抄録
Condensation of o-phthaldehydic acid and glycine anhydride in the presence of acetic anhydride and sodium acetate results in the formation of 3, 6-bis (o-carboxybenzal) dioxopioperazine (II), with 3, 6-diphthalidyldioxopiperazine (I), as a by-product. The chief condensate (II) decomposes into isocarbostyril-3-carboxylic acid when heated with sodium hydroxide and also forms this acid when boiled with hydriodic acid and red phosphorus, instead of the double bond alone being reduced. The by-product (I) decomposes into o-toluic acid and glycine when treated with hydriodic acid and red phosphorus and into isocarbostyril-3-carboxylic acid with sodium hydroxide. The same condensation of m-and p-phthalaldehydic acid as in the case of the ortho-compound results in the respective formation of bis (m-and p-carboxybenzal) dioxopiperazine which form m-and p-carboxyphenylalanine on being treated with hydriodic acid and red phosphorus.
