Improved synthesis of β-CIT and [11C]β-CIT labeled at nitrogen or oxygen positions

Qi-Huang Zheng, G. Keith Mulholland

Research output: Contribution to journalArticle

55 Citations (Scopus)

Abstract

The important radiotracer precursor 2β-carbomethoxy-3β-(4-iodophenyl)-tropane (β-CIT, RTI-55) was made in 52% overall yield from cocaine. Key steps were improved conjugate Grignard addition to anhydroecgonine methyl ester with >3.5:1 2β: 2α-isomer selectivity, and a mild new direct aromatic iodination with I2 and silver triflate in CH2Cl2. The [11C]β-CIT was labeled at either the N or O positions with [11C]methyl triflate; and efficient reversed-phase HPLC was used to preparatively separate [N-11C]β-CIT from N-nor-β-CIT for the first time, and a fast solid-phase extraction (SPE) method was applied to preparatively separate [O-11C]β-CIT from β-CIT-acid precursor.

Original languageEnglish
Pages (from-to)981-986
Number of pages6
JournalNuclear Medicine and Biology
Volume23
Issue number8
DOIs
StatePublished - Nov 1996

Fingerprint

Nitrogen
Oxygen
Halogenation
Solid Phase Extraction
Cocaine
High Pressure Liquid Chromatography
Acids
RTI 55
methyl triflate
anhydroecgonine methyl ester
trifluoromethanesulfonic acid
N-nor-3-(4'-iodophenyl)tropane-2-carboxylic acid methyl ester

Keywords

  • carbon-11
  • iodination
  • monoamine transporter
  • phenyltropane
  • RTI-55

ASJC Scopus subject areas

  • Cancer Research
  • Molecular Medicine
  • Radiology Nuclear Medicine and imaging

Cite this

Improved synthesis of β-CIT and [11C]β-CIT labeled at nitrogen or oxygen positions. / Zheng, Qi-Huang; Mulholland, G. Keith.

In: Nuclear Medicine and Biology, Vol. 23, No. 8, 11.1996, p. 981-986.

Research output: Contribution to journalArticle

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