共查询到20条相似文献,搜索用时 0 毫秒
1.
Gowravaram Sabitha C. Nagendra Reddy Peddabuddi Gopal J.S. Yadav 《Tetrahedron letters》2010,51(43):5736-5739
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
2.
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
3.
Microcarpalide is a strong microfilament disrupting agent. The convergent and stereoselective synthesis of microcarpalide was succeeded via Julia olefination and macrolactonization. 相似文献
4.
Stereoselective and efficient synthesis of respective aminocyclitol moieties 1a and 2a of trehazolin and trehalostatin as hexaacetates 1b and 2b using ring-closing enyne metathesis as the key reaction is described. 相似文献
5.
Cryptomoscatone D2 was synthesized stereoselectively from trans-cinnamaldehyde. The synthesis of the triol frame work relied on the creations of the stereocenters independently by utilizing double Maruoka allylations and Sharpless epoxidation. The lactone moiety was constructed by RCM reaction. 相似文献
6.
R. Sateesh Chandra Kumar 《Tetrahedron letters》2010,51(7):1114-7854
An efficient stereoselective synthesis of dendrobate alkaloid (+)-241D and its C-4 epimer was achieved from the inexpensive, commercially available starting material decanal (10) in an overall yield of 21.9% and 21.1%, respectively. This synthesis utilizes the key steps of Maruoka asymmetric allylation, one-pot epoxidation followed by nucleophilic addition of an organomagnesium reagent (Forsyth’s protocol) and subsequent functional group transformations. 相似文献
7.
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
8.
J.S. Yadav K. Premalatha S.J. Harshavardhan B.V. Subba Reddy 《Tetrahedron letters》2008,49(48):6765-6767
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
9.
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
10.
Xiaoyu Li Xiaozhen JiaoXiaoyu Liu Chengsen TianLiang Dong Yangyang YaoPing Xie 《Tetrahedron letters》2014
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
11.
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
12.
S. Chandrasekhar 《Tetrahedron letters》2007,48(13):2373-2375
An efficient asymmetric synthesis of (+)-tetrahydropseudodistomin is described. The important synthetic features include a Maruoka asymmetric allylation and a Sharpless asymmetric dihydroxylation as key steps for the generation of chirality at C-2, -4, and -5 of the trisubstituted piperidine ring. 相似文献
13.
D.G.S. Sudhakar Ch. Venkata Ramana Reddy Srinivasa Rao Alapati 《Tetrahedron letters》2019,60(37):151027
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
14.
(-)-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
15.
(+)-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
16.
An efficient synthesis of (+)- and (−)-deoxoprosophylline was accomplished from the readily available cis-2-butene-1,4-diol in which the Sharpless asymmetric dihydroxylation was used as the key step. 相似文献
17.
A total synthesis of a proposed structure of xylarolide is described. The key features of the synthesis include Sharpless asymmetric reaction, Wittig olefination, Sharpless asymmetric dihydroxylation, Still-Gennari olefination and Yamaguchi lactonization. The differences in the spectroscopic data of the synthetic and natural product indicate a revision of the assigned structure. 相似文献
18.
A highly stereocontrolled asymmetric total synthesis of epimer of (+)-7-deoxypancratistatin has been achieved from readily available starting materials via unified strategy employing Sharpless asymmetric dihydroxylation, ring closing metathesis, Overman rearrangement, hydrogenolysis and Bischler–Napieralski reaction in 15 purification steps with 15% overall yield. 相似文献
19.
An enantioselective route for the synthesis of key fragment C1-C20 resident in microsclerodermins A and B is described. The route features deoxygenative rearrangement of an hydroxy-alkynoate and a highly enantio- and diastereo-controled iterative dihydroxylation as key reactions, starting from S-(−)-citronellol. 相似文献
20.
Mopuri Sudhakar Reddy Gembali Manikanta Palakodety Radha Krishna 《Tetrahedron letters》2019,60(6):504-506
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