The present invention relates to a radioactive iodine-labeled pyrido[1,2-a]benzimidazole derivative compound represented by a definite general formula or a salt thereof, or a radiopharmaceutical comprising the same.

The present invention provides a method of imaging a subject's lung which comprises contacting the subject's lung with a matrix metalloproteinase inhibitor labeled with a radioisotope under conditions such that the inhibitor binds to matrix metalloproteinase in the lung, and then imaging the radiolabeled inhibitor bound to matrix metalloproteinase in the subject's lung. The invention also provides Ro 32-3555 labeled with a radioisotope.

Provided are imaging agents comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof, and methods of their use.

##STR00001##

6-[.sup.18F]Fluoro-2-alkoxynicotinoyl substituted Lys-C(O)-Glu derivatives were identified as efficient imaging probes for PSMA expressing tissues in comparison to other known PSMA specific ligands like [.sup.18F]DCFPyL, [.sup.68Ga]HBED-CC-PSMA, [.sup.18F]PSMA-1007 and [Al.sup.18F]HBED-CC-PSMA. Unexpectedly, the 6-[.sup.18F]fluoro-2-alkoxy and 6-[.sup.18F]fluoro-4-alkoxy substituted analogs showed significant differences in accumulation in PSMA expressing prostate tumor cells. Whereas the 2-alkoxy derivative showed cellular uptake values higher than [.sup.18F]DCFPyL, the cellular uptake of the corresponding 4-alkoxy substituted derivative was significantly lower. Furthermore, in vivo PET studies with 2-alkoxy-substituted probes demonstrated excellent visualization of PSMA positive ganglia with extremely high target to background ratio. In contrast, the 4-alkoxy substituted derivatives showed less favorable biodistribution with significantly lower uptake in PSMA positive tissues. Especially, the .sup.18F-labeled 2-methoxy derivate ((2S)-2-({[(1S)-1-carboxy-5-[(6-[.sup.18F]fluoro-2-methoxypyridin-3-yl)formamido]pentyl]carbamoyl}-amino)pentanedioic acid) demonstrated exceptional clinical efficiency in detecting small PCa lesions, including those which could not be visualized with [.sup.68Ga]HBED-CC-PSMA representing currently the gold standard for the diagnosis of recurrent PCa. Furthermore, this probe is easily accessible on a preparative scale in commercially available automated synthesis modules like GE FASTlab and TRACERlab FX N Pro. Consequently, the novel probe is a valuable tool for the visualization of ganglia and reendothelialization as well as for the diagnosis of glioma, neuropathic pain and atherosclerotic plaques.

The present invention relates to a compound represented by the following General Formula (1) or a salt thereof.

##STR00001##

In General Formula (1), R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each independently represent a hydrogen atom, a linear or branched alkyl group which may have a substituent or the like. R.sup.1 and R.sup.2 may be bonded to each other to form a ring. R.sup.3 and R.sup.4 may be bonded to each other to form a ring. R.sup.1 and/or R.sup.2 may be bonded to a 6-membered ring to which —NR.sup.1R.sup.2 is bonded to form a ring. R.sup.3 and/or R.sup.4 may be bonded to a 6-membered ring to which —NR.sup.3R.sup.4 is bonded to form a ring. R.sup.5 represents —.sup.11CH.sub.3, a linear or branched alkyl group which may have a substituent or the like. R.sup.6 represents —F, —.sup.18F or the like. X, Y and Z each independently represent a carbon atom, an oxygen atom or the like. n is 0 or 1.

In one aspect, the invention comprises compounds that bind to the synaptic vesicle protein SV2A and that can be useful as radiotracers for positron emission tomography. In another aspect, the invention comprises methods of imaging the brain, measuring synaptic density or diagnosing neurological diseases such as Alzheimer's disease, psychiatric disorders such as depression, and metabolic disorders such as diabetes comprising detecting the compounds of the invention by positron emission tomography (PET).

Provided herein are certain compounds and imaging agents useful for detecting a disease or condition associated with protein aggregation, compositions thereof, and methods of their use.

Kits for the preparation, synthesis, and delivery of compositions comprising a conjugate of a nucleoside analog, a chelator, and a label for use as imaging and therapeutic agents. The kits, as well as methods for their use, may be used in diagnosing, treating, or monitoring the progression of infectious diseases and/or symptoms or complications resulting from infection.

The present invention provides a novel radioactive compound for imaging malignant melanoma and a use thereof as a contrast agent for PET imaging.

The subject invention concerns materials and methods for treating and/or preventing diseases associated with accumulation of Aβ peptide in neural tissue. The subject invention also concerns materials and methods for treating and/or preventing stress disorders, such as post-traumatic stress disorder (PTSD). In one embodiment, a method of the invention comprises administering a therapeutically effective amount of cotinine, or a pharmaceutically acceptable salt thereof, to a person or animal in need of treatment. The methods of the invention can be used to prevent and/or treat Alzheimer's disease, Parkinson's disease, and/or Down's syndrome. The subject invention also concerns compositions that comprise cotinine, or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier, diluent or adjuvant. The subject invention concerns materials and methods for detecting and diagnosing conditions associated with accumulation of Aβ peptide in neural tissue, such as Alzheimer's disease and Parkinson's disease, using the chemical cotinine. In one embodiment, the method comprises administering cotinine labeled with a detectable label to a person or animal. The presence of labeled cotinine in neural tissue is then determined. The level and/or location of cotinine can be analyzed and a diagnosis made. The subject invention also concerns cotinine labeled with a detectable label. In one embodiment, the cotinine is labeled with a radioisotope that can be detected by Positron Emission Tomography (PET) or single photon emission computed tomography (SPECT).