28917-43-3Relevant articles and documents
Allosteric Guest Binding in Chiral Zirconium(IV) Double Decker Porphyrin Cages
Bruekers, Jeroen P. J.,Hellinghuizen, Matthijs A.,Vanthuyne, Nicolas,Tinnemans, Paul,Gilissen, Pieter J.,Buma, Wybren Jan,Naubron, Jean-Valère,Crassous, Jeanne,Elemans, Johannes A. A. W.,Nolte, Roeland J. M.
, p. 607 - 617 (2021)
Chiral zirconium(IV) double cage sandwich complex Zr(1)2 has been synthesized in one step from porphyrin cage H21. Zr(1)2 was obtained as a racemate, which was resolved by HPLC and the enantiomers were isolated in >99.5 % ee. Their absolute configurations were assigned on the basis of X-ray crystallography and circular dichroism spectroscopy. Vibrational circular dichroism (VCD) experiments on the enantiomers of Zr(1)2 revealed that the chirality around the zirconium center is propagated throughout the whole cage structure. The axial conformational chirality of the double cage complex displayed a VCD fingerprint similar to the one observed previously for a related chiral cage compound with planar and point chirality. Zr(1)2 shows fluorescence, which is quenched when viologen guests bind in its cavities. The binding of viologen and dihydroxybenzene derivatives in the two cavities of Zr(1)2 occurs with negative allostery, the cooperativity factors α (=4 K2/K1) being as low as 0.0076 for the binding of N,N’-dimethylviologen. These allosteric effects are attributed to a pinching of the second cavity as a result of guest binding in the first cavity.
Synthesis of alternating polystyrene/poly(ethyleneoxide) branched polymacromonomers
Deimede, Valadoula,Kallitsis, Joannis K.
, p. 467 - 473 (2002)
Newly designed PS/PEO alternating branched polymacromonomers have been obtained by polycondensation of α-dicarboxy-functionalized polystyrene and α-dihydroxy-functionalized polyethyleneoxide. 4-[3,5-Bis-(methoxycarbonyl)phenoxymethyl]benzyl bromide was used as atom-transfer radical polymerization (ATRP) initiator for the synthesis of α-dicarboxy functionalized polystyrenes. These macromonomers possess low polydispersities and molecular weights in the range of 7000 to 100000, as proved by gel permeation chromatography (GPC) and 1H NMR. α-Dihydroxy functionalized polyethyleneoxide (PEO) was synthesized by treatment of monofunctionalized PEO with 3,5-bis(benzyloxy)benzoyl chloride. Polycondensation of the α-dicarboxy PS with the α-dihydroxy PEO in solution or in bulk resulted in alternating PS/PEO polymacromonomers, which were effectively purified from the unreacted macromonomers and characterized by using 1H NMR, GPC, thermal analysis, and optical microscopy. Light-scattering measurements in organic solvents like THF or dioxane have shown that these polymacromonomers form stable micelles.
Biological Characterization, Mechanistic Investigation and Structure-Activity Relationships of Chemically Stable TLR2 Antagonists
Bermudez, Marcel,Grabowski, Maria,Murgueitio, Manuela S.,Rademann, J?rg,Rudolf, Thomas,Tiemann, Markus,Varga, Péter,Weindl, Günther,Wolber, Gerhard
, (2020/06/08)
Toll-like receptors (TLRs) build the first barrier in the innate immune response and therefore represent promising targets for the modulation of inflammatory processes. Recently, the pyrogallol-containing TLR2 antagonists CU-CPT22 and MMG-11 were reported; however, their 1,2,3-triphenol motif renders them highly susceptible to oxidation and excludes them from use in extended experiments under aerobic conditions. Therefore, we have developed a set of novel TLR2 antagonists (1–9) based on the systematic variation of substructures, linker elements, and the hydrogen-bonding pattern of the pyrogallol precursors by using chemically robust building blocks. The novel series of chemically stable and synthetically accessible TLR2 antagonists (1–9) was pharmacologically characterized, and the potential binding modes of the active compounds were evaluated structurally. Our results provide new insights into structure-activity relationships and allow rationalization of structural binding characteristics. Moreover, they support the hypothesis that this class of TLR ligands bind solely to TLR2 and do not directly interact with TLR1 or TLR6 of the functional heterodimer. The most active compound from this series (6), is chemically stable, nontoxic, TLR2-selective, and shows a similar activity with regard to the pyrogallol starting points, thus indicating the variability of the hydrogen bonding pattern.
