isoprenoides

Isoprenoids, also known as terpenoids, are a large and diverse class of organic compounds derived from repeating units of a five-carbon molecule called isoprene. These compounds are ubiquitous in nature, found in plants, animals, and microorganisms. The basic isoprene unit, with the chemical formula C5H8, is linked together in various ways to form longer chains or cyclic structures.

The simplest isoprenoids are built from two isoprene units, forming C10 compounds called monoterpenes. Examples include menthol and limonene, which contribute to the scent of mint and lemons, respectively. Molecules formed from three isoprene units (C15) are sesquiterpenes, like farnesene. Four isoprene units create diterpenes (C20), such as vitamin A and gibberellins, plant hormones involved in growth.

Larger isoprenoids include triterpenes (C30), like squalene, a precursor to steroids. Tetraterpenes (C40) include carotenoids such as beta-carotene, the pigment responsible for the orange color in carrots. Even larger structures, like natural rubber, are polymers of isoprene units. Many isoprenoids have significant biological functions, acting as pigments, hormones, vitamins, and defense compounds. They also play a crucial role in the fragrance and flavor industries.