliche Verlagsgesesellschaft mbH. 21 August 2005. (PDF).
- PubChem Substance Summary: Phenothiazine National Center for Biotechnology Information.
- CDC - NIOSH Pocket Guide to Chemical Hazards