Synthesis and comparative structure-activity study of carbohydrate-based phenolic compounds as α-glucosidase inhibitors and antioxidants
MacHida, Shota,Mukai, Saki,Kono, Rina,Funato, Megumi,Saito, Hiroaki,Uchiyama, Taketo
, (2019/12/04)
Twenty-one natural and unnatural phenolic compounds containing a carbohydrate moiety were synthesized and their structure-activity relationship (SAR) was evaluated for α-glucosidase inhibition and antioxidative activity. Varying the position of the galloyl unit on the 1,5-anhydro -D-glucitol (1,5-AG) core resulted in changes in the α-glucosidase inhibitory activity and notably, particularly strong activity was demonstrated when the galloyl unit was present at the C-2 position. Furthermore, increasing the number of the galloyl units significantly affected the α-glucosidase inhibition, and 2,3,4,6-tetra-galloyl-1,5-AG (54) and 2,3,4,6-tetra-galloyl-d-glucopyranose (61) exhibited excellent activities, which were more than 13-fold higher than the α-glucosidase inhibitory activity of acertannin (37). Moreover, a comparative structure-activity study suggested that a hemiacetal hydroxyl functionality in the carbohydrate core and a biaryl bond of the 4,6-O-hexahydroxydiphenoyl (HHDP) group, which are components of ellagitannins including tellimagrandin I, are not necessary for the α-glucosidase inhibitory activity. Lastly, the antioxidant activity increased proportionally with the number of galloyl units.
Synthesis, structure activity relationship and in vitro anti-influenza virus activity of novel polyphenol-pentacyclic triterpene conjugates
Li, Haiwei,Li, Man,Xu, Renyang,Wang, Shouxin,Zhang, Yongmin,Zhang, Lihe,Zhou, Demin,Xiao, Sulong
, p. 560 - 568 (2019/01/03)
It is urgently necessary to develop more effective anti-influenza agents due to the continuous emergence of drug-resistant strains of influenza virus. Our earlier studies have identified that certain pentacyclic triterpene derivatives are effective inhibitors of influenza virus infection. In the present study, a series of C-28 modified pentacyclic triterpene derivatives via conjugation with a series of polyphenols were synthesized, and their antiviral activities against influenza A/WSN/33 (H1N1) virus in MDCK (Madin-Darby canine kidney) cells were evaluated. Four compounds 23m, 23o, 23q and 23s displayed robust anti-influenza potency with averaged IC50 values at the low-micromole level, surpassing the potency of oseltamivir. In addition, the in vitro cytotoxic activity of the four conjugates against MDCK cells showed no toxicity at 100 μM. Further mechanism studies of compound 23s, one of the best representative conjugates with IC50 value of 5.80 μM and a selective index (SI) value of over 17.2, by hemagglutination inhibition (HI), surface plasmon resonance and molecular modeling indicated that this conjugate bound tightly to the viral envelope hemagglutinin (KD = 15.6 μM), thus blocking the invasion of influenza viruses into host cells.
Dendritic architectures by orthogonal thiol-maleimide "click" and furan-maleimide dynamic covalent chemistries
Frayne, Stephen H.,Stolz, Robert M.,Northrop, Brian H.
supporting information, p. 7878 - 7883 (2019/09/06)
A set of dendrons and dendrimers is synthesized divergently using an orthogonal combination of kinetically-driven thiol-maleimide "click" chemistry and thermodynamically reversible furan-maleimide cycloaddition/retrocycloaddition reactions. Growth is controlled by taking advantage of the selective thiol-ene addition of thiols to the electron withdrawn alkene of maleimide in the presence of electron rich alkene of oxanorbornene. Subsequent activation of growing dendrons/dendrimers requires only heat to induce the dynamic covalent liberation of peripheral furan protecting groups. The methodology introduced provides a new route to multifunctional dendrimers that could, in principle, be synthesized by introducing different branched monomers at any stage of dendrimer growth, allowing dendrimer architectures and properties to be better tailored to their intended applications.
