Pyrrolothiazolate formed by the Maillard reaction between L-cysteine and D-glucose has a pyrrolothiazole skeleton as a chromophore. We searched for a Maillard pigment having a pyrrolooxazole skeleton formed from l-threonine or L-serine instead of L-cysteine in the presence of L-glucose. As a result, two novel yellow pigments, named pyrrolooxazolates A and B, were isolated from model solutions of the Maillard reaction containing L-threonine and d-glucose, and L-serine and D-glucose, respectively, and identified as (2R,3S,7aS)-2,3,7,7a-tetrahydro-6-hydroxy-2,5,7a-trimethyl-7-oxo-pyrrolo[2,1-b]oxazole-3-calboxylic acid and (3S,7aS)-2,3,7,7a-tetrahydro-6-hydroxy-5,7a-dimethyl-7-oxo-pyrrolo[2,1-b]oxazole-3-calboxylic acid by instrumental analyses. These compounds were pyrrolooxazole derivatives carrying a carboxy group, and showed the absorption maxima at 300-360nm under acidic and neutral conditions and at 320-390nm under alkaline conditions.