Isoprene (short for isoterpene), or 2-methyl-1,3-butadiene, is a common organic compound with the formula CH2=C(CH3)CH=CH2. Under standard conditions it is a colorless liquid. However, this compound is highly volatile because of its low boiling point.
Isoprene (C5H8) is the monomer of natural rubber and also a common structure motif to an immense variety of other naturally occurring compounds, collectively termed the isoprenoids. Molecular formula of isoprenoids are multiples of isoprene in the form of (C5H8)n, and this is termed the isoprene rule. The functional isoprene units in biological systems are dimethylallyl diphosphate (DMADP) and its isomer isopentenyl diphosphate (IDP).
The singular terms â€œisopreneâ€ and â€œterpeneâ€ are synonymous whereas the plurals â€œisoprenesâ€ or â€œterpenesâ€ refer to terpenoids (isoprenoids).