Syntheses of the naturally occurring naphtho[2,3-b]pyran-5,10-quinones α-caryopterone, dihydro-α-caryopterone, and O-methyldihydro-α-caryopterone
Abstract
The title compounds have been prepared by appropriate alkylation of 3-hydroxy-5-methoxy-1,4-napthoquinone, obtained from the adduct (6) derived by addition of 1-methoxycyclohexa-1,3-diene (4) to 2-methoxy-1,4-benzoquinone (5).