MONOTERPENOIDS
The chemical, Menthol , a typical terpene, and Menthone, a ketone terpenoid which are the main aroma compounds in oil of peppermint which is prepared by distillation of the flowers of Corn Mint. Corn Mint also contains Menthyl Acetate , an ester. It is used in some toothpastes (others might use oil of spearmint where the dominant aromatic compound is Carvone).
Menthone is a monoterpenoid with a minty flavour and odour. It occurs in the essential oils of a number of plants such as Pennyroyal, Peppermint, Corn Mint , Pelargonium geraniums and Ground-Ivy (Glechoma hederaceae). There are 4 possible stereoisomers of it, but just one of those is is the most abundant in nature. Menthone is used for flavouring and in perfume and other cosmetics.
IsoMenthone is one of the four possible stereoisomers of Menthone and it too is found in Corn Mint.
Pulegone is another para-menthane monoterpenoids and is found in several plants such as Catnip (Nepeta cataria) and Pennyroyal (Mentha piperita) and has a pleasant smell like that of not only Pennyroyal, Horse Mint (Mentha longifolia) and Peppermint but also of Camphor! It too is used in flavouring, cosmetics and perfumery. It is reported to be toxic to rats and is also the most effective of three insecticides which occur in many species of mint, Mentha.
trans-IsoPulegone is yet another para-menthane monoterpenoids; the other menthanes (ortho-menthane and meta-menthane) are much rarer.
CarvotanAcetone (or at least the (R)- stereoisomer of it) (aka CyproSterone Acetate or Androcur ) is found in the cells of humans where it performs some function unknown to your Author, as he is not a biologist. It belongs to a class of compounds called Menthane monoterpenoids. CarvotanAcetone not only occurs in Corn Mint, but also in Dill and Lovage
Carvone exists in two different stereoisiomers which smell completely different to each other. The first, (R)-Carvone is the one found in Spearmint and Corn Mint and smells of peppermint; whereas (S)-Carvone is found in Caraway and smells accordingly.
With animals (and all other creatures) being constructed from chiral molecules, it is then perhaps no surprise that another chiral molecule (Carvone in this instance), smells completely differently depending upon which chiral form, (R)-Carvone, or (S)-Carvone, is presented to the smell sensors. This is not a unique occurrence, many molecules work completely differently in humans (and other creatures) depending on the exact stereoisometric form present. Sometimes one stereoisometric form will work as intended whilst the other form is toxic.
|