NON-PEPTIDE OXYTOCIN RECEPTOR AGONISTS
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Page/Page column 31; 32, (2018/07/05)
Disclosed herein are compounds according to Formula I; a pharmaceutical composition including, consisting essentially of, or consisting of: a pharmaceutically acceptable compound of Formula I and a pharmaceutically acceptable carrier, diluent, or excipient; the use of compounds of Formula I in the preparation of a medicament; and a method including administering a pharmaceutical compositions comprising the compound of Formula I to a patient. The compounds, compositions, use, and methods are directed to the treatment of neurological, psychiatric disorders which are characterised by a fundamental disruption of social behaviour, and substance use disorders.
Discovery of KLS-13019, a Cannabidiol-Derived Neuroprotective Agent, with Improved Potency, Safety, and Permeability
Kinney, William A.,McDonnell, Mark E.,Zhong, Hua Marlon,Liu, Chaomin,Yang, Lanyi,Ling, Wei,Qian, Tao,Chen, Yu,Cai, Zhijie,Petkanas, Dean,Brenneman, Douglas E.
, p. 424 - 428 (2016/05/19)
Cannabidiol is the nonpsychoactive natural component of C. sativa that has been shown to be neuroprotective in multiple animal models. Our interest is to advance a therapeutic candidate for the orphan indication hepatic encephalopathy (HE). HE is a serious neurological disorder that occurs in patients with cirrhosis or liver failure. Although cannabidiol is effective in models of HE, it has limitations in terms of safety and oral bioavailability. Herein, we describe a series of side chain modified resorcinols that were designed for greater hydrophilicity and "drug likeness", while varying hydrogen bond donors, acceptors, architecture, basicity, neutrality, acidity, and polar surface area within the pendent group. Our primary screen evaluated the ability of the test agents to prevent damage to hippocampal neurons induced by ammonium acetate and ethanol at clinically relevant concentrations. Notably, KLS-13019 was 50-fold more potent and >400-fold safer than cannabidiol and exhibited an in vitro profile consistent with improved oral bioavailability.
Benzoic hydroxamate-based iron complexes as model compounds for humic substances: Synthesis, characterization and algal growth experiments
Orlowska, Ewelina,Roller, Alexander,Wiesinger, Hubert,Pignitter, Marc,Jirsa, Franz,Krachler, Regina,Kandioller, Wolfgang,Keppler, Bernhard K.
, p. 40238 - 40249 (2016/05/24)
A series of monomeric and dimeric FeIII complexes bearing benzoic hydroxamates as O,O-chelates has been prepared and characterized by elemental analysis, IR spectroscopy, UV-Vis spectroscopy, electrospray ionization mass spectrometry (ESI-MS), cyclic voltammetry, EPR spectroscopy and for some examples by X-ray diffraction analysis. The stability of the synthesized complexes in pure water and seawater was monitored over 24 h by means of UV-Vis spectrometry. The ability to release iron from the synthesized model complexes has been investigated with algae growth experiments.
Effect of the bulkiness of the end functional amide groups on the optical, gelation, and morphological properties of oligo(p-phenylenevinylene) π-gelators
Babu, Sukumaran Santhosh,Praveen, Vakayil K.,Kartha, Kalathil K.,Mahesh, Sankarapillai,Ajayaghosh, Ayyappanpillai
supporting information, p. 1830 - 1840 (2014/07/08)
Herein, we describe the role of end functional groups in the self-assembly of amide-functionalized oligo(p-phenylenevinylene) (OPV) gelators with different end-groups. The interplay between hydrogen-bonding and π-stacking interactions was controlled by the bulkiness of the end functional groups, thereby resulting in aggregates of different types, which led to the gelation of a wide range of solvents. The variable-temperature UV/Vis absorption and fluorescence spectroscopic features of gelators with small end-groups revealed the formation of 1D H-type aggregates in CHCl3. However, under fast cooling in toluene, 1D H-type aggregates were formed, whereas slow cooling resulted in 2D H-type aggregates. OPV amide with bulky dendritic end-group formed hydrogen-bonded random aggregates in toluene and a morphology transition from vesicles into fibrous aggregates was observed in THF. Interestingly, the presence of bulky end-group enhanced fluorescence in the xerogel state and aggregation in polar solvents. The difference between the aggregation properties of OPV amides with small and bulky end-groups allowed the preparation of self-assembled structures with distinct morphological and optical features. Buying in bulk: OPV amides with small end-groups self-assemble into 2D/1D aggregates in toluene and 1D aggregates in CHCl3. Bulky end-groups impede fluorescence quenching in the self-assembled state by blocking π-stacking and facilitate morphological transition in THF.
