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1.
The antibiotic (-)-anisomycin was synthesized starting from D-tyrosine using Sharpless asymmetric epoxidation as a key reaction followed by formation and hydrolysis of oxazoline set up all chiral center.  相似文献   

2.
孟银娟  徐亮 《合成化学》2017,25(7):591-595
从易于制备的非手性烯丙醇化合物出发,以经典的的Sharpless不对称环氧化为关键反应构建烯丙仲醇手性中心,共经10步线性步骤以28.6%的总收率首次实现了绣线菊碱C、D全合成路线中BCD三环中间体(-)-4的不对称合成,该合成路线中涉及3个新化合物,其结构经1H NMR, 13C NMR和HR-MS(ESI)表征。  相似文献   

3.
A stereoselective formal total synthesis of borrelidin is described. The synthetic strategy for synthesis of C1-C11 fragment features desymmetrization of Diels-Alder adduct, Sharpless asymmetric epoxidation, regioselective opening of chiral epoxide, and alkylation using Evans chiral auxiliary.  相似文献   

4.
YAO  Hequan  GAO  Yuan  LIU  Peng  XU  Xingxiang 《中国化学》2009,27(10):2025-2030
A stereoselective synthesis of functionalized tetrahydropyran D‐ring of methyl sartortuoate ( 1 ) was achieved starting from geraniol in a high yield. Sharpless asymmetric kinetic resolution, asymmetric dihydroxylation as well as asymmetric epoxidation were applied as key steps to establish all the four stereocenters of the D‐ring.  相似文献   

5.
The synthesis of the styryl lactone Leiocarpin C has been achieved in a highly stereoselective manner using Jacobsen’s kinetic resolution, Sharpless asymmetric epoxidation and Sharpless asymmetric dihydroxylation as key steps. This is the first total synthesis of Leiocarpin C, and thus establishes for the first time the absolute stereochemistry of this natural product.  相似文献   

6.
The first stereoselective total synthesis of antibiotic macrolide Berkeleylactone F is described. The synthetic sequence notably features Sharpless kinetic resolution to access chiral epoxide followed by its regioselective ring-opening reaction, Sharpless asymmetric reaction and ring-closing metathesis.  相似文献   

7.
(-)-Slaframinel,anindolizidincalkal()idisolatedtYomthcfungusR/7i~()c't())IicllegIInlinicolainl965',usuallyinItctsleguminouscattle1tcdsandisrcsponsiblcli>rexcessivesalivationintheanimals.Also,lshowsthep()tcntialityinthetreatmentofdiseasesinvolvingcholinergenicdysfunction,andevenhassomebcneficialeffcctsonruminantdigestivefunction.Muchattentionhasbecndevotedtoitssynthesis'sinccitsabs()lutcstere()chcmistrywasestablishedas(lS,6S,8aS)-l-acetoxy-6-an1in()-ind()lizidine'.Thefirstenantioselectiveto…  相似文献   

8.
The total synthesis of panaginsene has been accomplished in 11 linear steps starting from methyl 3,3-dimethyl-5-oxocyclopent-1-ene-1-carboxylate. The key steps are a Sharpless asymmetric epoxidation and Ti(III)-mediated reductive epoxide opening-radical cyclization to construct the chiral quaternary carbon stereocenter followed by a very challenging HWE olefination reaction on an 1,3-keto aldehyde and a late stage McMurry olefination using low valent titanium to construct the highly constrained angular tetrasubstituted olefin in a five-membered ring.  相似文献   

9.
董汉清  林国强 《中国化学》1998,16(5):458-467
(+)-Preussin (1) and its 5-epimer were synthesized from the divmylcarbmol (3) with Sharpless asymmetric epoxidation of 3 and the oxidative cyclization of 9 with PDC as the key steps  相似文献   

10.
A simple and efficient stereoselective synthesis of naturally occurring pyrrolidine alkaloid, radicamine B has been accomplished in 13 steps from the commercially available starting materials with an overall yield of 9.75%. The synthesis utilizes Sharpless asymmetric epoxidation and Horner-Wadsworth-Emmons (HWE) olefination as key steps.  相似文献   

