Coumarin occurs naturally in a variety of plants, such as lentils, sweet sawdust, vanilla grass, and sweet grass. Coumarin has a simple structure, benzopyrone, associated with different reaction centers. Coumarins are further subdivided into different classes: simple coumarins, pyranocoumarins, furanocoumarins, dicoumarins and isocoumarins. Coumarin derivatives are an important class of natural plant metabolites with various biological activities. They can also be synthesized artificially, and various synthetic coumarin derivatives (azoles, sulfonyls, furans, pyrazoles, etc.) have shown good anticancer, antitumor and antiproliferative activities. Coumarin derivatives are not only effective anticancer agents, but also possess minimum side effects. Based on different substitution patterns, these potential active substances show a great ability to modulate potential anticancer activities.
Phthalazine is a heterocyclic compound with the molecular formula C8H6N2 composed of a benzene ring fused with a pyridazine ring. Phthalazine and its derivatives do not exist in nature. Phthalazines are used as starting materials for organic synthesis. Studies have found that phthalazine has a variety of physiological activities, such as anti-cancer, antibacterial, anti-inflammatory and so on. The synthesis of phthalazine compounds with novel structures and better biological activities has become a research hotspot in recent years.