Synthesis of novel conformationally constrained pyrazolo[4,3-c]quinoline derivatives as potential ligands for the estrogen receptor

Abstract

The preparation of three novel classes of pyrazolo[4,3-c]quinoline derivatives is reported. The easily accessible 2,3-dihydro-1H-quinolin-4-ones were used as the starting materials and were functionalized with three different acylating agents affording their respective constrained core substrates. The latter by condensation with phenyl(or 4-methoxyphenyl)hydrazines and subsequent debenzylation or demethylation provided the desired pyrazole derivatives. Some interesting features emerged with respect to the regioselectivity and mechanism of these reactions. © Georg Thieme Verlag Stuttgart