Total Synthesis and Biological Activities of (+)- and (−)-Boscialin and Their 1‘-Epimers
作者:Joachim Busch、Yvonne Grether、Dietmar Ochs、Urs Séquin
DOI:10.1021/np970517x
日期:1998.5.1
the natural product, (+)-boscialin [(+)-1], could be obtained via acid-catalyzed epimerization of hydroxyketone 4 to (+)-3. Starting the synthesis with (-)-3 led to (-)-boscialin [(-)-1] with the natural absolute configuration. In addition to (+)- and (-)-boscialin, the corresponding 1'-epimers (+)- and (-)-epiboscialin were also obtained. In vitro assays with (-)-boscialin [(-)-1] and its three stereoisomers
天然(-)-boscialin [(-)-1]最近被描述为各种药用植物的成分之一。为了获得更多用于研究其生物学活性的材料,我们进行了(-)-1及其异构体的合成。从手性结构单元2开始,合成的关键步骤涉及区域选择性还原和亲核加成。天然产物(+)-波西林霉素[(+)-1]的对映异构体可以通过酸催化将羟基酮4异构化为(+)-3而得到。以(-)-3开始合成会生成具有天然绝对构型的(-)-boscialin [(-)-1]。除了(+)-和(-)-波西可林外,还获得了相应的1'-表位(+)-和(-)-表波西林。用(-)-boscialin [(-)-1]及其三种立体异构体进行了体外测定,以测试其对微生物,寄生虫和人成纤维细胞的活性。调查显示出对各种微生物和布鲁氏罗氏锥虫的活性,并且还揭示了对人类癌细胞的细胞毒性。