Second, delta-1-pyrroline and delta-1-piperideine, the autocyclized products of putrescine and cadaverine deamination using diamine oxidase, delta-1-piperideine-6-carboxylate and delta-1-pyrroline-5-carboxylate, endogenous metabolites elevated in antiquitin deficiency and Type II hyperprolinemia respectively, fuse with oABA generating triple-aromatic ring dihydroquinazoline structures with absorption peaks between 430 and 460 nm [20, 35]. Here, AOC1 is linked to pyridoxine-dependent epilepsy.