作者:Barbara Jakob、Hans Gerlach
DOI:10.1002/jlac.199619961226
日期:1996.12
The relative and absolute configuration of (+)-3,12-dihydroxypalmitic acid, a constituent of the Ipomea operculata M. resin, has been determined by synthesis. Dimethyl L-malate was converted via (S)-(+)-1 into the oxirane (S)-(-)-2. Reaction of (-)-2 with the Grignard reagent of 8-benzyloxybromooctane provided (S)-(+)-3 in 84% yield, and this was converted into the aldehyde (S)-(-)-6 via (S)-(-)-4
通过合成已经确定了(+)-3,12-二羟基棕榈酸,即番薯番荔枝菌(Ipomea operculata M.)树脂的组成部分的相对和绝对构型。苹果酸二甲酯通过(S)-(+)- 1转化为环氧乙烷(S)-(-)- 2。(-)- 2与8-苄氧基溴辛烷的格氏试剂反应以84%的收率得到(S)-(+)- 3,并通过(S)转化为醛(S)-(-)- 6 -(-)- 4和(S)-(-)- 5。与乙酸甲酯的烯醇锂反应,得到7和8,可以通过9和10、11和12、13和14转化为内酯(4 S,13 S)-(+)- 15和(4 R,13 S)-(+)- 16最后是甲基酯(3 S,12 S)-(+)- 17和(3 R,12 S)-(+)- 18以及酸(-)- 19和(+)- 20。(+)- 17的赤型构型通过(S)-(-)- 2经由(S)-(+)- 21,(+)- 22,(+)- 23,(+)- 24的格氏试剂和(R)