(3R,4S)-6-hydroxy-3,4,5-trimethyl-8-oxo-4,8-dihydro-3H-isochromene-7-carboxylic acid; 3R,4S)-8-hydroxy-3,4,5-trimethyl-6-oxo-4,6-dihydro-3H-isochromene-7-carboxylic acid;(3R-trans)-4,6-dihydro-8-hydroxy-3,4,5-trimethyl-6-oxo-3H-2-benzopyran-7-carboxylic acid;3,4-Dihydro-8-hydroxy-3,4,5-trimethyl-6H-6-oxobenzo(c)pyran-7-carboxylic acid; 3r,4s)-4,6-dihydro-8-hydroxy-3,4,5-trimethyl-6-oxo-3h-2-benzopyran-7-carbox;(3R,4S)-4,6-Dihydro-8-hydroxy-3,4,5-trimethyl-6-oxo-3H-2-benzopyran-7-carboxylic acid
