1-hydroxy-3,5,6-trimethoxy-xanthone (IIIb), 1,5-dihydroxy-3,6-dimethoxyxanthone (XV) and 0,0-dimethylphloracetophenone (VIIa) gave both ortho and para rearrangement products in each case, and led to the synthesis of dihydroisojacareubin (IIa, 3′ and 4′ = 2H), and alvaxanthone trimethyl ether (XXb).
1-羟基-3,5,6-
三甲氧基-
蒽酮(IIIb),1,5-二羟基-3,6-二甲氧基
黄酮(XV)和0,0-二甲基邻苯
二甲酮的3',3'-
二甲基烯丙基醚的Claisen重排(VIIa)在每种情况下均给出邻位和对位重排产物,并导致合成二氢异雅加瑞宾(IIa,3'和4'= 2H)和
硫杂
蒽酮三
甲醚(XXb)。