Improved Syntheses of Precursors for PET Radioligands [F]XTRA and [F]AZAN

Overview

Journal Tetrahedron Lett

Publisher Elsevier

Specialty Chemistry

Date 2010 Sep 14

PMID 20835363

Citations 2

Authors

Yongjun Gao

Haofan Wang

Ronnie C Mease

Martin G Pomper

Andrew G Horti

Affiliations

Soon will be listed here.

Abstract

Improved syntheses of 7-methyl-2-exo-[3'-(2-bromopyridin-3-yl)-5'-pyridinyl]-7-azabicyclo[2.2.1]heptanes (3) and 7-methyl-2-exo-[3'-(6-bromopyridin-2-yl)-5'-pyridinyl]-7-azabicyclo[2.2.1]heptanes (4), precursors for PET radioligands [(18)F]XTRA (1) and [(18)F]AZAN (2), involving a key Stille coupling step followed by deprotection of Boc group and N-methylation are described. The new synthetic procedures provided the title compounds in more than 40% overall yields.

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