2H-1-Benzopyran-3,4-diol, 3,4-dihydro-7-methoxy-2,2-dimethyl-, cis- 3,4-Dihydro-7-methoxy-2,2-dimethyl-2H-1-benzopyran-3,4-diol 73385-34-9 Precocene I-3,4-dihydrodiol