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.
Tetrahydrothiophene is a sulfur-containing saturated heterocyclic compound obtained by catalytic hydrogenation of thiophene. After thiophene is reduced to tetrahydrothiophene, it no longer has a conjugated system and aromaticity. Therefore, tetrahydrothiophene shows the properties of general thioethers. Easily oxidized to sulfoxides and sulfones. Tetrahydrothiophene can be used as a raw material for the production of pharmaceuticals, pesticides and photochemicals.