1972 年 92 巻 1 号 p. 92-96
Reduction of aristolochic acid (I) with sodium borohydride in diglyme was examined. I was reduced to 9, 10-dihydroaristolochic acid (II) at room temperature in a 80-85% yield, with the formation of a small amount of 3, 4-methylenedioxy-8-methoxyphenanthrene-1-carboxylic acid (VII) as a by-product. On heating at 90-100°, I was reduced to VII exclusively in a 75-80% yield. On the other hand, hydroboration of I at room temperature gave 1-methyl-3, 4-methylenedioxy-8-methoxyphenanthrene (IX) and 3, 4-methylenedioxy-8-methoxy-10-nitrophenanthrene (IV).