37592-53-3Relevant articles and documents
Metal-to-Ligand Ratio-Dependent Chemodivergent Asymmetric Synthesis
Zheng, Min,Gao, Ke,Qin, Haitao,Li, Guigen,Lu, Hongjian
supporting information, p. 22892 - 22899 (2021/09/15)
Chemodivergent asymmetric synthesis was achieved by tuning the metal-to-ligand ratio in an organometallic catalytic system. Using N-(aroyloxy)phthalimide as the precursor of either an oxygen-centered aroyloxy radical or a nitrogen-centered phthalimidyl radical, enantioselective oxocyanation or aminocyanation of alkenes was achieved separately through a dual photoredox and copper catalysis. The metal-to-ligand ratio can exert chemoselective control while retaining the high enantiopurity of divergent products. Both reactions proceed efficiently with catalyst loading as low as 0.2 mol % and can be performed on a gram scale without loss of chemoselectivity or enantioselectivity. Chemodivergent asymmetric 1,5-aminocyanation or 1,5-oxocyanation of vinylcyclopropane can also be realized by this protocol. Mechanistic investigations involving electron paramagnetic resonance (EPR) experiments were performed to shed light on the stereochemical and chemodivergent results.
Design, synthesis and evaluation of biphenyl imidazole analogues as potent antifungal agents
Zhao, Shizhen,Zhao, Liyu,Zhang, Xiangqian,Wei, Peng,Wu, Mengya,Su, Xin,Sun, Bin,Zhao, Dongmei,Cheng, Maosheng
supporting information, p. 2448 - 2451 (2019/07/30)
To further explore the structure activity relationships (SARs) of our previously discovered antifungal lead compound (1), a series of biphenyl imidazole analogues were designed, synthesized and evaluated for their in vitro antifungal activity. Many of the
Design, synthesis and evaluation of benzoheterocycle analogues as potent antifungal agents targeting CYP51
Zhao, Shizhen,Wei, Peng,Wu, Mengya,Zhang, Xiangqian,Zhao, Liyu,Jiang, Xiaolin,Hao, Chenzhou,Su, Xin,Zhao, Dongmei,Cheng, Maosheng
, p. 3242 - 3253 (2018/05/23)
To further enhance the anti-Aspergillus efficacy of our previously discovered antifungal lead compound 1, a series of benzoheterocycle analogues were designed, synthesized and evaluated for their in vitro antifungal activity. The most promising compounds 13s and 14a exhibited excellent antifungal activity against C. albicans, C. neoformans, A. fumigatus and fluconazole-resistant C. albicans strains, that was superior or comparable to those of the reference drugs fluconazole and voriconazole. GC–MS analyses suggested that the novel compound 13s might have a similar mechanism to fluconazole by inhibiting fungal lanosterol 14α-demethylase (CYP51). Furthermore, compounds 13s and 14a exhibited low inhibition profiles for various human cytochrome P450 isoforms as well as excellent blood plasma stability.
The reactions of α-amino acids and α-amino acid esters with high valent transition metal halides: synthesis of coordination complexes, activation processes and stabilization of α-ammonium acylchloride cations
Biancalana, Lorenzo,Bortoluzzi, Marco,Ferretti, Eleonora,Hayatifar, Mohammad,Marchetti, Fabio,Pampaloni, Guido,Zacchini, Stefano
, p. 10158 - 10174 (2017/02/15)
Titanium tetrachloride smoothly reacted with a selection of α-amino acids (aaH) in CH2Cl2 affording yellow to orange solid coordination compounds, 1a-d, in 70-78% yields. The salts [NHEt3][TiCl4(aa)], 2a-b, were obtained from TiCl4/aaH/NEt3 (aa = l-phenylalanine, N,N-dimethylphenylalanine), in 60-65% yields. The complex , 3, was isolated from the reaction of l-proline with NbCl5/NHiPr2, performed in CH2Cl2 at room temperature. The X-ray structure of 3 features a bridging (E)-1,2-bis(3,4-dihydro-2H-pyrrol-5-yl)ethene-1,2-diolate ligand, resulting from the unprecedented C-C coupling between two proline units. Unusually stable α-ammonium acyl chlorides were prepared by the reactions of PCl5/MCln (MCln = NbCl5, WCl6) with l-proline, N,N-dimethylphenylalanine, sarcosine and l-methionine. MX5 (M = Nb, Ta; X = F, Cl) reacted with l-leucine methylester and l-proline ethylester to give ionic coordination compounds, [MX4L2][MX6] (M = Nb, L = Me2CHCH2CH(NH2)CO2Me, X = F, 9; Cl, 11a; M = Nb, X = Cl, , 11c; Ta, 11d), in moderate to good yields. [NbCl5(Me2CHCH2CHNH3CO2Me)][NbCl6], 12, was isolated as a co-product of the reaction of NbCl5 with l-leucine isopropylester, and crystallographically characterized. The reaction of NbCl5 with l-serine isopropylester afforded NbCl3(OCH2CHNHCO2iPr), 13, in 66% yield. The activation of the ester O-R bond was observed in the reactions of l-leucine methyl ester with NbF5 and l-proline ethyl ester with MBr5 (M = Nb, Ta), these reactions proceeding with the release of EtF and EtBr, respectively. All the metal products were characterized by analytical and spectroscopic methods, while DFT calculations were carried out in order to provide insight into the structural and mechanistic aspects.
