A concise, flexible, and efficient total synthesis of the cytotoxic resin glycosides ipomoeassin B (1) and ipomoeassin E (2) is reported which features the advantages of a novel protecting group strategy employing (Z)-3-dimethyl(phenyl)silyl-2-propenoic acid as cinnamic acid surrogate. The use of this readily available compound allowed the macrocycle of the glycolipids to be formed by ring closing olefin metathesis (RCM) with the aid of the second generation Grubbs carbene complex 12. The resulting E/Z mixture could be selectively hydrogenated using Wilkinson's catalyst [RhCl(PPh3)(3)] without affecting the unsaturated esters in the periphery of the compound, before the C-silyl group was cleaved off with TASF [tris(dimethylamino)sulfonium difluorotrimethylsilicate] under notably mild conditions to release the required cinnamate moiety. Other key steps of the synthesis route comprise the formation of the disaccharide linkage by the trichloroacetimidate method, the formation of the chiral acid segment 19 via a VO(acac)(2)-catalyzed, tert-BuOOH-induced oxidative rearrangement of the optically pure furyl alcohol (-)-15 (Achmatowicz-type reaction), and a reductive cleavage of the 4,6-O-p-methoxybenzylidene acetal in 5 with NaBH3CN and Me3SiCl (TMSCl), the regiochemical course of which was found to be opposite to that previously reported in the literature for sterically less encumbered substrates.
[EN] POLYMERIC IONIC LIQUIDS, METHODS OF MAKING AND METHODS OF USE THEREOF<br/>[FR] LIQUIDES IONIQUES POLYMÈRES, LEURS PROCÉDÉS DE FABRICATION ET LEURS PROCÉDÉS D'UTILISATION
申请人:UNIV TOLEDO
公开号:WO2010017563A1
公开(公告)日:2010-02-11
Polymeric ionic liquids, methods of making and methods of using the same are disclosed.
聚合物离子液体的制备方法和使用方法被披露。
CYCLOPROPANE COMPOUND
申请人:Kao Corporation
公开号:US20190055179A1
公开(公告)日:2019-02-21
Provided are a compound and a fragrance composition that are excellent in harmony with various other fragrance materials and can be blended to impart a natural and fresh floral feeling. The present invention provides a cyclopropane compound represented by Formula (I) and a fragrance composition containing a cyclopropane compound represented by Formula (I):
where R
1
is a methyl group and R
2
is a methyl group, or R
1
is a hydrogen atom and R
2
is an ethyl group.
[EN] CELLULOSIC MATERIAL PRESERVATIVES CONTAINING DISACCHARIDE<br/>[FR] CONSERVATEURS DE MATIÈRE CELLULOSIQUE CONTENANT UN DISACCHARIDE
申请人:EMPIRE TECHNOLOGY DEV LLC
公开号:WO2014018020A1
公开(公告)日:2014-01-30
Articles containing a cellulosic material and at least one polymer containing at least one antimicrobial disaccharide are described, as well as methods for their preparation and use.
描述了含有纤维素材料和至少一种含有至少一种抗菌二糖聚合物的文章,以及它们的制备和使用方法。
High refractive index triazine monomer
申请人:——
公开号:US20020158352A1
公开(公告)日:2002-10-31
The present invention relates to a triazine type monomer, and more particularly, to a 1,3,5-triazine type monomer characterized by having at least one amine group and at least two sulfur atoms, which can be used in manufacturing transparent optical resins having excellent refractive index, surface hardness and absorbance as well as an improved workability and the ability to control a wide range of refractive index according to the change in composition by the monomer itself at room temperature or by polymerizing the monomer with a comonomer in the presence of an organic solvent or an initiator.
The present invention relates to a perfume composition as a raw material of fruity perfumes which has a conventionally unknown peculiar fresh, woody, floral, grassy-leafy nuance and is capable of harmonizing with various perfumes to provide perfume preparations having a more sophisticated odor or scent. The perfume composition of the present invention includes a compound represented by the general formula (I):
wherein R
1
and R
2
are each independently a hydrocarbon group having 1 to 4 carbon atoms; and R
3
is a hydrocarbon group having 2 to 4 carbon atoms.