PRINCIPLES OF CARBON-U (C-11) RADIO-CHEMISTRY

ABSTRACT

Carbon –U (C-11) radiotracers are widely used for the early diagnosis of cancer, monitoring therapeutic response to cancer treatment and pharmacokinetic investigations of anticancer drugs. PET imagining permits non-invasive monitoring of metabolic processes and molecular targets, while carbon-II radiotracers allow a “hot-for cold” substitution of biological active molecules. Advance in organic synthetic chemistry and radiochemistry as well as improved automated techniques for radiosynthesis have encouraged investigators in developing carbon-II  tracers for use in oncology imagining studies. The short half-life of carbon –II (20.38 minutes)  creates specially challanges for the synthesis of carbon –II labeled tracers: these include high radiochemical parity and high specific activity in a  short time and on a very  small  scale. The optimization  of conditions for  makers a carbon-II tracer include the late introduction of the carbon-II Isotope, the rapid formation and purification of the target compound, and the used automated system to afford a high  yield of the target compound in a short time. In this review paper, we first briefly introduced some basic principles.

PET imaging of cancer, we then discuss principles of C-II radiochemistry, focus on specific advances in radiochemistry and describe the synthesis of carbon-II radiopharmaceuticals developed for cancer imaging. The carbon-II radio chemistry approaches described include the  N,D and S-alkylation of (C-II) methyl iodide (C-11) methyl triflate and analogues of (C-11) methyl iodide and heir application for making carbon-II tracers; we then address recent advances in exploring a trans metallic complied medicate (C-11) carbonyl reaction for oncologic targets.