Recent Progress in the Synthetic Methods of Pyrazoloquinoline Derivatives

The focus of this review is on the synthetic routes available for different types of pyrazoloquinoline derivatives. There are three types of synthetic methods: i) from pyrazole derivatives; ii) from quinoline derivatives; and iii) miscellaneous methods. The position of the linkage between pyrazole and quinoline rings determines the seven isomers of pyrazoloquinolines. The purpose of this review is to provide a guide for both synthetic and medicinal chemists to discover and design new pyrazoloquinolines for medical purposes.