23314-24-1Relevant articles and documents
Supramolecular cross-linked networks via host-guest complexation with cucurbit[8]uril
Appel, Eric A.,Biedermann, Frank,Rauwald, Urs,Jones, Samuel T.,Zayed, Jameel M.,Scherman, Oren A.
, p. 14251 - 14260 (2010)
The ability to finely tune the solution viscosity of an aqueous system is critical in many applications ranging from large-scale fluid-based industrial processes to free-standing hydrogels important in regenerative medicine, controlled drug delivery, and 'green' self-healing materials. Herein we demonstrate the use of the macrocyclic host molecule cucurbit[8]uril (CB[8]) to facilitate reversible cross-linking of multivalent copolymers with high binding constants (Ka > 1011-1012 M-2) leading to a supramolecular hydrogel. Multivalent copolymers were prepared by free radical polymerization techniques and contained either pendant methyl viologen (a good first guest for CB[8]) or naphthoxy derivatives (good second guests for CB[8]). A colorless solution of the two multivalent copolymers bearing first and second guests, respectively, can be transformed into a highly viscous, colored supramolecular hydrogel with the cross-link density being easily controlled through CB[8] addition. Moreover, the cross-links (1:1:1 supramolecular ternary complexes of CB[8]/viologen/naphthoxy) are dynamic and stimuli-responsive, and the material properties can be modulated by temperature or other external stimuli. Rheological characterization of the bulk material properties of these dynamically cross-linked networks provided insight into the kinetics of CB[8] ternary complexation responsible for elastically active cross-linking with a second guest dissociation rate constant (kd) of 1200 s-1 for the ternary complex. These materials exhibited intermediate mechanical properties at 5 wt % in water (plateau modulus = 350-600 Pa and zero-shear viscosity = 5-55 Pa?s), which is complementary to existing supramolecular hydrogels. Additionally, these supramolecular hydrogels exhibited thermal reversibility and subsequent facile modulation of microstructure upon further addition of CB[8] and thermal treatment. The fundamental knowledge gained from the study of these dynamic materials will facilitate progress in the field of smart, self-healing materials, self-assembled hydrogels, and controlled solution viscosity.
Synthesis and Biochemical Evaluation of Noncyclic Nucleotide Exchange Proteins Directly Activated by cAMP 1 (EPAC1) Regulators
Wang, Pingyuan,Luchowska-Stańska, Urszula,Van Basten, Boy,Chen, Haiying,Liu, Zhiqing,Wiejak, Jolanta,Whelan, Padraic,Morgan, David,Lochhead, Emma,Barker, Graeme,Rehmann, Holger,Yarwood, Stephen J.,Zhou, Jia
, p. 5159 - 5184 (2020/06/03)
Exchange proteins directly activated by cAMP (EPAC) play a central role in various biological functions, and activation of the EPAC1 protein has shown potential benefits for the treatment of various human diseases. Herein, we report the synthesis and biochemical evaluation of a series of noncyclic nucleotide EPAC1 activators. Several potent EPAC1 binders were identified including 25g, 25q, 25n, 25u, 25e, and 25f, which promote EPAC1 guanine nucleotide exchange factor activity in vitro. These agonists can also activate EPAC1 protein in cells, where they exhibit excellent selectivity toward EPAC over protein kinase A and G protein-coupled receptors. Moreover, 25e, 25f, 25n, and 25u exhibited improved selectivity toward activation of EPAC1 over EPAC2 in cells. Of these, 25u was found to robustly inhibit IL-6-activated signal transducer and activator of transcription 3 (STAT3) and subsequent induction of the pro-inflammatory vascular cell adhesion molecule 1 (VCAM1) cell-adhesion protein. These novel EPAC1 activators may therefore act as useful pharmacological tools for elucidation of EPAC function and promising drug leads for the treatment of relevant human diseases.
AMINOETHYLATION PROCESS HAVING IMPROVED YIELD OF ARYLOXYALKYLENE AMINE COMPOUNDS AND REDUCED UREA BY-PRODUCTS
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Paragraph 0059, (2014/03/25)
Disclosed is a process for preparing an aryloxyalkylene amine compound via an aminoethylation reaction comprising: a) reacting an aromatic hydroxyl compound in the presence of a basic catalyst with a 2-oxazolidinone compound of the formula II to form an intermediate reaction product; wherein R3 is selected from the group consisting of hydrogen or lower alkyl having 1 to 6 carbon atoms, R4 is selected from the group consisting of hydrogen, straight or branched chain alkyl having from one to six carbon atoms, phenyl, alkaryl, or arylalkyl; and b) reacting the intermediate product of step a) with a polyalkylene polyamine.
