Names of plant chemicals decluttered.
(Images: Chaulmoogric and Hydnocarpic acids, Chaulmoogra)
Similar to the names of the plants which are based on the name of a person, story or character, the trivial/non-scientific names of phytochemicals (plant chemicals) also are based on a source plant or some other feature. The technical (Scientific-IUPAC name)names are too cumbersome to remember and therefore trivial names are given to them. For example a flavone is technically “2-phenylchromen-4-one (2-phenyl-1-benzopyran-4-one)” and cholesterol is “(3S,8S,9S,10R,13R,14S,17R)-10,13-dimethyl-17-[(2R)-6-methylheptan-2-yl]-2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-3-ol” which are impossible to remember for an experienced chemist also. Therefore there are few easy ways to name and remember the common names of every compound.
1. Names based on the source plant.
a. Oleic acid is a fatty acid obtained from Olea plant (Olive) and therefore based on the source plant. When chemists got a fatty acid similar to Oleic acid (having one more double bond) from Linseed (Linum), they named it linoleic acid (meaning oleic acid from Linseed). But when they got one another fatty acid having an additional double bond from linseed the named it Linolenic acid (indicating an additional olefinic bond to Linoleic acid. The oil from castor is Ricinoleic acid (from Ricinus). A steroid obtained from olive oil is oleanolic acid. Chaulmoogric acid and Hydnocarpic acid are from Chaulmoogra (Hydnocarpus wightiana)
b. Sorbitol is a sugar alcohol obtained first from Sorbus (Rosaceae)
c. Allicin is a sulphur containing compound from garlic (Allium)
d. Glycyrrhizin is a saponin from Liquorice (Glycyrrhiza)
e. Arecaine, arecaidine and arecolidine are the alkaloids from betel nut (Areca)
f. Colchicine is an alkaloid from Colchicum.
g. Menthol and thymol are monoterpenes obtained from from Mentha (peppermint) and Thymus (Thyme)
h.Azadirachtin and quassin are bitter principles from Azadirachta (Neem) and Quassia respectively
i. Lycopene is a carotene from tomato (Lycopersicum)
j. Quercetin and Kaempferol are flavonols from Quercus (cork tree) and Kaempferia respectively
k. Apigenin and luteolin are flavones from Apium and Reseda luteola respectively
l. Caffeine from Coffea (Coffee)
m. Stevioside from Stevia
n. Curcumin and gingerols from Turmeric (Curcuma) and ginger.
2. Based on the properties or source materials
a. Emetine is alkaloid causing vomiting.
b. Glucose because it is sweet (Glu-sweet)
c. Fructose because it is obtained from fruits (Fructs-fruit)
d. Xylose because it is a wood sugar (Xylo- wood)
e. Gallic acid from leaf galls
f. Cyanidin because it is colored red (Cyano-blue/dark blue)
g. Miraculin, a sweet protein which is intensely sweet.
h. Hypoglycine is an amino acid which is hypoglycemic (reducing sugar in body)
i. Dulcitol is due to the sweet taste (dulcis= sweet)
3. . Based on the compound from which it is produced
a. Diosgenin is the non-sugar component of saponin, Dioscin
b. Sapogenins are the aglycones (non-sugar part) of saponins.
These guide lines will ease naming of a new compound, if you find one!!!!.
P.S. This is to give a general idea of deriving names of phytochemicals, so that it will be easier to remember them and to pronounce them properly. There are more than 2,00,000 (two lakhs) of compounds from plants (plant metabolome) and most of them are named similarly.
Mammen Daniel
