Total Synthesis of (±)Chrysotricine

Chrysotricine1wasisolatedfromtheChineseherbmedicineHedyotiSChrysotricha'anditssthectUrehasbeenestablishedasanew0-carbolinealkaloidwitha2,5-trans-substitutedtetrahydrofuranylgrouPatitsl-positionbyX-raydiffractionandspectralanalysis.PharmaceuticalstUdiesshowedpotentialantitUmoractivity.Theinterestingbiologicalactivityandthechemistryof6-carb0linesmict[JIehaveattiactedconsiderableattentioninrecentyears.InordertostUdythisstrUctUre-activityrelationshiPfurther,wewereillterestedinthedevelopmento…     

The First and Facile Synthesis of (±) Syringaresinol

The first and facile synthesis of (±)syringaresinol was described.     

Total Synthesis of (±)-Nimbonone and (±)-12-Ethyl-13-methoxy- 8,11,13-podocarpatriene

Most diterpenoids exhibit significant bioactivities, such as antidermatophytic, antibact- erial, and antioxidant. Although a large number of aromatic tricyclic diterpenoids have been isolated, there are a few of them having ethyl substituent. The synthesis of this type diterpenoids has been seldom reported. In order to further study the relationship between the structure and bioactivities of the diterpenoid, we extended the diterpene synthesis1,2,3. It is desirable to report herein the syn…     

First Total Synthesis of (±)-13-Hydroxy-8 (14)-abietene

(±)-13-Hydroxy-8 (14)-abietene, a rare alicyclic diterpene possessing an isopropyl group and a hydroxy group at the C-13 position, was isolated from Solidago missouriensis nutt1. Many diterpenes exhibit significant bioactivities, such as antibacterial. As a part of our synthetic studies on the naturally-occurring diterpenes, we are attemping the synthesis of the rare natural compound. To our knowledge no total synthetic work has been reported yet. In order to study the further relationship b…     

(±)-Yaequinolone A2的简洁全合成

由廉价的邻氨基苯甲酸为起始原料经6步反应以27.8%的总产率首次合成了2-喹啉酮类生物碱(±)-yaequinolone A2,关键步骤为MOM保护的α-羟基酰胺进行的高非对映选择性分子内aldol 反应。     

两种新木脂素(±)-Eusiderin E和(±)-Eusiderin F的全合成研究

以焦性没食子酸为原料 ,以克来森重排为关键步骤 ,首次合成了天然产物 (± ) -Eusiderin E和 (± ) -Eusiderin F     

Photolysis of oxygen saturated ethers in the presence of Sn(Ⅱ) or Cu(Ⅱ) salts

Photolysis of diethyl ether-oxygen charge transfer complex in the presence of Sn(Ⅱ)or Cu(Ⅱ)salts gave higher yields of the oxidation products,ethyl acetate,acetaldehyde,ethanol,ethyl formate and methanol compared with those without the salts.In addition,the photolysis of an oxygen saturated te-trahydrofuran(THF)or dibutyl ether solution gave y-butyro-lactone or butanol and butyl butyrate as major products with small amounts of undetermined compounds,respectively.Their yields were also affected by the addition of Cu(Ⅱ)or Sn(Ⅱ)salts.     

Synthesis and Catalytic Activity of Copper(Ⅱ) Resorcylic Acid Nanoparticles

Copper(Ⅱ) resorcylic acid(CuRes) nanoparticles were synthesized by using reactive precipitation method with resorcylic acid and blue copperas as the raw material in a rotating packed bed. The sample obtained was characterized by using X-ray diffraction( XRD), transmission electron microscopy( TEM ), Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analyses (TG), and element analysis. In addition, the catalytic activity of CuRes nanoparticles on the thermal decomposition of nitrocellulose-nitroglycerine (NC-NG) was also determined via DSC.The results show that the spherical nanoparticles with a diameter of 20 nm were obtained in ethanol solution. The peak temperature of the thermal decomposition of NC-NG-CuRes decreases by 3 ℃ compared with that of normal CuRes,and the decomposition enthalpy is increased by 735 J/g, and therefore, it is reasonable to assume that CuRes nanoparticles have a better catalytic activity.     

Facile and Efficient Syntheses of (±)-2,6-Dimethyl-6-hydroxy-2,7-octadienoic Acid and Its Methyl Ester

IntroductionMonoterpenoid acid 7a,which is a componentof some traditional medicines such as Gymnocladuschinensis baillon in a glycoside form[1— 3 ] ,has re-cently been isolated from Artemisia sieberi in Iran ina free form[4] .The structure ofthe compound7a has been es-tablished to be( E) - 2 ,6- dimethyl- 6- hydroxy- 2 ,7-octadienoic acid by chemical and spectroscopic anal-yses.Its methyl ester derivative7b was isolatedfrom the antibacterial extracts of the leaves ofPiper aduncum as well[5]…     

