(S)-(+)-姜黄烯的立体选择性全合成

利用不对称双羟化反应和Raney镍的原位还原,高对映选择性和高产率地实现了(S)-(+)-α-姜黄烯(1)的立体选择性合成.用MsCl保护化合物7a和7b时,发现了有趣的消除和重排反应,得到对应的二烯化合物8.     

Total synthesis of xanthanolides

The total synthesis and determination of the absolute configuration of (+)- and (−)-sundiversifolide have been achieved via intramolecular acylation and Wittig-lactonization as the key steps. The xanthanolide sesquiterpene lactones, 8-epi-xanthatin (1), dihydroxanthatin (2), and xanthatin (3) were also prepared, starting from a common intermediate derived from the synthesis of sundiversifolide.     

Bisabolane Sesquiterpenes from Ligularia thyrsoidea

Phytochemistry investigation of the whole plants of Ligularia thyrsoidea, has led to the isolation of five new bisabolane sesquiterpenes along with three known compounds. The structures of these new compounds were elucidated by spectroscopic methods and 2D NMR techniques.     

Two New Bisabolane Sesquiterpenes from Ligularia Thyrsoidea

ＩｎＣｈｉｎａ，ｍｏｒｅｔｈａｎ２０Ｌｉｇｕｌａｒｉａｓｐｅｃｉｅｓ（Ｃｏｍｐｏｓｉｔａｅ）ｈａｖｅｂｅｅｎｕｓｅｄｆｏｒｆｏｌｋｍｅｄｉｃｉｎｅｓｗｉｔｈａｎｔｉｂｉｏｔｉｃ，ａｎｔｉｐｈｌｏｇｉｓｔｉｃａｎｄａｎｔｉｔｕｍｏｒａｃｔｉｖｉｔｉｅｓ...     

6-Oxodendrolasinolide的全合成

以香叶醇(2)和异戊烯醇(5)为起始原料, 经过12步反应, 以5.6%的总收率完成了倍半萜内酯6-Oxodendrolasinolide (1)的全合成. 其关键步骤包括乙烯基二噻烷(7)的负离子与烯丙基氯(4a)的区域选择性烷基化反应和Corey's氧化内酯化反应.     

Efficient Total Synthesis of Racemic Bisabolane Sesquiterpenes Curcuphenol and Xanthorrhizol Starting from Substituted Acetophenones

A total synthesis of natural bisabolane sesquiterpenes curcuphenol ( 1 ) and xanthorrhizol ( 2 ) was developed by using the substituted acetophenones 4 and 5 , respectively, as starting materials. The acetyl group of the latter was activated through ethoxycarbonylation to carry out the prenylation, which was performed successfully to give their respective precursors 11a and 11b , and 21 that were converted into the corresponding natural sesquiterpenes 1 and 2 , respectively, over four steps and in high overall yields.     

5α,11-二羟基-2-氧代桉烷-3-烯的全合成

5α，11-二羟基-2-氧代桉烷-3-(5α-Hydroxy—isopterocarpolone，1)是由贾忠建等于1996年从中药南牡蒿中首次分离得到的一种桉烷型倍半萜类天然产物．桉烷型倍半萜类化合物广泛分布于天然植物中，具有较好的昆虫拒食、抑制细胞繁殖和植物生长调节等多种生理活性．天然产物1的合成研究尚未见报道．     

Total synthesis,reactivity, and structural clarification of lindenatriene

The synthesis of lindenatriene (1) and iso-lindenatriene (12) were achieved, along with the des-hydroxy model compounds (10 and 18, respectively), and compared to reported ¹H NMR spectra in the literature (1a and 10a). These comparisons clarify the correct initial assignment of lindenatriene (1) as well as its instability and propensity to isomerize into the more thermodynamically favored iso-lindenatriene (12).     

Enantiospecific synthesis of (+)-hernandulcin

The sesquiterpene (+)-hernandulcin has been enantiospecifically synthesized starting from (−)-neoisopulegol in seven steps and in 25% overall yield.     

The First Total Synthesis of Triprenylquinone and Hydroquinones

Marine natural products have received much attention for their attractive structural features and biological activities1. Since the isolation of the moritoside, about 10 related triprenylquinones and hydroquinones were isolated. Some of these natural products exhibit interesting biological effects including inhibit cell division of fertilized starfish eggs2 and anti-HIV3. Triprenylquinone and hydroquinones 1, 2 and 3 were recently isolated from endemic nudibranch Leminda millecra collected i…     

Asymmetric total synthesis of (+)-curcutetraol and (+)-sydonol

The asymmetric total syntheses of (+)-curcutetraol and (+)-sydonol, phenolic bisabolane-type sesquiterpenoids having chiral tertiary alcohol moiety in the o-position of a phenol, were achieved in high enantiomeric excesses (99% ee). The chiral tertiary benzylic alcohol moiety of these compounds was constructed by an asymmetric synthesis using an easily available chiral aminal, (−)-(2R,5S)-2-methoxycarbonyl-3-phenyl-1,3-diazabicyclo[3.3.0]octane. The absolute configurations of both (+)-curcutetraol and (+)-sydonol have been assumed to be S-configuration based on the stereochemical course of the well established asymmetric synthesis used in the syntheses.     

4R-岩白菜素的合成

岩白菜素为碳苷类化合物,具有广泛的生理活性。本文通过一系列反应,将岩白菜素分子中4位羟基的构型由S转化为R,合成得到其非对映异构体4(R)-岩白菜素,为岩白菜素的衍生化研究提供了新的思路。     

Synthesis of bisabolane sesquiterpenes: a Johnson-Claisen rearrangement approach

<正>Several bisabolane sesquiterpenes,(±)-curcumene,(±)-curcuphenol,(±)-curcudiol and(±)-curcuhydroquinone,have been synthesized in racemic form and fully characterized.The salient characteristic of our approach is that a Johnson-Claisen arrangement was involved as a key step.     

First asymmetric total synthesis of (+)-curcutetraol

The first asymmetric total synthesis of (+)-curcutetraol, a marine phenolic bisabolane-type sesquiterpene, was achieved in eight steps in ca. 50% overall yield. The chiral tertiary benzylic alcohol moiety in the o-position of a phenol was constructed in high optical yield (99% ee) by an asymmetric synthesis using a chiral aminal, (2R,5S)-2-methoxycarbonyl-3-phenyl-1,3-diazabicyclo[3.3.0]octane.     

An Efficient Synthetic Strategy for Introduction of C3‐C4 Double Bond into Eudesmane Skeleton: First Total Synthesis of (+)‐Chrysanthemol

The first enantioselective synthesis of (+)‐chrysanthemol 1 was carried out starting from (+)‐dihydrocarvone in ten steps. In our studies, a facile synthetic strategy has been developed for introduction of C₃‐C₄ double bond into a eudesmane skeleton.     

3，7，11－三甲基－10－氧代十二碳酸的全合成

以香叶醇为起始原料，经８步反应合成了由海藻中分离出的新化合物３，７，１１－三甲基－１０－氧代十二碳酸，总收率为１８．５％，合成的关键步骤是甲基异丙基酮的区域选择性烷基化．     

Total synthesis of pleurolactone

The stereoselective total synthesis of pleurolactone has been accomplished in 7 steps. The key synthetic features were the construction of four contiguous stereocenters using an endo-selective Diels-Alder reaction and high diastereoselective dihydroxylation.