Spiroperidol - Spiperone

The synthesis of fluorine-18-labelled receptor-based radiopharmaceuticals carried out before 1986 have been reviewed331 and the methods applied for the synthesis of 18F-butyrophenone neuroleptics such as spiroperidol (spiperone), haloperidol have been critically evaluated. The synthesis for preparing 7V-(2-[18F]fluoroethyl)spiperone330 involving the [18F]fluoride ion displacement of a suitable leaving group on the ethyl side chain was found to be particularly good (>50% yield). 

Figure 11.5. Correlation between the average daily dose of various neuroleptics and their affinity for D2 receptors. (l)=promazine (2)=chlorpromazine (3)=thio-ridazine (4)=clozapine (5)=triflupromazine (6)=penfluridol (7)=trifluoperazine (8)=fluphenazine (9)=haloperidol (10)=pimozide (ll)=fluspirilene (12)=benper-idol (13)=spiroperidol (spiperone).

Fluoride sources other than hydrogen fluoride, such as tetrabutylammonium fluoride (TBAF) or cesium fluoride in the presence of acids (methanesulfonic acid, trifluoroacctic acid or cation-exchange resins), have been used for the aromatic fluorination of aryltriazenes (see Table Thus, no-carrier-added l F]fluorine-labeled pharmaceuticals, such as spiroperidol. spiperone-" (Table 4, entries 7 and 9). and haloperidol- (entry 8). are available in high radiochemical yield. 

Haloperidol was introduced for the treatment of psychoses in Europe in 1958 and in the United States in 1967 (Fig. 22.7). it is an effective aiternative to more famiiiar antipsychotic phenothiazine drugs and also is used for the manic phase of bipolar (manic-depressive) disorder. Haloperidol decanoate has been introduced as depot maintenance therapy. When injected every 4 to 6 weeks, the drug appears to be as effective as daily orally administered haloperidol. Other currently available (mostly in Europe) butyrophenones include the very potent spiperone (spiroperidol) as well as trifluperidol and droperidol. Droperidol, a short-acting, sedating butyrophenone, is used in anesthesia for its sedating and antiemetic effects and, sometimes, in psychiatric emergencies as a sedative-neuroleptic. Droperidol often is administered in combination with the potent narcotic analgesic fentanyl for preanesthetic sedation and anesthesia. 

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