使用电荷中性分子受体选择性提取碱金属盐形式的硫酸盐是超分子化学的圣旨之一。本文中,我们首次描述了具有冠醚位点的基于方胺的离子对受体,该位点能够从水相到有机相中提取硫酸钾(缺少冠醚单元的类似的单位阴离子受体缺乏这种能力)。1 H NMR,UV-vis,DOSY-NMR,DLS和MS实验以及固态单晶结构提供了在受体与硫酸钾相互作用后形成超分子核-壳状组装体的证据。相反,一价钾盐的存在促进了简单的1:1络合物的形成。与4:1组件不同,1:1 1种复合物难溶于有机介质。利用此功能克服了霍夫迈斯特偏倚,并可以通过亲脂性硝酸根阴离子选择性提取极亲水的硫酸根,这在定量AES和离子色谱测量中得到了明确证明。受体结构的简单修饰导致“裸眼”光学传感器能够在SLE和LLE条件下选择性检测硫酸盐。
Squaramide-Catalyzed Michael Addition as a Key Step for the Direct Synthesis of GABAergic Drugs
作者:Radovan Šebesta、Eva Veverková、Stanislav Bilka、Rastislav Baran
DOI:10.1055/s-0035-1560420
日期:——
Enantioselective organocatalytic Michaeladditions serve as the key step in syntheses of chiral drugs based on γ-aminobutyric acid. The applicability of various squaramide catalysts for these Michael-type reactions has been assessed. Very good results in terms both activity and enantioselectivity were obtained in the Michaeladdition of dimethyl malonate to β-nitrostyrenes. On the other hand, a complementary
squaramides were prepared in a straightforward manner and investigated as organocatalysts. The reaction protocol is operationally simple to execute and proceeds with up to 76% enantiomeric excess. Several conditions, additives, catalysts, and substrates have been investigated. The best results were observed with 3-((3,5-bis(trifluoromethyl)phenyl)amino)-4-(((1R,2R)-2-(dipentylamino)cyclohexyl)amino)-cyclobut-3-ene-1
Catalytic asymmetric conjugate addition of various α-mercaptoketones to α,β-unsaturated N-acylated oxazolidin-2-ones with bifunctional organocatalyst
作者:Bo-Liang Zhao、Da-Ming Du
DOI:10.1039/c4ra02400a
日期:——
catalysed enantioselectiveconjugateMichaeladdition reaction of various α-mercaptoketones to α,β-unsaturatedN-acylated oxazolidinones under mild reaction conditions has been developed. This catalytic reaction afforded the corresponding adducts in good yields with high enantioselectivities (up to 92% ee). This is the first example of organocatalysed sulfa-Michael addition using various α-mercaptoketones
TRIAMINOPYRIMIDINE CYCLOBUTENEDIONE DERIVATIVES USED AS PHOSPHATASE CDC25 INHIBITORS
申请人:Liberatore Anne-Marie
公开号:US20100173910A1
公开(公告)日:2010-07-08
The present invention relates to triaminopyrimidine derivatives of formula (I)
where Y, R3, W, R4a, R5a, R4b, R5b, n and m are variable. These compounds have CDC25 phosphatase-inhibiting activity and can therefore be used as drugs in diseases in which CDC25 phosphatases are involved. The invention also relates to pharmaceutical compositions containing said products and methods of using the drug.
作者:Katherine I. Taylor、Jordan S. Ho、Hallie O. Trial、Alan W. Carter、Laura L. Kiessling
DOI:10.1021/jacs.2c05691
日期:2023.11.22
Probes that covalently label protein targets facilitate the identification of ligand-binding sites. Lysine residues are prevalent in the proteome, making them attractive substrates for covalent probes. However, identifying electrophiles that undergo amine-specific, regioselective reactions with bindingsite lysine residues is challenging. Squarates can engage in two sequential conjugate addition–elimination