It was never marketed for medical use due to safety problems but is currently used inscientific research.
Some of the safety liabilities that led to its discontinuation for the treatment of insomnia has led to its potential repurposing in the field ofoncology. Specifically, ritanserin acts as a potent inhibitor of diacylglycerol kinase alpha (DGKα). As such, it may be used to treat certain types ofglioblastoma[6][7] andmelanoma. It has also been used as a reference compound to identify putatively more selective and potent DGKα inhibitors to treat these forms of cancer as well as possibly others.[8]
Ritanserin is thegeneric name of the drug and itsINNTooltip International Nonproprietary Name,USANTooltip United States Adopted Name, andBANTooltip British Approved Name.[2][1] It is also known by its developmental code nameR-55667.[1]
Aminothiazole (2-thiazolamine) (1) is condensed with 2-acetylbutyrolactone [517-23-7] (2) under DS-trap until the water has separated. Condensation of this β-keto lactone can be visualized to involve initial attack on the reactive butyrolactone by the primary nitrogen; cyclodehydration of that hypothetical intermediate 3 gives 6-(2-hydroxyethyl)-7-methyl-[1,3]thiazolo[3,2-a]pyrimidin-5-one,CID:82612453 (4). Halogenation of the terminal alcohol with phosphorus oxychloride then yields 6-(2-chloroethyl)- 7-methyl-5H-thiazolo[3,2-a]pyrimidin-5-one, [86488-00-8] (5). Alkylation with 4-(bis(4-fluorophenyl)methylene)piperidine, [58113-36-3] (6) would complete the synthesis of ritanserin (7).
^Paiva T, Arriaga F, Wauquier A, Lara E, Largo R, Leitao JN (1988). "Effects of ritanserin on sleep disturbances of dysthymic patients".Psychopharmacology.96 (3):395–9.doi:10.1007/BF00216069.PMID3146774.S2CID19232592.
^abAkhondzadeh S, Malek-Hosseini M, Ghoreishi A, Raznahan M, Rezazadeh SA (December 2008). "Effect of ritanserin, a 5HT2A/2C antagonist, on negative symptoms of schizophrenia: a double-blind randomized placebo-controlled study".Progress in Neuro-Psychopharmacology & Biological Psychiatry.32 (8):1879–1883.doi:10.1016/j.pnpbp.2008.08.020.PMID18801405.S2CID12270281.
^abcLeysen JE, Gommeren W, Van Gompel P, Wynants J, Janssen PF, Laduron PM (June 1985). "Receptor-binding properties in vitro and in vivo of ritanserin: A very potent and long acting serotonin-S2 antagonist".Molecular Pharmacology.27 (6):600–611.doi:10.1016/S0026-895X(25)12558-3.PMID2860558.
^Nappi G, Sandrini G, Granella F, Ruiz L, Cerutti G, Facchinetti F, et al. (June 1990). "A new 5-HT2 antagonist (ritanserin) in the treatment of chronic headache with depression. A double-blind study vs amitriptyline".Headache.30 (7):439–444.doi:10.1111/j.1526-4610.1990.hed3007439.x.hdl:11380/740716.PMID2119355.S2CID25781431.