Pyrazolo[4,5-c]quinolines. 3. Synthesis, receptor binding, and 13C NMR study

Some 1-aryl-3-methylpyrazolo[4,5-c]quinolin-4-ones, were prepared and tested for their ability to displace specific [3H]flunitrazepam binding from bovine brain membranes. The 1-meta-aryl derivatives were the compounds that bound with the highest affinity within this class. Our 13C NMR study suggested a correlation between the binding affinity and the chemical shift value of a carbon atom of the tricyclic system.