115869-43-7Relevant articles and documents
A concise asymmetric synthesis of (-)- trans -aerangis lactone
Pandey, Rachana,Prakash, Ranjana
, p. 1061 - 1063 (2018)
A concise stereoselective approach to functionalized δ-lactone skeleton from monosilylated ethylene glycol as a starting material and its application to the asymmetric total synthesis of (-)-trans-aerangis lactone have been demonstrated. The synthesis uti
Second-Generation Synthesis of the Northern Fragment of Mandelalide A: Role of π-Stacking on Sharpless Dihydroxylation of cis-Enynes
Ghosh, Ankan,Brueckner, Alexander C.,Cheong, Paul Ha-Yeon,Carter, Rich G.
, p. 9196 - 9214 (2019)
The development of a π-stacking-based approach for increased stereoselectivity in Sharpless asymmetric and diastereomeric dihydroxylation of cis-enynes is disclosed. The use of neighboring, electron-rich benzoate esters proved key to the success of this process. Density functional theory study suggests that the substrate benzoate ester group rigidifies the dihydroxylation transition states by forming a favorable π-stacking interaction in both Major-TS and Minor-TS. The energetic preference for the Major-TS was found in part because of the favorable eclipsing conformation of the alkene substituent as opposed to the disfavored bisecting conformation found in the Minor-TS. The application to a second-generation synthesis of the C15-C24 northern portion of mandelalide A is demonstrated.
Ambruticins: tetrahydropyran ring formation and total synthesis
Bowen, James I.,Crump, Matthew P.,Wang, Luoyi,Willis, Christine L.
, p. 6210 - 6215 (2021/07/28)
The ambruticins are a family of polyketide natural products which exhibit potent antifungal activity. Gene knockout experiments are in accord with the proposal that the tetrahydropyran ring of the ambruticins is formedviathe AmbJ catalysed epoxidation of the unsaturated 3,5-dihydroxy acid, ambruticin J, followed by regioselective cyclisation to ambruticin F. Herein, a convergent approach to the total synthesis of ambruticin J is described as well as model studies involving epoxidation and cyclisations of unsaturated hydroxy esters to give tetrahydropyrans and tetrahydrofurans. The total synthesis involves preparation of three key fragments which were unitedviaa Suzuki-Miyaura cross-coupling and Julia-Kocienski olefination to generate the required carbon framework. Global deprotection to a triol and selective oxidation of the primary alcohol gave, after hydrolysis of the lactone, ambruticin J.
Synthesis of 1,2,3-Triazoles Bearing a 4-Hydroxyisoxazolidine Moiety from 4,5-Unsubstituted 2,3-Dihydroisoxazoles
?imoni?ová, Kristína,?tadániová, Radka,Doháňo?ová, Jana,Fischer, Róbert,Janotka, ?ubo?,Messingerová, Lucia,Moncol, Ján,Sahul?ík, Michal
, (2020/08/03)
A synthetic approach towards new 1,2,3-triazoles bearing the 3-hydroxymethylated 4-hydroxyisoxazolidine moiety has been described. The strategy has relied on dihydroxylation and epoxidation reactions of 4,5-unsubstituted 2,3-dihydroisoxazoles, allowing the introduction of the hydroxy group at the isoxazolidine ring in a trans stereoselective manner with respect to the substituent at C-3 carbon atom. The requisite 5-azidoisoxazolidines have been prepared from activated isoxazolidines possessing a good leaving group at C-5 carbon atom by treatment with trimethylsilyl azide and Lewis acid (isoxazolidinyl benzoates) or with sodium azide (chloroisoxazolidines). The 1,2,3-triazole moiety has been synthesized through copper(I)-catalyzed azide-alkyne cycloaddition.
