共查询到20条相似文献,搜索用时 15 毫秒
1.
《Tetrahedron letters》1986,27(34):3967-3970
The title compound has been synthesized beginning with 4-methyl-2-cyclohexen-1-one, using intramolecular hydroxyl-directed reactions to achieve regio- and stereoselectivity at important stages. 相似文献
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Chen ZH Zhang YQ Chen ZM Tu YQ Zhang FM 《Chemical communications (Cambridge, England)》2011,47(6):1836-1838
The first total synthesis of polycyclic Stemona alkaloid maistemonine has been achieved. The efficient approach features a stereoselective intramolecular Schmidt reaction, a ketone-ester condensation, and a Reformatsky reaction. Additionally, another Stemona alkaloid stemonamide was divergently synthesized from a common intermediate. 相似文献
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《Tetrahedron》1986,42(15):4297-4308
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A novel route to (±)-platencin is reported, in which the highly stereoselective alkylative quaternization of a cyclohexenone scaffold via 1,4-diastereoinduction and two radical carbon-carbon bond-forming reactions that involve titanium(III)-mediated cyclization and stannyl-radical-mediated skeletal rearrangement are utilized. 相似文献
6.
《Tetrahedron letters》1987,28(18):2021-2023
The first total synthesis of (±)-sanadaol, a structurally unique marine diterpene, was achieved in a fully stereocontrolled manner. 相似文献
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The total synthesis of (±)-isophellibiline is described. This represents the first synthesis of a member of the nonaromatic homoerythrinan family of alkaloids. The tetracyclic ring system of the natural product was quickly assembled by a strategy that features a retrocycloaddition/cycloaddition reaction of an amidodioxin, an intramolecular Heck reaction and a 6π-electrocyclic ring closure of a dienoic acid. 相似文献
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The total synthesis of (±)-meloscine was completed in a highly stereoselective manner starting from the known 4-(2-aminophenyl)-2,3-dihydro-N-methoxycarbonylpyrrole. The crucial step in this total synthesis involves the efficient construction of the tetracyclic framework of the target natural product by the intramolecular Pauson-Khand reaction. 相似文献
9.
A concise and efficient total synthesis of (±)-cephalosol has been completed (5 steps from known ester 5, 39% overall yield), featuring a Cu(II)-promoted haloisocoumarin formation and sequential Suzuki cross-coupling/intramolecular oxo-Michael addition. 相似文献
10.
《Tetrahedron》1987,43(23):5475-5488
An efficient synthesis of the paniculide A precursor 4 has been achieved beginning with 3-methylglutaric anhydride, and utilizing as the key step an intramolecular Diels-Alder reaction of an acetylenic oxazole to give a 2-methoxyfuran. Acid hydrolysis then provided the requisite butenolide ring characteristic of the paniculides. 相似文献
11.
Novel routes to the naturally occurring indole alkaloid cycloclavine and its unnatural C(5)-epimer are described. Key features include the rapid construction of the heterocyclic core segments by two Diels-Alder reactions. An indole annulation was accomplished by a late-stage intramolecular Diels-Alder furan cycloaddition, and a methylenecyclopropane dienophile was used for a stereoselective intramolecular [4 + 2] cycloaddition to give the cyclopropa[c]indoline building block present in cycloclavine. 相似文献
12.
XS Xu ZW Li YJ Zhang XS Peng HN Wong 《Chemical communications (Cambridge, England)》2012,48(68):8517-8519
The first total synthesis of (±)-pallambins C and D has been accomplished in a linear 38 step reaction from (±)-Wieland-Miescher ketone. The key conversions are featured as follows: a Grob fragmentation-intramolecular aldol cyclization and a thiourea/palladium-catalyzed carbonylative annulation. 相似文献
13.
A total synthesis of (±)-chloranthalactone A was completed. It features substrate-controlled epoxidation of ketone and highly diastereoselective intramolecular cyclopropanation to construct the cis, trans-3/5/6 tricyclic skeleton. 相似文献
14.
The total synthesis of chamobtusin A, the first diterpenoid alkaloid isolated from the whole Pinales, is described. Key features of the synthesis include a stereoselective intramolecular Michael addition to install a key stereocenter and an oxidative manipulation to prepare a 2H-pyrrole ring. 相似文献
15.
A concise first total synthesis of (±) maoecrystal V (1) is reported. The synthesis features a Wessely oxidative dearomatization of a phenol, an intramolecular Diels-Alder reaction, and a Rh-catalyzed O-H bond insertion as key steps. 相似文献
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The bis indole sponge alkaloid dragmacidin E was synthesized in racemic form over 25 steps starting from 7-benzhydroxyindole. Key steps include (a) a Witkop cyclization to facilitate construction of the indole-spanning seven-membered ring and (b) a cyclodehydrative pyrazinone synthesis that unites the two indole-containing sectors. 相似文献
18.
《Tetrahedron》2019,75(52):130774
An efficient total synthesis of scrodentoid A was accomplished starting from a Hagemann's ester and a substituted (2-bromoethyl)benzene. Key reactions in this synthesis include C-alkylation of the Hagemann's ester, 6-endo-Trig cationic cyclization of an enone and Lewis acid promoted isomerization of a cis-fused ketone. 相似文献
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A concise synthesis of (±)-cylindricine C and its C(13)-epimer is described. Starting from 1-octyne, cylindricine C and 13-epi-cylindricine C were prepared in 11% and 15% yields, respectively. The synthesis involves the preparation of the central tricyclic moiety via a radical α-iodoketone carboazidation/bis-reductive amination sequence. Inversion of the stereochemistry at C(13) and C(5) was efficiently achieved on late stage intermediates. 相似文献