作者:M. Parameswara Reddy、G. S. Krishna Rao
DOI:10.1039/p19810002662
日期:——
(2) to acrylonitrile gives a ketonitrile (3), which on Wolff–Kishner reduction is reduced and hyrolysed in situ to 4,5-bis-p-methoxyphenylpentanoic acid (4). Cyclodehydration of (4) with polyphosphoric acid, followed by borohydride reduction and dehydration furnishes di-O-methylsequirin D (1b) which affords on demethylation sequirin D (1a) in an overall yield from (2) of 60%. The key synthon (4) has also
描述了天然存在的降冰片聚糖sequirin D(1a)的高产率六步合成。将脱氧香豆素(2)迈克尔加成到丙烯腈中可得到酮腈(3),在Wolff–Kishner上还原可还原并原位水解为4,5-双-对-甲氧基苯基戊酸(4)。用多磷酸对(4)进行环脱氢,然后进行硼氢化物还原和脱水,得到二-O-甲基倍半胱氨酸D(1b),其从(2)的总产率为60%,而将Sequirin D(1a)脱甲基。关键合成子(4)也已通过其他三种途径制备。