Method for production of F-18 labeled amyloid beta ligands

1. A method for producing an injectable formulation of a compound of Formula I suitable for injection into humans

comprising the steps of:

Step 1: radiolabeling a compound of Formula II with a F-18 fluorinating agent, to obtain a compound of Formula I, if R═H or to obtain compound of Formula III, if R=PG

Step 2: if R=PG, cleaving the protecting group PG to obtain a compound of Formula I, and

Step 3: purifying and formulating a compound of Formula I

wherein:

n=3,

X is selected from the group consisting of

a) CH, and

b) N,

R is selected from the group consisting of

a) H, and

b) PG,

PG is an amine-protecting group, and

LG is a leaving group,

wherein Step 3 comprises purifying and formulating a compound of formula I using a HPLC separation using an HPLC solvent eluent consisting of an ethanol/aqueous buffer mixture and wherein the fraction obtained from the HPLC purifying is part of an injectable formulation of a compound of formula I suitable for injection into humans, and

wherein the radioactive level of the injectable formulation prepared by the method is more than 50 GBq, wherein the radiochemical purity of the injectable formulation prepared by the method is >95%.

2. The method according to claim 1 , wherein PG is selected from the group consisting of:

a) Boc,

b) Trityl and

c) 4-Methoxytrityl.

3. The method according to claim 1 , wherein LG is selected from the group consisting of:

a) Halogen and

b) Sulfonyloxy,

wherein Halogen is chloro, bromo or iodo.

4. The method according to claim 3 , wherein LG is Sulfonyloxy and it is selected from the group consisting of:

a) Methanesulfonyloxy,

b) p-Toluenesulfonyloxy,

c) (4-Nitrophenyl)sulfonyloxy, and

d) (4-Bromophenyl)sulfonyloxy.

5. The method according to claim 1 , wherein X═CH.

6. The method according to claim 1 , wherein X═CH, R═H or Boc, and LG=Methanesulfonyloxy or p-Toluenesulfonyloxy.

7. The method according to claim 1 , wherein the aqueous buffer is a solution of sodium chloride, sodium phosphate buffer, ascorbic acid, ascorbate buffer, or a mixture thereof.

8. The method of claim 1 , wherein no re-formulation to remove constituents of the HPLC solvent is performed.

9. The method of claim 1 , wherein the collected product fraction after HPLC is not trapped on a solid-phase extraction cartridge.

10. The method of claim 8 , wherein the collected product fraction after HPLC is not trapped on a solid-phase extraction cartridge.

11. The method of claim 1 , wherein radioactive level of the injectable formulation prepared by the method is more than 100 GBq.

12. The method of claim 1 , wherein the HPLC method is conducted only with HPLC solvent or solvent mixture which would be suitable for injection into humans.

13. The method of claim 1 , wherein the radiochemical purity of the injectable formulation prepared by the method is >98%.

14. The method of claim 1 , wherein the radiochemical purity of the injectable formulation prepared by the method is ≧99%.