Table 4.
20 PET radioligands: peak brain uptakes in monkey and human, and some of their molecular properties.
| Radioliganda | Structure | Target | Peak monkey brain uptakeb [SUV] | Peak human brain uptakeb [SUV] | MWtc [Da] | LogD7.4d | cLogP | N + O | HBDse | HBAsf | PSAg [Å2] | Most basic siteh pKa |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| [11C](R)-PK11195 |
|
TSPO | 1.6 [43] | 1.6 | 353 | 3.97 | 4.89 | 3 | 0 | 3 | 33 | 3.53 |
| [11C]ER176 |
|
TSPO | 2.0 [145] | 2.3 [146] | 353 | 3.55 [145] | 3.80 | 4 | 0 | 1 | 45 | 0.2 |
| [11C]SD5024 |
|
CB1 | 2.0 [147] | 2.3 [147] | 463 | 3.79 [147] | 3.50 | 7 | 1 | 2 | 112 | 4.98 |
| [11C]IGA-1 |
|
TSPO | 2.3 [48] | n.d. | 406 | 3.35 | 7 | 0 | 3 | 92 | NA | |
| [11C]PBR28 |
|
TSPO | 2.8 [105, 148] | 2.6 [80, 42, 149, 150] | 348 | 3.01 | 2.56 | 5 | 0 | 5 | 51 | 6.58 |
| [11C]PBR01 |
|
TSPO | 3.0 [105, 151] | n.d. | 374 | 3.90 | 3.05 | 4 | 0 | 56 | 4.4 | |
| [11C]RX-1 |
|
5-HT1A | 3.5 [152] | n.d. | 321 | 1.77 | 2.36 | 5 | 1 | 3 | 65 | 8.47 |
| [18F]FBR |
|
TSPO | 3.7 [106] | 1.3 [150, 153] | 395 | 4.05 | 3.58 | 5 | 0 | 5 | 48 | 4.99 |
| [11C]RWAY |
|
5-HT1A | 4.2 [127, 154, 155] | 2.2 [156] | 436 | 3.16 | 2.85 | 5 | 0 | 5 | 36 | 7.94 |
| [11C](R)-rolipram |
|
PDE4 | 4.3 | 2.3 [157, 158] | 275 | 2.16 | 2.35 | 4 | 1 | 3 | 48 | 7.61 |
| [18F]RX-2 |
|
5-HT4 | 4.31 [152] | n.d. | 289 | 1.54 [152] | 1.42 | 4 | 1 | 3 | 56 | 8.47 |
| [18F]XB-1 |
|
H3 | 4.5 [159] | n.d. | 351 | 2.95 | 4.34 | 3 | 0 | 3 | 30 | 9.29 |
| [11C]NOP-1A |
|
NOP | 4.9 [160, 161] | 6.2 [162, 163] | 408 | 3.41 | 3.47 | 4 | 1 | 3 | 42 | 7.36 |
| [18F]FIMX |
|
mGlu1 | 5.3 [107] | 4.8 | 343 | 2.52 [107] | 0.69 | 7 | 1 | 3 | 69 | 4.95 |
| [18F]FMPEP-d2 |
|
CB1 | 5.5 [140] | 4.8 [140] | 473 | 4.24 | 4.99 | 4 | 1 | 3 | 42 | 6.86 |
| [11C]MePPEP |
|
CB1 | 6.0 [164] | 4.0 [164] | 455 | 4.80 | 4.87 | 4 | 1 | 3 | 42 | 6.86 |
| [11C]CUMI-101 |
|
5-HT1A | ~ 6 [155] | N.A. | 373 | 1.13 | 0.55 | 8 | 0 | 8 | 69 | 9.13 |
| [18F]SP203 |
|
mGlu5 | 7.0 [165] | 5.9 [166] | 260 | 2.18 | 3.66 | 2 | 0 | 1 | 37 | NA |
| [18F]FECNT |
|
DAT | 7.5 [167] | 7.5 [167] | 325 | 2.64 | 3.47 | 3 | 0 | 3 | 30 | 6.99 |
| [18F]Fallypride |
|
D2 | ~ 8.0 | ~ 10 | 364 | 3.33 | 5 | 1 | 4 | 51 | 8.70 | |
| Criteria: | ||||||||||||
| [168] | > 1.5 & < 2.7 | |||||||||||
| [169] | < 450 | < 90 | ||||||||||
| [170] | ≤ 400 | < 5 | ≤ 3 | ≤ 7 | ||||||||
| [171] | < 70 | |||||||||||
| [172] | ≤ 5 | |||||||||||
| [172] | > logP | |||||||||||
| [173] | < 500 | 2–5 | 2–5 | < 3 | < 90 | |||||||
| [174] | < 400 | < 4.0 | ||||||||||
| (MDR + LDR) (I) [175] | < 351 | < 2.8 | < 4.0 | < 2 | 32–86 | < 9.5 |
a
Listed in ascending order of peak brain uptake in monkey. Unreferenced values are from the author’s laboratory.
b
Weighted mean of reported values, or of reported range for reported region of highest uptake. Unreferenced values are from the author’s laboratory.
c
For non-labeled compound.
d
From reference [176], unless otherwise indicated.
e
Counted as hetero atoms having a lone electron pair.
f
Counted as electronegative atoms bonded to H.
g
From ChemDraw.
h
From Pallas software.