Improved method for preparing Ni(II) complex of (S)-tyrosine Schiff base and its use in the automated synthesis of O-(2′-[18F]fluoroethyl)-l-tyrosine using solid-phase extraction purification. (September 2017)

• Record Type: Journal Article
• Authors: Lakshminarayanan, N.; Kumar, Amit; Roy, Sushant; Pawar, Yogita; Chaudhari, Pradip; Rajan, M.G.R.
• Is Part Of: Applied radiation and isotopes. Volume 127(2017:Sep.)
• Page Start: 122
• Page End: 129
• Publication Date: 2017-09
• Subjects: 18F-fluoroethyltyrosine -- Automated synthesis -- Ni(II)-(S)BPB-Tyr Complex precursor -- Tumor imaging; Radiology -- Periodicals; Radiation -- Industrial applications -- Periodicals; Nuclear chemistry -- Periodicals; Internet resource; Periodical; 660.298
• DOI: 10.1016/j.apradiso.2017.05.017
• Languages: English
• ISSNs: 0969-8043

Abstract

Abstract: O-(2′-[ 18 F]fluoroethyl)-l -tyrosine is reportedly suitable for PET-imaging of brain tumours. We report here the synthesis of Ni(II)-complex of Schiff's base (S)-[N-2-(N′-benzylprolyl)amino]-benzophenone, ((S)BPB) and alkylatedl -tyrosine precursor, Ni(II)-(S)-BPB-l -Tyr-O-CH2 -CH2 -OTs by an improved method. A fully-automated radio-synthesis including non-HPLC purification was developed with a radio-chemical yield of 24.6 ± 2% in 70 ± 2 min (n = 5). Radiochemical and enantiomeric purity was > 98% and 94% respectively. Bio-distribution and micro-PET studies in C57BL/6 mice bearing B16F10 melanoma showed tumor to brain ratio of 3.36 and 3.62 respectively at 60 min post-injection. Highlights: Improved method for synthesis of Ni(II)-(S)-BPB-l -Tyr-O-CH2-CH2-OTs precursor for [ 18 F]FET. Automated radio-synthesis of [ 18 F]FET including SPE purification with 24.6% yield. Radiochemical purity > 98% and enantiometric purity > 94%. Micro-PET studies in C57BL/6 mice with B16F10 melanoma showed tumor to brain ratio of 3.62 at 60 min.