Isopiperitone (CAS 58615-39-7) is a p-menthane monoterpenoid ketone structurally related to piperitone; owing to its minty–herbal, slightly camphoraceous and citrusy nuance, it is used at trace levels by perfumers and flavorists as a modifier to sharpen mint, eucalyptus, rosemary, and pine accords, and in oral-care flavors, chewing gum, and lemon–mint beverages. In synthesis and fragrance development, isopiperitone serves as a versatile intermediate for accessing related monoterpenone/enone derivatives and as a substrate for Michael additions, oxime/semicarbazone formation, selective hydrogenation, or epoxidation, supporting route optimization from biogenic feedstocks. In analysis, it is employed as a GC–MS reference/standard for essential-oil fingerprinting of Mentha and Eucalyptus species and for postharvest change monitoring, as well as a model molecule for structure–odor relationship studies and volatility kinetics in flavor matrices. In bio-oriented applications, isopiperitone has been investigated at laboratory scale for insect-repellent/inhibitory, antimicrobial, and antioxidant activities typical of monoterpenes, suggesting potential as a co-ingredient in natural preservation and biobased agriculture; however, safety, stability, and formulation compatibility must be validated before practical use. Note that it is volatile and prone to oxidation; store tightly closed, protected from light/oxygen, and comply with local regulations for use in consumer products.
