393530-60-4Relevant academic research and scientific papers
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.
Total synthesis of Jerangolid A
Hanessian, Stephen,Focken, Thilo,Oza, Rupal
supporting information; experimental part, p. 3172 - 3175 (2010/09/05)
(Figure Presented) The first total synthesis of the antifungal polyketide jerangolid A has been accomplished. Starting with the readily available (R)-Roche ester and (S)-glycidol as chirons, the synthesis involved a highly syn-selective Lewis acid catalyz
Total synthesis of (+)-ambruticin S: Probing the pharmacophoric subunit
Hanessian, Stephen,Focken, Thilo,Mi, Xueling,Oza, Rupal,Chen, Bin,Ritson, Dougal,Beaudegnies, Renaud
experimental part, p. 5601 - 5618 (2010/11/03)
An enantioselective synthesis of the antifungal natural product (+)-ambruticin S has been accomplished starting with the readily available methyl α-d-glucopyranoside, (R)-Roche ester, and (S)-glycidol as chirons, which encompassed seven of the 10 stereogenic centers of the target molecule. The remaining three centers were set by a highly diastereoselective, asymmetric cyclopropanation employing a chiral, nonracemic phosphonamide reagent. Our strategy for the construction of the dihydropyran subunit involved a highly syn-selective Lewis acid catalyzed 6-endo-trig cyclization. Other key steps in the synthesis featured an epoxide opening with a dithiane anion, two efficient phosphonamide-anion based olefinations, and a late-stage C-glycosylation.
Total synthesis of jerangolid D
Pospisil, Jiri,Marko, Istvan E.
, p. 3516 - 3517 (2008/01/01)
A short and convergent synthesis of jerangolid D is described. As key steps, a Blaise reaction is employed to construct the lactone ring, a diastereoselective multicomponent Sakurai condensation leads to the dihydropyran ring, and the skipped diene is ass
A short synthesis of the common dihydropyran segment of the antifungal agents ambruticin and jerangolid A
Lukesh, Julie M.,Donaldson, William A.
, p. 5529 - 5531 (2007/10/03)
The dihydropyranyl segment common to ambruticin and jerangolid A was prepared in six steps (31.7% yield) from (S)-2-benzyloxypropanal via silyloxydiene cyclocondensation, followed by C-glycosidation, and eventual epimerization at C18.
Total synthesis of (+)-ambruticin S
Berberich, Stephen M.,Cherney, Robert J.,Colucci, John,Courillon, Christine,Geraci, Leo S.,Kirkland, Thomas A.,Marx, Matthew A.,Schneider, Matthias F.,Martin, Stephen F.
, p. 6819 - 6832 (2007/10/03)
A convergent total synthesis of the novel antifungal agent ambruticin S (1) has been completed from the assembly of intermediates 18, 33 and 52 that served as the respective A-, B-, and C-ring precursors. The first generation approach to a potential A-ring intermediate eventuated in the synthesis of 9a via a route that featured oxidation of the dihydroxy furan 2 and elaboration of the dihydropyranone 3 derived therefrom. Although 9a served as a precursor of 31E to complete a formal synthesis of 1, there were several inefficiencies associated with the preparation of 9a. A more expedient and efficient route to an A-ring subunit was devised that commenced with the carbohydrate-derived bisacetonide aldehyde 10 and produced 18 in five steps and 46% overall yield. The synthesis of the cyclopropyl sulfone 33 was initiated with the enantioselective cyclopropanation of 19 catalyzed by Rh 2[5(S)-MEPY]4. Ring opening of the resultant lactone 20 followed by a series of refunctionalizations gave 33 in a total of seven steps and 46% yield from 19. Coupling of the A- and B-ring precursors 18 and 33 was then achieved via a modified Julia coupling followed by deprotection and oxidation to furnish the key intermediate 35. The dihydropyran core of the C-ring subunit precursor 49 was formed from the ring closing metathesis of the diene 48, which was prepared in three steps from the known epoxide 45, followed by oxidation. A chelation-controlled addition to the methyl ketone 49 set the stage for a stereoselective [2,3]-Wittig rearrangement that delivered the alcohol 51 that was then transformed in two steps to the sulfone 52. A traditional Julia coupling of 52 and 35 proceeded with excellent stereoselectivity, and subsequent removal of the various protecting groups gave ambruticin S (1). The longest linear sequence was 13 steps and proceeded in 4. 3% overall yield.
