共查询到19条相似文献,搜索用时 62 毫秒
1.
2.
3.
4.
5.
6.
7.
用一种新的简便方法对Verbenachalcone进行全合成, 针对目标物的结构特征, 将其切为2个合成片段, 即化合物4和6, 然后再将2个片段连接. 从对羟基苯甲醛(2)开始经过溴代、乙酰化、Ullmann反应、甲氧甲基化、羟醛缩合、脱保护和催化加氢等7步反应完成了标题化合物的全合成, 总收率为39.1%, 合成的关键步骤是3-溴-4-羟基苯甲醛(3)和香兰素进行的Ullmann反应. 关键中间体与最终产物的化学结构经1H NMR, 13C NMR和ESI-MS等表征确认. 相似文献
8.
对天然产物Isocoene全合成研究方法进行了综述。分析了各合成路线的关键步 骤,并部分讨论了各方法的优缺点。 相似文献
9.
以2,3-二羟基苯甲酸为起始原料,通过酯化、Williams、水解、酰胺化、Robinson-Gabriel环化、脱保护等一系列反应成功合成了gymnothecaoxazoles A,总收率为20.0%,其结构经~1H NMR、~(13)C NMR和HRMS确证。此方法原料廉价易得,反应条件温和,操作简单,为快速制备gymnothecaoxazoles A提供了参考。 相似文献
10.
2′,4-二羟基-4′,6′-二甲氧基-二氢查尔酮的首次全合成 总被引:1,自引:0,他引:1
以2,4,6-三羟基苯乙酮和对羟基苯甲醛为起始原料,经选择性的甲基化,甲氧甲基化,羟醛缩合,还原,脱保护等反应首次完成了2′,4-二羟基-4′,6′-二甲氧基-二氢查尔酮(1)的全合成,总收率40%。1和中间体的结构经1HNMR,IR和MS表征。 相似文献
11.
lsorhapontigenin (I ) is a natural product with many biological activities. M. Linel a/ first isolated it from the traditional Chinese herb, G.parvdoliunl 1. The totalsynthesis of (I ) has been reported' using miting reaction and TMS as the protectinggroup. the reaction gives both E and Z-stilbene, In an attempt to obtain enough sample of(I ) for screening its bioactivities, we have developed an alternative synthetic route toprepare isorhapontigenin through a 7 steps reaction sequence 3. H… 相似文献
12.
13.
Polyhydroxy stilbenes were proved to have many biological activitiesl'2. 'We havereported the total synthesis of tWo natural products-resveratrol (3,5,4'-tTihydroxylstilbene) and isorhapontigenin 3'4 which were first found in a traditional Chinese herb,G.Parvghlium by M. Lins et al. Herein,we want to present the total synthesis of anothernatural hydroxyl stilbene, pinosylvin (3,5-dihydroxy stilbene,10) isolated from this plantand its analog (3,5,3',5'-tetfahydroxy stilbene,9 ). In the synth… 相似文献
14.
BiflavonesareamorecomPlicatedclass0fflavonoids.MostofthemareusefulcomPonentsoftraditionalmedicinetocurediseases.Sincechamaejasminel,anewtoeofbiflavonoidpossessingaC-3/C-3"linkage,wasisolatedfromSteUerachamaejasmaeL.byHuangetal',especiallyafterthebiologicalactivityofani-cancerwasdiscovered',thestUdyof3,3"-biflavonoidshasattfactCdmuchattention.3-5ButtherehasbeennoprogressmentionedonthesynthesisofthiskindofcomPoundsinrecentdecades.AsaresultofoursystematicresearchonthesynthesisofchamaejasInin… 相似文献
15.
Amy B. Dounay Rebecca A. Urbanek Steven F. Sabes Craig J. Forsyth 《Angewandte Chemie (International ed. in English)》1999,38(15):2258-2262
A small change to the structure of okadaic acid ( 1 ), the omission of the single hydroxy group at C7, facilitated substantially the first total synthesis of the derivative 7-deoxyokadaic acid ( 2 ). The conformation of 2 is in agreement with that of 1 and this minimal structural variation has been reported previously to have little effect on the inhibitory activity towards the serine/threonine-specific protein phosphatases PP-1 and PP-2A. 相似文献
16.
17.
《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(24):5956-5968
18.
19.
报道了双木脂素threo-(±)-开环异落叶松脂醇二阿魏酸酯的全合成. 以香草醛为原料, 经过两步Stobbe反应构建木脂素骨架, 然后再用LiAlH4还原、加氢后, 产物经柱层析分离, 得到2个异构体meso-和threo-(±)-开环落叶松脂素; 根据其NMR, IR和HRMS等谱图确认发现, 极性较小的产物threo-(±)-开环落叶松脂素为合成的关键中间体. threo-(±)-开环落叶松脂素与甲氧甲基(MOM)保护的阿魏酸缩合得到目标产物threo-(±)-开环异落叶松脂醇二阿魏酸酯. 合成采用汇聚法, 经11步, 以约8%的总产率得到了目标产物. 该合成方法具有原料价廉易得及操作简便的优点, 并具有一定的实用价值. 相似文献