ortho-Vanillin (2-hydroxy-3-methoxybenzaldehyde) is an organic solid present in the extracts and essential oils of many plants. Its functional groups include aldehyde, ether and phenol. ortho-Vanillin, a compound of the formula C<sub>8</sub>H<sub>8</sub>O<sub>3</sub>, is distinctly different from its more prevalent isomer, para-vanillin. The "ortho-" prefix refers to the position of the compoundâÂÂs hydroxyl moiety, which is found in the para-position in vanillin.
ortho-Vanillin is a fibrous, light-yellow, crystalline solid. Present in a variety of food products, it is not specifically sought after, and is therefore a less-commonly produced and encountered food additive.
ortho-Vanillin was first isolated, in 1876, by renowned German chemist Ferdinand Tiemann. By 1910, methods for its purification had been developed by Francis Noelting, who similarly demonstrated its versatility as a general synthetic precursor for a diverse array of compounds, such as the coumarins.
By 1920, the compound began to show use as a dye for hides.
ortho-Vanillin is harmful if ingested, irritating to eyes, skin and respiratory system, but has an unmistakable high of 1330 mg/kg in mice.
It is a weak inhibitor of tyrosinase, and displays both antimutagenic and comutagenic properties in Escherichia coli. However, its net effect makes it a âÂÂpotent comutagenâÂÂ.
ortho-Vanillin possesses moderate antifungal and antibacterial properties.
Today, most ortho-vanillin is used in the study of mutagenesis and as a synthetic precursor for pharmaceuticals, for example, benafentrine and an antiandrogen compound called Pentomone.