从
金丝桃的根中分离出四种新的
氧杂蒽酮。它们的结构已通过光谱和
化学方法的组合确定为 1,6-dihydroxy-5-methoxy-4',5'-dihydro-4',4',5'-trimethylfurano-(2',3': 3,4)-xanthone (5-O-methyl-2-deprenylrheediaxanthone B), 1,6-dihydroxy-5-methoxy-6',6'-dimethylpyrano-(2',3':3,4)-xanthone (5-O-methylisojacareubin), 1,3,5,6-tetrahydroxy-2-(2',2'-dimethyl-4'-isopropenyl)-cycloopen tanylxanthone (5-O-demethylpaxanthonin) 和 1,3,5 ,6-tetrahydroxy-4-trans-se