Aspergillic acid acetic acid gives a diketopiperazine. Hydrolysis with HBr yields a mixture of -leucine and -isoleucine. These reaction schemes can be seen below: Aspergillic acid Aspergillic acid is an organic chemical compound with the molecular formula CHNO. It has a pale yellow crystalline appearance. Aspergillic acid is most commonly known as an antibiotic and antifungal agent that is derived from certain strains of the fungus "Aspergillus flavus". In 1940 Edwin C. White and Justina H. Hill discovered that a fungal strain of "Aspergillus flavus" growing in a surface culture on a tryptone-salt was capable of producing a bactericidal filtrate. It has
Sorbic acid Sorbic acid Sorbic acid, or 2,4-hexadienoic acid, is a natural organic compound used as a food preservative. It has the chemical formula CH(CH)COH. It is a colourless solid that is slightly soluble in water and sublimes readily. It was first isolated from the unripe berries of the "Sorbus aucuparia" (rowan tree), hence its name. The traditional route to sorbic acid involves condensation of malonic acid and trans-butenal. It can also be prepared from isomeric hexadienoic acids, which are available via a nickel-catalyzed reaction of allyl chloride, acetylene, and carbon monoxide. The route used commercially, however, is from crotonaldehyde and ketene.