1H-2-benzopyran, 3,4-dihydro- 3,4-dihydro-1H-isochromene InChI=1/C5H9O2.ClH4O4/c1-5-6-3-2-4-7-5;2-1(3,4)5/h2-4H2,1H3;1-4H/q+1;-