50334-39-9Relevant academic research and scientific papers
An Annulation Approach to the Synthesis of Pseudoguaianolide Sequiterpene Lactones. Total Syntheses of dl-Confertin and dl-Aromatin
Schultz, Arthur G.,Motyka, Linda A.,Plummer, Mark
, p. 1056 - 1064 (1986)
Annulation of 2-methyl-1,3-cyclopentanedione with 4-(halomethyl)-5-(1-oxopropyl)-3-furancarboxylic esters 6a or 6b provides the fully assembled tricyclic framework, 1, of the cytotoxic pseudoguaianolide sequiterpene lactones.Dienedione 1 has been used to construct (+/-)-confertin (2) and (+/-)-aromatin (3).Experiments relevant to a total synthesis of the more complex helenanolides (e.g., the fastigilins, 4) also are discussed.
Regiochemical Control in the Conjugate Addition of Dithianylidene Anions: Total Syntheses of (+-)-Aromatin and (+-)-Confertin
Ziegler, Frederick E.,Fang, Jim-Min
, p. 825 - 827 (1981)
The lithium anion of the dithiane of (E)-2-methyl-2-butenal has been shown to undergo a highly regioselective Michael addition-alkylation sequence.Subsequent stereoselective transformations of the derived adduct have culminated in syntheses of the pseudoguaianolides (+-)-aromatin and (+-)-confertin.
Allylsilane-Based Annulations. Direct Stereoselective Syntheses of (+/-)-Graveolide and (+/-)-Aromaticin
Majetich, George,Song, Jee-Seop,Leigh, Alistair J.,Condon, Stephen M.
, p. 1030 - 1037 (2007/10/02)
An allylsilane-based annulation was used to construct a functionalized perhydroazulene.The C(1), C(5), and C(10) stereocenters, characteristic of the helenanolides, were established using a reductive alkylation strategy.Stereoselective syntheses of the pseudoguaianolides graveolide and aromaticin were achieved.
Enantioselective Conjugate Addition Greatly Improves the Synthesis of (+)-Confertin
Quinkert, Gerhard,Mueller, Thomas,Koeniger, Andreas,Schultheis, Oliver,Sickenberger, Birgitt,Duerner, Gerd
, p. 3469 - 3472 (2007/10/02)
The five-membered ring building blocks 2+3 are enantioselectively produced by conjugate addition of a chiral ligand-modified organocuprate to 2-methylcyclopent-2-enone (1) (chemical yield: 88percent; e.e.: 88percent) and successfully converted in a multi-step sequence, after final enantioselection by recrystallization of an appropriate intermediate, into the pseudoguaianolide (+)-confertin (5).- Key Words: enantioselective conjugate addition; chiral ligand-modified organocuprates; total synthesis of (+)-confertin
Total Synthesis of the Pseudoguaianolide (+)-Confertin
Quinkert, Gerhard,Schmalz, Hans-Guenther,Walzer, Egon,Gross, Stefan,Kowalczyk-Przewloka, Teresa,et al.
, p. 283 - 316 (2007/10/02)
The first total synthesis of the pseudoguaianolide (+)-confertin (1) begins with the preparation of the enantiomerically pure cyclopropane derivative 6b and its stereospecific ring expansion furnishing the five-membered ring A-building block 8a.The AB ketone 21d is produced by intermolecular Michael addition, Lewis acid catalyzed intramolecular hetero-ene reaction, and a pair of oxidation/reduction reactions.Fusion of the heterocyclic five-membered ring and α-methylenation of the ABC intermediate 35c is accomplished by well-known technology.The structure of essential synthetic intermediates has been determined by 2D-NMR, CD spectroscopy, or single crystal X-ray analysis.The whole synthesis starts from α-chloroacetone and reaches the target compound 1 after 22 steps.
TOTAL SYNTHESIS OF PSEUDOGUAIANOLIDES III. (+/-)-AROMATIN
Lansbury, Peter T.,Vacca, Joseph P.
, p. 2797 - 2804 (2007/10/02)
(+/-)-Aromatin (5), has been assembled from 2-methyl-1,3-cyclopentanedione in a linear synthesis characterized by high regio- and stereoselectivity at all stages.Several contributions to organosynthetic methodology are featured.
