[(3-BEnzyl-4,8,8-trimethyl-2-oxo-9,10-dihydro-2h,8h-pyrano[2,3-f]chromen-5-yl)oxy]acetic acid 1g

[(3-BEnzyl-4,8,8-trimethyl-2-oxo-9,10-dihydro-2h,8h-pyrano[2,3-f]chromen-5-yl)oxy]acetic acid 1g