11.
钼、钨系过氧化物是非常重要的Sharpless烯烃环氧化催化剂,有着非常广泛的工业发展前景。本文综述了钼、钨系过氧化物的种类,结构,合成方法及催化活性,分析了各种钼、钨系过氧化物的特点以及在催化环氧化领域的发展现状。同时,本文还讨论了钼、钨系过氧化物催化烯烃环氧化反应的机理。评述了在催化环氧化领域中两种主要理论——Mimoun机理与Sharpless机理的争论焦点及发展现状,以及计算化学对两种理论中间过渡态的研究进展,并且重点分析了Sharpless机理的过渡态结构。此外,本文还综述了影响钼、钨系过氧化物催化剂反应活性的各种因素以及质子所产生的副反应。最后,本文对应用于催化环氧化领域的钼、钨系过氧化物未来的研究方向提出了建议。  相似文献   

12.
Celia Ribes  Miguel Carda 《Tetrahedron》2006,62(23):5421-5425
A stereoselective synthesis in enantiopure form of the natural anhydrophytosphingosine pachastrissamine (jaspine B), a metabolite isolated from sponges, is described. The chiral epoxide (R)-glycidol was the starting material. Key steps of this synthesis are a Sharpless asymmetric epoxidation, an intramolecular stereospecific epoxide opening mediated by a trichloroacetimidate group, and the formation of a tetrahydrofuran ring via intramolecular nucleophilic displacement.  相似文献   

13.
Synthesis of (2S)-3-(2,4,5-trifluorophenyl)propane-1,2-diol by the Sharpless asymmetric epoxidation reaction has been achieved. 2,4,5-Trifluorobenzaldehyde with methyl 2-(triphenyl-λ5-phosphanylidene)acetate gave methyl (E)-3-(2,4,5-trifluorophenyl)acrylate in 83% yield. The reduction of ester group with DibalH followed by Sharpless asymmetric epoxidation gave ((2R,3R)-3-(2,4,5-trifluorophenyl)oxiran-2-yl)methanol. Pd/C-catalyzed hydrogenation of epoxy alcohol furnished (2S)-3-(2,4,5-trifluorophenyl)propane-1,2-diol with >90% ee and 71% yield.  相似文献   

14.
A practical total synthesis of the natural products (+)-isogalbulin and (+)-galbulin has been achieved in 10 steps from readily available 3-(3,4-dimethoxyphenyl)propanoic acid. The total yields were 12.3% and 12.9%, respectively. The key steps involved Evans asymmetric alkylation, Sharpless asymmetric epoxidation, and a highly regioselective opening of 1-benzyloxy-2,3-epoxides with an organoaluminum ate-complex formed by Me3Al and n-BuLi.  相似文献   

15.
A convergent stereoselective total synthesis of (+)-anamarine via cross-metathesis (CM) protocol starting from 2-butyn-1,4-diol and vinyl lactone is reported. Other key features of the strategy include the use of Sharpless asymmetric epoxidation, Sharpless dihydroxylation, and Red-Al reduction.  相似文献   

16.
An efficient stereoselective total synthesis of balticolid has been accomplished starting from known aldehyde. The key steps involved in this synthesis are Sharpless asymmetric epoxidation, Wittig olefination, alkylation of 1,3-dithiane and Yamaguchi macrolactonization.  相似文献   

17.
First short total synthesis of 5‐epi‐prelactone B has been achieved involving Sharpless asymmetric epoxidation and intramolecular hydride transfer reaction for formation of the aldol product by nonaldol chemistry as the key steps.  相似文献   

18.
A stereoselective total synthesis of oplopandiol, oploxyne A, and (−)-oploxyne B is described. The key reactions include Sharpless asymmetric epoxidation, d-proline catalyzed aminoxylation, Cadiot–Chodkiewicz cross-coupling reaction, m-CPBA induced substrate-controlled stereoselective epoxidation, and Lewis acid catalyzed stereo- and regioselective ring-opening of epoxide.  相似文献   

19.
Stereoselective synthesis of the C21–C40 core segment of caylobolide A has been achieved following a highly efficient convergent strategy. The key reactions featured in the synthesis are Prins cyclization, reductive radical cyclization, Sharpless asymmetric epoxidation and olefin cross metathesis.  相似文献   

20.
A convergent and flexible synthetic route for the synthesis of C3–C12 fragment of iriomoteolide-1a is described. The key steps are: Mannich reaction, Keck asymmetric allylation, Sharpless asymmetric epoxidation and cross-metathesis protocol.  相似文献   

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