Methyl anthranilate, also known as MA, methyl 2-aminobenzoate, or carbomethoxyaniline, is an

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides a ...

anthranilic acid Anthranilic acid is an aromatic acid with the formula C6H4(NH2)(CO2H) and has a sweetish taste. The molecule consists of a benzene ring, ''ortho''-substituted with a carboxylic acid and an amine. As a result of containing both acidic and basic ...

. Its chemical formula is C₈H₉NO₂. It has a strong and fruity grape smell, and one of its key uses is as a flavoring agent.

Chemical properties

It is a colorless to pale yellow liquid with melting point 24 °C and boiling point 256 °C. It has a density of 1.168 g/cm³ at 20 °C. It has a refractive index of 1.583 at 589 nm of wavelength and 20 °C. It shows a light blue-violet

fluorescence Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, tha ...

. It is very slightly soluble in water, and soluble in

ethanol Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a ...

and

propylene glycol Propylene glycol (IUPAC name: propane-1,2-diol) is a viscous, colorless liquid, which is nearly odorless but possesses a faintly sweet taste. Its chemical formula is CH3CH(OH)CH2OH. Containing two alcohol groups, it is classed as a diol. It i ...

. It is insoluble in paraffin oil. It is combustible, with flash point at 104 °C. Pure, it has a fruity grape smell; at 25 ppm it has a sweet, fruity,

Concord grape The Concord grape is a cultivar derived from the grape species '' Vitis labrusca'' (also known as fox grape) that are used as table grapes, wine grapes and juice grapes. They are often used to make grape jelly, grape juice, grape pies, grape-fl ...

-like smell with a musty and berry nuance.The Good Scents Company: Methyl anthranilate
/ref>The Japan Food Chemical Research Foundation
/ref>

Uses

Methyl anthranilate acts as a bird repellent. It is food-grade and can be used to protect corn, sunflowers, rice, fruit, and golf courses. Dimethyl anthranilate (DMA) has a similar effect. It is also used for part of the flavor of grape

Kool-Aid Kool-Aid is an American brand of flavored drink mix owned by Kraft Heinz based in Chicago, Illinois. The powder form was created by Edwin Perkins in 1927 based upon a liquid concentrate called Fruit Smack. History Kool-Aid was invented by ...

. It is used for

flavoring A flavoring (or flavouring), also known as flavor (or flavour) or flavorant, is a food additive used to improve the taste or smell of food. It changes the perceptual impression of food as determined primarily by the chemoreceptors of the gus ...

of candy, soft drinks (e.g.

grape soda Grape drinks (also known as grape soda, grape pop, or purple drink in certain regions of the U.S.) are sweetened drinks with a grape flavor and a deep purple color. They may be carbonated (for example, Fanta) or not (Kool-Aid). ''Grapeade'' first ...

), fruit (e.g. Grāpples), chewing gum, drugs, and nicotine products. Methyl anthranilate both as a component of various natural essential oils and as a synthesised aroma-chemical is used extensively in modern perfumery. It is also used to produce

Schiff base In organic chemistry, a Schiff base (named after Hugo Schiff) is a compound with the general structure ( = alkyl or aryl, but not hydrogen). They can be considered a sub-class of imines, being either secondary ketimines or secondary aldimine ...

s with

aldehyde In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl grou ...

s, many of which are also used in perfumery. In a perfumery context the most common Schiff's Base is known as aurantiol, produced by combining methyl anthranilate and

hydroxycitronellal Hydroxycitronellal (7-hydroxy-3,7-dimethyloctanal) is an odorant used in perfumery. Its molecular formula is C10 H20 O2. It derives from a citronellal. 7-Hydroxy-3, 7-dimethyloctanal, also known as 3, 7-dimethyl-7-hydroxyoctan-1-al or 7-hydrox ...

. In organic synthesis, methyl anthranilate can be used as a source of the highly reactive

aryne Arynes and benzynes are highly reactive species derived from an aromatic ring by removal of two substituents. Arynes are examples of didehydroarenes (1,2-didehydroarenes in this case), although 1,3- and 1,4-didehydroarenes are also known. Arynes a ...