Total Synthesis of (±)-Celaphanol A

Celaphanol A was a diterpene isolated from the stems of Celastrus stephanotifolius1, which have been the subject of continued and growing interest, due to the range of biological activities shown by many members of this family2. Some have been used in traditional medicine3 or as a stimulant4 from ancient times. In order to further study the relationship between the structure and biological activity of the diterpene compound and as an extension of diterpenoid synthesis in our laboratory5, 6, …     

天然产物(±)-Litsenolide C_2的立体选择性合成

含3一烷叉基一4，5一二氢一4一羟基一5一甲基一2－（3H）一吠哺酮（简称AHF）结构的天然产物广泛存在于律科植物中［‘j，该类化合物往往具有高细胞毒性和抗肿瘤等生物活性［’－’1．Litseno－lideC是1972年Ishii等［‘j首次从樟科植物中分离得到的一种AHF，其结构为3一十四烷叉基一4，5一二氢一个羟基一5一甲基一2－（3H）一块哺酮，根据其烷又基构型不同又可分为：（3Z，4a，sp）－LitsenolideC；和（3E，4a，sg）－LitsenolideC。（1）．目前大多数合成LitsenolideC的方法立体选择性较差［’－’j，反应产物多为两种异构体的混…     

大环二萜类化合物的研究——Ⅵ.(±)-Cembrene-A全合成新途径

以香叶基丙酮和香叶醇为起始原料,成功地合成了具有十四碳环结构的大环二萜化合物——(±)-Cembrene-A。其中关键步骤是砜化合物(6)与氯代物(9)的相转移偶联反应、低价钛诱导的二羰基前体化合物(12)的分子内环化偶联反应。此合成路线短,总收率为17％。     

Studies on Macrocyclic Diterpenoids (Ⅵ)——A Novel Synthetic Route to (±)-Cembrene-A

The total synthesis of(土)-cembrene-A, a termite pheromone, was achieved from geranylacetone and geraniol as starting materials. The key steps were the phase transfer catalyzed coupling reaction of sulphone (6) with chloride (9) and the intramolecular macrocyclization of dicarbonyl precursor (12) induced by low valent titanium. The synthetic route was short with anoverall yield of 17%.     

Adsorption and Reaction of CO on Mo(100)-c(2×2)-N Surface Studied by HREELS

Molybdenum nitrides have attracted significant attention recently due to their uniquephysical and chemical properties. Many studies have shown that Mo,N is an activecatalyst for CO hydrogenation. The fundamental understanding concerning the reactionmechanisms over Mo=N. however, is not well established. The powerful surface sciencetechniques may provide an insight into the surface structure and properties of such animportant catalytic material. In previous paper', we described the results o…     

A Novel Total Synthesis of (±)Shikonin

Shikonin 1 was a key component isolated from the traditional Chinese herbal medicine, Zicao(Lithospermum erythrorhizon Sieb.et Zucc), which possesses multiple biological activities1. There have been many synthetic routes to shikonin, however, all these ro…     

螺环倍半萜(±)-α-花柏烯-3-酮的全合成

通过萜品油烯 ( Terpinolene)与 2 ,4-二氧代戊酸甲酯的 de Mayo反应得到 [2 +2 ]光加成产物 ,经反aldol重排 ,再环合成具有螺 [5 ,5 ]十一烷结构的花柏烯基本碳架 ,进而对其官能团进行化学修饰 ,完成了螺环倍半萜 (± ) -α-花柏烯 -3 -酮的全合成 .     

Synthesis of Gingerenone C and 5-Hydroxy-1-(4′-hydroxy-3-methoxyphenyl)-7-(4′′-hydroxyphenyl)-3-heptanone

Diarylheptanoidsconstituteadistinctgroupofmetabolitesofnaturalplantcharacterizedbytwoaromaticringslinkedbyalinearsevenaliphaticchain.Therehavebeenfewreportsonthebiologicalactivitiesofdiarylheptanoids,mostofwhichappearingintheareasofanti-inflammatory,anti-oxidative,superoxidescavengingandanti-hepatotoxiceffects1,2.SomeofthemareusedastraditionalmedicineinAsia3.Compound1and2werefirstlyisolatedfromtherhizomesofZingiberofficalrespectively4,5.Sofarthesynthesisofthesetwocompoundshavenotbeenreportedy…     

A New Synthesis of 1-(ω-Haloalkyl)-Imidazoles

Inconnechonwith0urreeenteffortStowardsthesynthesis0fartificialreceptorsandenzymescontalninginddazoles",itwasnecessarytoprepareaclassofl-(orhaloalkyl)-inddazolesassyntheticpreeursors.The0nlyreportinliteratureislindtedforthepreparationofl-(2-bromoethyl)inddazolebyreactingimidazolefirstwithethylenecarbonate,thenwiththionylbr0nddet0givea24.5%yield'.Therearenogeneralpreparativemethodsforthesecompounds.RecenUy,HorvathreportedasimPlemethodf0rthepreparationofl-substitutedinddazolesfromaHoffmann-type…