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Terpenes

  • Page ID
    40275
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    Terpenes and terpenoids are two classes of naturally occurring compounds that are formally derived from isoprene (1).

    terpenes1.png

    For identification purposes, the five carbon atoms in isoprene are numbered as follows.

    terpenes2.png

    Carbon 1 is called the head of the molecule; carbon 4 is called the tail. Since the isoprene molecule has five carbon atoms, the number of carbon atoms in the molecule of a terpene/terpenoid is a multiple of five.

    The difference between terpenes and terpenoids is that terpenes are hydrocarbons, whereas terpenoids contain oxygen. Organic chemists increasingly use the words terpene and terpenoid interchangeably. When plant matter (leaves, roots, flowers, etc.) is subjected to steam distillation, an oily liquid called essential oil is obtained. An essential oil is a mixture of terpenes and/or terpenoids. eg:

    terpenes3.png

    see also monoterpene, sesquiterpene, diterpene, triterpene, isoprene unit, isoprene rule, irregular terpene


    This page titled Terpenes is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Gamini Gunawardena via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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