Synthesis and 11C-Radiolabelling of 2-Carboranyl Benzothiazoles

Molecules. 2015 Apr 23;20(5):7495-508. doi: 10.3390/molecules20057495.

Abstract

Dicarba-closo-dodecaboranes, commonly known as carboranes, possess unique physico-chemical properties and can be used as hydrophobic moieties during the design of new drugs or radiotracers. In this work, we report the synthesis of two analogues of 2-(4-aminophenyl)benzothiazole (a compound that was found to elicit pronounced inhibitory effects against certain breast cancer cell lines in vitro) in which the phenyl ring has been substituted by a m-carborane cage. Two different synthetic strategies have been used. For the preparation of 1-(9-amino-1,7-dicarba-closo-dodecaboran-1-yl)-benzo-thiazole, the benzothiazole group was first introduced on one of the cluster carbon atoms of m-carborane and the amine group was further attached in three steps. For the synthesis of 1-(9-amino-1,7-dicarba-closo-dodecaboran-1-yl)-6-hydroxybenzothiazole, iodination was performed before introducing the benzothiazole group, and the amino group was subsequently introduced in six steps. Both compounds were radiolabelled with carbon-11 using [11C]CH3OTf as the labelling agent. Radiolabelling yields and radiochemical purities achieved should enable subsequent in vitro and in vivo investigations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzothiazoles / chemical synthesis*
  • Benzothiazoles / chemistry
  • Boron Compounds / chemical synthesis*
  • Boron Compounds / chemistry
  • Carbon Radioisotopes / chemistry
  • Positron-Emission Tomography / methods*
  • Radiopharmaceuticals / chemical synthesis*
  • Radiopharmaceuticals / chemistry

Substances

  • 2-(4-aminophenyl)benzothiazole
  • Benzothiazoles
  • Boron Compounds
  • Carbon Radioisotopes
  • Radiopharmaceuticals