, benzyne. It is obtained by

diazotization Diazonium compounds or diazonium salts are a group of organic compounds sharing a common functional group where R can be any organic group, such as an alkyl or an aryl, and X is an inorganic or organic anion, such as a halide. General propert ...

of the amine group using sodium nitrite which eliminates nitrogen and CO₂ giving benzyne as an intermediate for Diels-Alder addition or other substitution at the ring.

Occurrence

Methyl anthranilate naturally occurs in the

s and other ''

Vitis labrusca ''Vitis labrusca'', the fox grape, is a species of grapevines belonging to the ''Vitis'' genus in the flowering plant family Vitaceae. The vines are native to eastern North America and are the source of many grape cultivars, including Catawba, C ...

'' grapes and hybrids thereof, and in bergamot,

black locust ''Robinia pseudoacacia'', commonly known in its native territory as black locust, is a medium-sized hardwood deciduous tree, belonging to the tribe Robinieae of the legume family Fabaceae. It is endemic to a few small areas of the United States ...

, champak, gardenia, jasmine,

lemon The lemon (''Citrus limon'') is a species of small evergreen trees in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam), Northern Myanmar or China. The tree's ellipsoidal yellow fruit is used for culin ...

mandarin orange The mandarin orange (''Citrus reticulata''), also known as the mandarin or mandarine, is a small citrus tree fruit. Treated as a distinct species of orange, it is usually eaten plain or in fruit salads. Tangerines are a group of orange-colou ...

neroli Neroli oil is an essential oil produced from the blossom of the bitter orange tree (''Citrus aurantium subsp. amara'' or ''Bigaradia''). Its scent is sweet, honeyed and somewhat metallic with green and spicy facets. Orange blossom is also extract ...

oranges An orange is a fruit of various citrus species in the family Rutaceae (see list of plants known as orange); it primarily refers to ''Citrus'' × ''sinensis'', which is also called sweet orange, to distinguish it from the related ''Citrus × ...

rue ''Ruta graveolens'', commonly known as rue, common rue or herb-of-grace, is a species of ''Ruta'' grown as an ornamental plant and herb. It is native to the Balkan Peninsula. It is grown throughout the world in gardens, especially for its bluis ...

oil, strawberry,

tuberose ''Agave amica'', formerly ''Polianthes tuberosa'', the tuberose, is a perennial plant in the family Asparagaceae, subfamily Agavoideae, extracts of which are used as a note in perfumery. Now widely grown as an ornamental plant, the species was o ...

wisteria ''Wisteria'' is a genus of flowering plants in the legume family, Fabaceae (Leguminosae), that includes ten species of woody twining vines that are native to China, Japan, Korea, Vietnam, Southern Canada, the Eastern United States, and north ...

galangal Galangal () is a common name for several tropical rhizomatous spices. Differentiation The word ''galangal'', or its variant ''galanga'' or archaically ''galingale'', can refer in common usage to the aromatic rhizome of any of four plant spec ...

, and

ylang ylang ''Cananga odorata'', known as ylang-ylang ( ) or cananga tree, is a tropical tree that is native to the Philippines, Malaysia, Indonesia, New Guinea, the Solomon Islands, and Queensland, Australia. It is also native to parts of Thailand and Viet ...

. It is also a primary component of the essential apple flavor, along with

ethyl acetate Ethyl acetate ( systematically ethyl ethanoate, commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula , simplified to . This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues ...

and

ethyl butyrate Ethyl butyrate, also known as ethyl butanoate, or butyric ether, is an ester with the chemical formula CH3CH2CH2COOCH2CH3. It is soluble in propylene glycol, paraffin oil, and kerosene. It has a fruity odor, similar to pineapple, and is a key in ...

.Daniele Fraternale, Donata Ricci, Guido Flamini and Giovanna Giomaro. Volatiles Profile of Red Apple from Marche Region (Italy). ''Rec. Nat. Prod.'' (2011), 5:3; 202-207
pdf
/ref>

References

{{Reflist Anthranilates Methyl esters