Piperonal, also known as heliotropin, is a white or colorless, crystalline solid; it is an arenecarbaldehyde that is 1,3-benzodioxole substituted by a formyl substituent at position 5. It is an organic compound commonly found in flavors and fragrances. The molecule has structural connections with other aromatic aldehydes like benzaldehyde and vanillin. It was isolated in Piper nigrum.

Piperonal has a role as a plant metabolite, a fragrance, and an insect repellent. It exists in a variety of essential oils, but concentrations are small. It occurs naturally in various plants; dill, vanilla, violet flowers, and black pepper are some examples. It forms white crystals (mp 37°C) with a sweet, floral, slightly spicy, heliotrope-like odor. This substance is used by consumers, by professional workers (widespread uses), in formulation or re-packing and at industrial sites.

Piperonal is an impurity of Tadalafil (T004500). Synthesis from the latter chemical is accomplished through a condensation reaction with glyoxylic acid followed by cleaving the resulting α-hydroxy acid with an oxidizer. Although there is no strict correlation between leads to the laboratory and potential efficacy within the field, materials like insecticides found to be effective within the laboratory are found to be equally effective within the field. Synthesis from catechol requires a further step, Williamson ether synthesis using dichloromethane.

Piperonal is metabolized to piperonylic acid which might be converted to a glycine conjugate or to an alanine conjugate or a glutamine conjugate. It is often employed in the synthesis of some pharmaceutical drugs including tadalafil, L-DOPA, and atrasentan. If piperonal is released to the environment, it’ll be dampened within the air. It’s going to be counteracted by sunlight. It’ll not go into the air from moist soil and water surfaces, but it’s going to go into the air from dry soil.

Piperonal is used in the following products: washing & cleaning products, polishes and waxes, products for air protection, biocides (e.g. disinfectants, products for pest control), cosmetics, and products for personal care and perfumes and fragrances. Piperonal has a floral odor which is commonly described as being similar to that of vanillin or cherry. It is usually used to introduce shades of vanilla or almond to the character of a perfume, typically imparting balsamic, powdery, and floral aspects.

No toxicity in laboratory animals has occurred in most studies after repeated exposure to moderate to high oral doses of piperonal. However, some reports of laboratory animals subjected to high oral doses of piperonal had documented damage to the liver. No adverse effects have been observed in laboratory animals after repeated exposure of the skin to high piperonal doses.


Information Sources:

  1. echa.europa.eu
  2. pubchem.ncbi.nlm.nih.gov
  3. wikipedia