Tetrahydropyran is widely used as a solvent and reaction intermediate in organic synthesis. Its stability and polarity make it suitable for various chemical transformations, especially in pharmaceutical and fine chemical industries. It serves as a protective group for alcohols in the form of tetrahydropyranyl (THP) ethers, allowing selective reactions at other functional sites in complex molecules. This protecting group is easily introduced and removed under mild acidic conditions, making it valuable in multi-step synthesis. Additionally, tetrahydropyran rings are structural motifs in numerous natural products and bioactive compounds, particularly in polyether antibiotics and marine toxins, where they contribute to molecular rigidity and biological activity. Its presence in such compounds underscores its importance in medicinal chemistry and drug design.