@article{3142796,
    title = "[Br-76]BMK-I-152, a non-peptide analogue for PET imaging of
corticotropin-releasing hormone type 1 receptor (CRHR1)",
    author = "Lang, L. and Ma, Y. and Kim, B. M. and Jagoda, E. M. and Rice, K. C. and and Szajek, L. P. and Contoreggi, C. and Gold, P. W. and Chrousos, G. P. and and Eckelman, W. C. and Kiesewetter, D. O.",
    journal = "Journal of Labelled Compounds and Radiopharmaceuticals",
    year = "2009",
    volume = "52",
    number = "9-10",
    pages = "394-400",
    publisher = "Wiley-Blackwell",
    issn = "0362-4803, 1099-1344",
    doi = "10.1002/jlcr.1616",
    keywords = "corticotropin-releasing hormone; radiobromination; bromine-76; CRH; PET",
    abstract = "The study of corticotropin-releasing hormone is of significant interest
in mental health. We have developed a radiobromination procedure for the
preparation of [Br-76]BMK-I-152, a high-affinity
corticotropin-releasing hormone type 1 receptor antagonist. The
radiobromination procedure resulted in the formation of two
radiobrominated products from the same trialkyltin precursor. Utilizing
the results of several reaction conditions and the chromatographic and
mass spectral data obtained from Waters Acquity and Q-TOF, we determined
that both 3-bromo and 4-bromo isomers could be obtained. The authentic
sample of the 3-bromo isomer was prepared to confirm the identity of a
previously unknown radioactive side product; affinity assays revealed
that the 4-bromo isomer had similar to 70 times higher affinity than
that of the 3-bromo compound. By manipulation of reaction conditions,
the individual products could be selected. Under no-carrier-added
conditions at room temperature in aqueous acetonitrile, the major
radioactive product (>80%) was identified as the
3-[Br-76]bromo-4-tributylstannyl analogue of BMK-I-152. The
4-[Br-76]bromo isomer accounted for less than 1% of the total
activity. The 3-[Br-76]bromo BMK-I-152 could be obtained by treating
this intermediate with trifluoroacetic acid to effect removal of the
trialkyltin. if the radiobromination was conducted after first
evaporating the water from the aqueous ammonium hydroxide solution of
[Br-76]bromide, the desired 4-[Br-76]bromo isomer was obtained with
a 58% radiochemical yield."
}