Fluspidine

Fluspidine

File:Fluspidine.svg
Clinical data
Other names	[18F]-Fluspidine
Identifiers
IUPAC name 1'-benzyl-1-(2-(17F)fluoranylethyl)spiro[1H-2-benzofuran-3,4'-piperidine]
CAS Number	1355357-60-6
PubChem CID	71719166
ChemSpider	29397143
ChEMBL	ChEMBL1939706
E number	{{#property:P628}}
CompTox Dashboard (EPA)	{{#property:P3117}}
ECHA InfoCard	{{#property:P2566}}
Chemical and physical data
Formula	C21H24FNO
Molar mass	325.427 g·mol−1
3D model (JSmol)	Interactive image
SMILES C1CN(CCC12C3=CC=CC=C3C(O2)CC[18F])CC4=CC=CC=C4
InChI InChI=InChI=1S/C21H24FNO/c22-13-10-20-18-8-4-5-9-19(18)21(24-20)11-14-23(15-12-21)16-17-6-2-1-3-7-17/h1-9,20H,10-16H2/i22-1 Key:LDFPQKADFLEDQV-KVTPGWOSSA-N

Fluspidine is a fluorine-18 (¹⁸F) labeled radiotracer used in positron emission tomography (PET) scans to image σ₁ (sigma-1) receptors in the brain and other tissues. Sigma-1 receptors are proteins involved in many neurological and psychiatric processes. They have been linked to pain modulation, psychosis, Alzheimer's disease, and depression.

Chemical properties

Fluspidine is a small organic compound with a spirocyclic structure. A 2-fluoroethyl group on the molecule carries the fluorine-18. The compound exists as two mirror image enantiomers, called (R)-fluspidine and (S)-fluspidine. These enantiomers have slightly different properties: (R)-fluspidine has about 4-fold higher affinity for the σ₁ receptor than (S)-fluspidine, but (S)-fluspidine is metabolically more stable in the body.