NOVEL IMAGING COMPOUNDS

1 . A compound of formula (I):

and all stereoisomers and mixtures thereof, pharmaceutically acceptable salts, hydrates, solvates and polymorphs thereof;

wherein

is selected from a 5- to 7-membered monocyclic group and a 7- to 9-membered bicyclic group, which can optionally contain a heteroatom selected from N and O in addition to the nitrogen atom which is attached to the tricyclic group and wherein

is substituted by a substituent R and is optionally substituted by a substituent R*;

wherein

R is selected from F—, alkylene which is substituted by F, (alkylene-oxy) n - which is substituted by F, (alkylene-oxy) n -alkylene-which is substituted by F, and alkylene-oxy which is substituted by F and OH;

R* is selected from hydroxy, methoxy, methyl and hydroxymethyl;

n is selected from 1, 2 and 3; and

F is [F-19]fluoro or [F-18]fluoro.

2 . The compound according to claim 1 , wherein

is selected from

3 . The compound according to claim 1 , wherein R is selected from F—, F—CH 2 CH 2 OCH 2 CH 2 —, F—CD 2 CH 2 CH 2 O—, F—CH 2 CH 2 O—, F—(CH 2 CH 2 O) 2 —, F—CH 2 CH 2 O—CH 2 —, F—(CH 2 CH 2 O) 2 —CH 2 —, F—CH 2 CH 2 CH 2 O—, F—CH 2 CH(OH)CH 2 O—, F—CH 2 CH(F)CH 2 O—, HO—CH 2 CH(F)CH 2 O— and F—CH 2 —CH(CH 2 OH)—O—.

4 . The compound according to claim 1 , wherein if R is attached to a N-atom, R is selected from F—CH 2 CH 2 —, F—CH 2 CH 2 OCH 2 CH 2 —, F—CH 2 CH 2 CH 2 —, F—CH 2 CH(OH)CH 2 — and HO—CH 2 CH(F)CH 2 —.

5 . The compound according to claim 1 , wherein the compound is selected from a compound of formula (IA), (IB), (IC), (ID), (IE), (IF), (IG), (IH) and (IJ):

wherein R is as defined in any one of claim 1 , 3 , or 4 .

6 . A compound of formula (II):

and all stereoisomers and mixtures thereof, pharmaceutically acceptable salts, hydrates, solvates and polymorphs thereof;

wherein

is selected from a 5- to 7-membered monocyclic group and a 7- to 9-membered bicyclic group, which can optionally contain a heteroatom selected from N and O in addition to the nitrogen atom which is attached to the tricyclic group and wherein

is substituted by a substituent R p and is optionally substituted by a substituent R**;

wherein

R p is selected from LG-, alkylene which is substituted by LG, (alkylene-oxy) n - which is substituted by LG, (alkylene-oxy) n -alkylene- which is substituted by LG, and alkylene-oxy which is substituted by LG and OPG 2 ;

R** is selected from hydroxy, OPG 2 , methoxy, methyl, hydroxymethyl and PG 2 -O-methyl;

n is selected from 1, 2 and 3;

R 1 is —H or PG 1 , wherein PG 1 is an amine protecting group;

PG 2 is a hydroxy protecting group; and

LG is a leaving group.

7 . A diagnostic composition comprising a compound according to claim 1 and a pharmaceutically acceptable carrier, diluent, adjuvant or excipient.

8 . (canceled)

9 . (canceled)

10 . (canceled)

11 . (canceled)

12 . A method of imaging of tau aggregates comprising administering an effective amount of a compound according to claim 1 to a patient in need thereof.

13 . A method of diagnosing a disorder associated with tau aggregates or a tauopathy comprising administering an effective amount of a compound according to claim 1 to a patient in need thereof.

14 . The method according to claim 13 , wherein the disorder is selected from Alzheimer's disease (AD), familial AD, Creutzfeldt-Jacob disease, dementia pugilistica, Down's Syndrome, Gerstmann-Sträussler-Scheinker disease, inclusion-body myositis, prion protein cerebral amyloid angiopathy, traumatic brain injury, amyotrophic lateral sclerosis, Parkinsonism-dementia complex of Guam, non-Guamanian motor neuron disease with neurofibrillary tangles, argyrophilic grain disease, corticobasal degeneration, diffuse neurofibrillary tangles with calcification, frontotemporal dementia with Parkinsonism linked to chromosome 17, Hallervorden-Spatz disease, multiple system atrophy, Niemann-Pick disease type C, pallido-ponto-nigral degeneration, Pick's disease, progressive subcortical gliosis, progressive supranuclear palsy (PSP), subacute sclerosing panencephalitis, tangle only dementia, postencephalitic Parkinsonism, myotonic dystrophy, tau panencephalopathy, AD-like with astrocytes, certain prion diseases (GSS with tau), mutations in LRRK2, Hallervorden-Spatz disease, chronic traumatic encephalopathy, familial British dementia, familial Danish dementia, frontotemporal lobar degeneration, Guadeloupean Parkinsonism, neurodegeneration with brain iron accumulation, SLC9A6-related mental retardation, and white matter tauopathy with globular glial inclusions; preferably Alzheimer's disease.

15 . A method of preparing a compound of formula (I) as defined in claim 1 , comprising reacting a compound of formula (II)

including any stereoisomers or mixtures thereof, pharmaceutically acceptable salts, hydrates, solvates and polymorphs thereof;

and wherein

is selected from a 5- to 7-membered monocyclic group and a 7- to 9-membered bicyclic group, which can optionally contain a heteroatom selected from N and O in addition to the nitrogen atom which is attached to the tricyclic group and wherein

is substituted by a substituent R p and is optionally substituted by a substituent R**;

wherein

R p is selected from LG-, alkylene which is substituted by LG, (alkylene-oxy) n - which is substituted by LG, (alkylene-oxy) n -alkylene- which is substituted by LG, and alkylene-oxy which is substituted by LG and OPG 2 ;

R** is selected from hydroxy, OPG 2 , methoxy, methyl, hydroxymethyl and PG 2 -O-methyl;

n is selected from 1, 2 and 3;

R 1 is —H or PG 1 , wherein PG 1 is an amine protecting group;

PG 2 is a hydroxy protecting group; and

LG is a leaving group.

with an 18 F-fluorinating agent, so that the leaving group LG is replaced by 18 F.

16 . The method of claim 12 , wherein the imaging comprises positron emission tomography.

17 . The method of claim 15 , further comprising cleaving of the protecting group PG 1 or PG 2 , if present