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
Phenylarsonic acid was first prepared by Michaelis and Loenser. X-ray crystallography indicates that the molecules are connected by hydrogen-bonds consistent with short distance of 2.5 Å separating the oxygen atoms. The arsenic center is tetrahedral. Several derivatives of phenylarsonic acid have been used as additives for animal feeds. These include 4-hydroxy-3-nitrobenzenearsonic acid (3-NHPAA, or Roxarsone), "p"-arsanilic acid ("p"-ASA), 4-nitrophenylarsonic acid (4-NPAA), and "p"-ureidophenylarsonic acid ("p"-UPAA). Phenylarsonic acid Phenylarsonic acid is the chemical compound with the formula CHAsO(OH), commonly abbreviated PhAsOH. This colourless solid is an organic derivative of arsenic acid, AsO(OH), where one OH group has been replaced by a phenyl group.