Pyrones or pyranones are a class of heterocyclic chemical compounds. They contain an unsaturated six-membered ring containing one oxygen atom and a ketone functional group. There are two isomers denoted as 2-pyrone and 4-pyrone. 2-Pyrone is used in organic synthesis as a building block for more complex chemical structures because it may participate in a variety of cycloaddition reactions to form bicyclic lactones. Pyrone derivatives are extremely prevalent structural motif in diverse naturally and synthetically occurring bioactive molecules having a broad array of chemotherapeutic potentials.
Pyrans are an important class of six-membered heterocyclic compounds, non-aromatic rings, composed of five carbon atoms and one oxygen atom, and contain two double bonds. The molecular formula of pyran is C5H6O, and there are two isomers. Pyrans, together with benzo derivatives, form scaffolds for a variety of drug applications, many of which are approved and promising candidates in clinical trials and recently isolated bioactive natural products.
Benzene is an important organic compound with the chemical formula C6H6, and its molecule consists of a ring of 6 carbon atoms, each with 1 hydrogen atom. Benzene is a sweet, flammable, colorless and transparent liquid with carcinogenic toxicity at room temperature, and has a strong aromatic odor. It is insoluble in water, easily soluble in organic solvents, and can also be used as an organic solvent itself. The ring system of benzene is called benzene ring, and the structure after removing one hydrogen atom from the benzene ring is called phenyl. Benzene is one of the most important basic organic chemical raw materials. Many important chemical intermediates can be derived from benzene through substitution reaction, addition reaction and benzene ring cleavage reaction.