the dual electrophilic properties of (2-chloro-2-nitroethenyl)benzenes in a one-pot, formal [3+2] cycloaddition. Using a base (DBU), the desired trisubstituted heterocycles were formed rapidly (10–30 min) in good to excellent yields (51–92 %), and this versatile, metal-free methodology was applied to the synthesis of 2-acyl- and 2-carboalkoxyfurans and furan-2-carboxamides. Additionally, by using 2-ketophosphonate
Compositions And Methods For Enhancing Sialic Acid Levels In Tissue
申请人:The Regents of the University Of California
公开号:US20140315829A1
公开(公告)日:2014-10-23
The invention relates to compositions and methods for increasing sialic acid uptake and/or incorporation into tissue following gastrointestinal ingestion of compositions that contain sialic acid.
Regioselective α-addition of vinylogous α-ketoester enolate in organocatalytic asymmetric Michael reactions: enantioselective synthesis of Rauhut–Currier type products
Catalytic asymmetric α-regioselective Michael additions of vinylogous α-ketoester enolate are described herein. With 0.1-1.0 mol% loadings of a chiral bifunctional organocatalyst, the addition of a deconjugated α-keto ester to a series of nitroolefins, including the challenging β-alkylnitroalkenes, efficiently proceed, providing the Rauhut-Currier type products after isomerization of the terminal double
The present invention is directed to a method for purifying pyruvic acid compounds, which method comprises reacting a pyruvic acid compound of general formula (I):
wherein R1 is an optionally substituted lower alkyl group, a lower alkenyl group, a lower alkynyl group, a cycloalkyl group, an aryl group, or a heterocyclic group, and R2 is a lower alkyl group, with a bisulfite of general formula (II):
MHSO3 (II)
wherein M is NH4 or an alkali metal, to give a bisulfite adduct of the pyruvic acid compound and then decomposing the adduct with an acid. According to the present invention, pyruvic acid compounds can be purified by simple and easy procedures without using purification techniques such as distillation or column chromatography, and the above method is advantageous as a process for the production on an industrial scale.
本发明涉及一种纯化丙酮酸化合物的方法,该方法包括使通式(I)的丙酮酸化合物反应:
其中 R1 是任选取代的低级烷基、低级烯基、低级炔基、环烷基、芳基或杂环基,R2 是低级烷基,与通式(II)的亚硫酸氢盐反应:
MHSO3 (II)
其中 M 为 NH4 或碱金属,以得到丙酮酸化合物的亚硫酸氢盐加合物,然后用酸分解该加合物。根据本发明,丙酮酸化合物可以通过简单易行的程序进行纯化,而无需使用蒸馏或柱层析等纯化技术,上述方法作为一种工业规模的生产工艺是非常有利的。
Membrane computing
申请人:Keinan Ehud
公开号:US20090124506A1
公开(公告)日:2009-05-14
A method of implementation of a P-system in membrane computing comprising: placing three mutually immiscible liquids into a container, such that a first of said liquids provides a barrier between the second and third liquids; providing an initial substrate to at least one of said second and third liquids; and applying a transport rule for said first liquid to allow transport of substrate between said second and said third liquid.