Catalytic asymmetric Friedel–Craftsalkylation is a powerful protocol for constructing a chiral C(sp2)C(sp3) bond. Most previous examples rely on LUMO activation of the electrophiles using chiral catalysts with subsequent attack by electron‐rich arenes. Presented herein is an alternative strategy in which the HOMO of the aromatic π system of 2‐furfuryl ketones is raised through the formation of a formal
Silyl nitronates, nitrile oxides, and derived 2-isoxazolines in organic synthesis. Functionalization of butadiene, a novel route to furans and 2-isoxazolines as an alternative to aldol-type condensations
作者:Nalin B. Das、Kurt B.G. Torssell
DOI:10.1016/s0040-4020(01)91947-7
日期:——
di-addition of silylnitronates and nitrile oxides is a useful procedure for functionalizing butadiene leading to cyano and acyl derivatives. A novel route to 2,5-disubstituted furans is also established. The potential of the method in carbohydrate synthesis is pointed out. The route via 2-isoxazoline is shown to be a useful alternative to aldol-type reactions in organicsynthesis. 15a has been studied by X-ray
A selective oxidative fission of the heterocyclic nucleus of 5-methyl-2-(acylmethyl)furans or 2-(5-methyl-2-furyl)-1,3-dicarbonylcompounds by m-chloroperbenzoic acid allows the easy synthesis of the 3(2H)-furanone system.
Photo-sensitized oxygenation of the furyl diketones (1) affords furan-3(2H)-ones (3) in satisfactory yields, presumably via the intermediate open-chain enetriones (2).
A pharmaceutical preparation containing a 3-(2H)-furanone derivative for prevention and/or treatment of cataracts
申请人:KIKKOMAN CORPORATION
公开号:EP0737476A2
公开(公告)日:1996-10-16
In order to prevent or treat cataracts, present invention features 3(2H)-furanone derivatives having 3(2H)-furanone skeleton as a main structure and/or pharmaceutically acceptable salts thereof, pharmaceutical preparations containing the derivatives and/or the salts thereof, treatment methods of cataracts, and their use. The 3(2H)-furanone derivatives have excellent effects for the prevention and/or treatment of cataracts, for instance, senile cataracts caused by oxidation disorder. Particularly, the pharmaceutical preparations have good effect for the prevention and/or treatment of cataracts when they are administrated as ophtalmics.