Synthesis and analysis of 2-[211At]-L-phenylalanine and 4-[211At]-L-phenylalanine and their uptake in human glioma cell cultures in-vitro.
2-[211At]-L-phenylalanine and 4-[211At]-L-phenylalanine were prepared from the corresponding iodo and bromo derivatives using the Cu(+)-assisted nucleophilic exchange. 4-[211At]-L-phenylalanine was additionally prepared by destannylation of the BOC-derivatized 4-tributylstannyl-L-phenylalanine. Radiochemical yields of 2-[211At]-L-phenylalanine and 4-[211At]-L-phenylalanine by nucleophilic exchange were 52-74% and 65-85%. Radiochemical yield of 4-[211At]-L-phenylalanine by electrophilic destannylation was 35-50%. HPLC sequence analysis showed that 2-[211At]-L-phenylalanine followed the halogen sequence (F<Cl<Br<I<At) whereas 4-[211At]-L-phenylalanine eluted between 4-Br-L-phenylalanine and 4-I-L-phenylalanine (F<Cl<Br<At<I), independent on the production pathway. Uptake of 4-[211At]-L-phenylalanine and 4-[131I]-L-phenylalanine in DBTRG-05MG glioma cells was inhibited by l-phenylalanine 7-fold and 6-fold, respectively.
Medizinische Hochschule Hannover, Nuklearmedizin Carl-Neuberg Str. 1, D-30623 Hannover, Germany. meyer.geerd-j@mh-hannover.de
Geerd J
GJ
Meyer
Almut
A
Walte
Siva R
SR
Sriyapureddy
Michaela
M
Grote
Doris
D
Krull
Zekiye
Z
Korkmaz
Wolfram H
WH
Knapp
D001246:Astatine; D001932:Brain Neoplasms / Q000378:metabolism*; D045744:Cell Line, Tumor; D005910:Glioma / Q000378:metabolism*; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000378:metabolism; D019275:Radiopharmaceuticals / Q000378:metabolism*
D019275:Radiopharmaceuticals; D010649:Phenylalanine; D001246:Astatine