2045-19-4Relevant academic research and scientific papers
The bivalent ligand approach as a tool for improving the in vitro anti-alzheimer multitarget profile of dimebon
Rosini, Michela,Simoni, Elena,Bartolini, Manuela,Soriano, Elena,Marco-Contelles, Jose,Andrisano, Vincenza,Monti, Barbara,Windisch, Manfred,Hutter-Paier, Birgit,Mcclymont, David W.,Mellor, Ian R.,Bolognesi, Maria Laura
, p. 1276 - 1281 (2013)
Inspired by the concept of bivalent ligands, we prepared a small set of analogues of the drug candidate dimebon. They were shown to inhibit AChE, Aβ42 aggregation, and NMDA receptor activation to a greater extent than dimebon. Some of these compounds also enhanced the survival of chicken neurons under apoptosis-inducing conditions. Copyright
Chiral fluorescence sensor as well as preparation method and application thereof in chiral amino acid recognition
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Paragraph 0030; 0032; 0039-0041, (2021/05/29)
The invention discloses a binaphthol derivative shown as a formula I or a stereoisomer thereof. The binaphthol derivative is obtained by carrying out condensation reaction on a binaphthol derivative with chirality and N,N-bis(2-bromoethyl)aniline and then
Synergetic activation of CO2by the DBU-organocatalyst and amine substrates towards stable carbamate salts for synthesis of oxazolidinones
Chen, Xiao-Chao,Liu, Ye,Lu, Yong,Yao, Yin-Qing,Zhao, Kai-Chun
, p. 7072 - 7082 (2021/11/17)
The development of an efficient methodology to transform CO2 into valuable chemicals has attracted increasing attention concerning the challenging issues of CO2-utilization. Herein, an efficient approach for the preparation of oxazolidinones from CO2, primary (aliphatic/aromatic) amines and 1,2-dichloroethane (or its derivatives) catalyzed by DBU organo-superbase was achieved with yields of 47-97% under mild conditions (80-100 °C, 12 h, 1.0 MPa CO2). Control experiments demonstrated that the formation of an ion-pair carbamate salt intermediate IS-B derived from the reaction of CO2, DBU (catalyst) and an amine (substrate) was the key step for this three-component reaction. The available DBU-amine-CO2 adduct intermediate (like IS-B-2) with fair stability will evolve into the thermodynamically stable product oxazolidinones upon attack of 1,2-dichloroethane (or its derivatives), along with the regeneration of the DBU catalyst. Alternatively, the decomposition of the DBU-aryl amine-CO2 adduct (like IS-B-1) with relatively poor stability also could result in the competitive substitution reaction of 1,2-dichloroethane (or its derivatives) with the aryl amine. This work provides insights into synergetic CO2-activation by the DBU-catalyst and a nucleophilic amine-substrate via the formation of robust carbamate salt intermediates responsible for the final production of oxazolidinones. This journal is
Dual coordination modes of ethylene-linked NP2 ligands in cobalt(II) and nickel(II) iodides
Dong, Qingchen,Rose, Michael J.,Wong, Wai-Yeung,Gray, Harry B.
experimental part, p. 10213 - 10224 (2011/12/01)
Here we report the syntheses and crystal structures of a series of cobalt(II) and nickel(II) complexes derived from RNP2 ligands (where R = OMeBz, HBz, BrBz, Ph) bearing ethylene linkers between a single N and two P donors. The CoII complexes generally adopt a tetrahedral configuration of general formula [(NP2)Co(I) 2], wherein the two phosphorus donors are bound to the metal center but the central N-donor remains unbound. We have found one case of structural isomerism within a single crystal structure. The CoII complex derived from BzNP2 displays dual coordination modes: one in the tetrahedral complex [(BzNP2)Co(I)2]; and the other in a square pyramidal variant, [(BzNP2)Co(I)2]. In contrast, the NiII complexes adopt a square planar geometry in which the P(Et)N(Et)P donors in the ligand backbone are coordinated to the metal center, resulting in cationic species of formula [(RNP2)Ni(I)]+ with iodide as counterion. All NiII complexes exhibit sharp 1H and 31P spectra in the diamagnetic region. The Co II complexes are high-spin (S = 3/2) in the solid state as determined by SQUID measurements from 4 to 300 K. Solution electron paramagnetic resonance (EPR) experiments reveal a high-spin/low-spin CoII equilibrium that is dependent on solvent and ligand substituent.
A near IR di-styryl BODIPY-based ratiometric fluorescent chemosensor for Hg(II)
Atilgan, Serdar,Kutuk, Ilker,Ozdemir, Tugba
supporting information; experimental part, p. 892 - 894 (2010/05/03)
A novel BODIPY-based near-IR emitting probe as a selective and sensitive fluorophore for Hg(II) is synthesized. This versatile BODIPY fluorophore is functionalized for long wavelength emission at the 3 and 5 positions via a condensation reaction in which
Hypoxia-Selective Antitumor Agents. 3. Relationships between Structure and Cytotoxicity against Cultured Tumor Cells for Substituted N,N-Bis(2-chloroethyl)anilines
Palmer, Brian D.,Wilson, William R.,Pullen, Susan M.,Denny, William A.
, p. 112 - 121 (2007/10/02)
A series of aniline mustards with a wide range of electron-donating and -withdrawing substituents in the 3- and 4-positions has been synthesized and evaluated for cytotoxicity in cell culture to examine the potential of using nitro group deactivated nitrogen mustards for the design of novel hypoxia-selective anticancer drugs (Denny, W.A.; Wilson, W.R.J.Med Chem. 1986, 29, 879).Hydrolytic half-lives in tissue culture media, determined by bioassay against a cell line (UV4) defective in the repair of DNA interstrand cross-links showed the expected dependence on the Hammett electronic parameter, ?, varying from 0.13 h for the 4-amino analogue to >100 h for analogues with strongly electron-withdrawing substituents.Cytotoxic potencies in aerobic UV4 cultures showed a similar dependence on ?.This dependence predicted that the 4-nitroaniline mustard would be 7200-fold less potent than its potential six-electron reduction product, the 4-amino compound, in growth inhibition assays using a 1-h drug exposure.The measured differential was much lower (225-fold) because of the instability of the latter compound, but a differential of 17500-fold was observed in the initial rate of killing by using a clonogenic assay.The potential for formation of reactive mustards by reduction to the amine or hydroxylamine was demonstrated by the 4-nitroso compound, which had an aerobic toxicity similar to that of the amine.Although these features confirmed the original rationale, the 3-nitro- and 4-nitroaniline mustards had only minimal hypoxic selectivity against UV cells.Toxicity to hypoxic cells appears to be limited by the low reduction potentials of these compounds and consequent lack of enzymatic nitroreduction.However, this study has demonstrated that nitro groups can be used to latentiate aromatic nitrogen mustards and indicates that examples with higher reduction potentials could provide useful hypoxia-selective therapeutic agents.