Discovery of biphenyl imidazole derivatives as potent antifungal agents: Design, synthesis, and structure-activity relationship studies
Zhao, Dongmei,Zhao, Shizhen,Zhao, Liyu,Zhang, Xiangqian,Wei, Peng,Liu, Chunchi,Hao, Chenzhou,Sun, Bin,Su, Xin,Cheng, Maosheng
, p. 750 - 758 (2016/12/28)
Fungal infections have became a serious medical problem due to their high incidence and mortality. We describe the discovery and structure-activity relationships studies (SARs) of a series of novel biphenyl imidazole derivatives with excellent antifungal
Serine side chain-linked peptidomimetic conjugates of cyclic HPMPC and HPMPA: Synthesis and interaction with hPEPT1
Peterson, Larryn W.,Sala-Rabanal, Monica,Krylov, Ivan S.,Serpi, Michaela,Kashemirov, Boris A.,McKenna, Charles E.
experimental part, p. 2349 - 2361 (2011/10/09)
Cidofovir (HPMPC), a broad spectrum antiviral agent, cannot be administered orally due to ionization of its phosphonic acid group at physiological pH. One prodrug approach involves conversion to the cyclic form (cHPMPC, 1) and esterification by the side chain hydroxyl group of a peptidomimetic serine. Transport studies in a rat model have shown enhanced levels of total cidofovir species in the plasma after oral dosing with l-Val-l-Ser-OMe cHPMPC, 2a. To explore the possibility that 2a and its three l/d stereoisomers 2b-d undergo active transport mediated by the peptide-specific intestinal transporter PEPT1, we performed radiotracer uptake and electrophysiology experiments applying the two-electrode voltage clamp technique in Xenopus laevis oocytes overexpressing human PEPT1 (hPEPT1, SLC15A1). 2a-d did not induce inward currents, indicating that they are not transported, but the stereoisomers with an l-configuration at the N-terminal valine (2a and 2b) potently inhibited transport of the hPEPT1 substrate glycylsarcosine (Gly-Sar). A "reversed" dipeptide conjugate, l-Ser-l-Ala-OiPr cHPMPC (4), also did not exhibit detectable transport, but completely abolished the Gly-Sar signal, suggesting that affinity of the transporter for these prodrugs is not impaired by a proximate linkage to the drug in the N-terminal amino acid of the dipeptide. Single amino acid conjugates of cHPMPC (3a and 3b) or cHPMPA (5, 6a and 6b) were not transported and only weakly inhibited Gly-Sar transport. The known hPEPT1 prodrug substrate valacyclovir (7) and its l-Val-l-Val dipeptide analogue (8) were used to verify coupled transport by the oocyte model. The results indicate that the previously observed enhanced oral bioavailability of 2a relative to the parent drug is unlikely to be due to active transport by hPEPT1. Syntheses of the novel compounds 2b-d and 3-6 are described, including a convenient solid-phase method to prepare 5, 6a and 6b.
Synthesis and characterization of tailorable biodegradable thermoresponsive methacryloylamide polymers based on l-serine and l-threonine alkyl esters
van Dijk, Maarten,Postma, Tobias M.,Rijkers, Dirk T.S.,Liskamp, Rob M.J.,van Nostrum, Cornelus F.,Hennink, Wim E.
experimental part, p. 2479 - 2485 (2011/10/09)
A series of monomers based on the methyl, ethyl, and isopropyl esters of Nα-(methacryloyl)-serine and -threonine were synthesized, and used in an AIBN-initiated radical polymerization reaction to yield polymers with an Mn ranging between 6.6 and 23.8 kDa. The newly synthesized polymers showed LCST behavior in aqueous solution that could be tailored by subtle variations of the hydrophobicity of the monomers to obtain a broad range of cloud points between 1.5 and >100°C. According to HPLC, the hydrolytic t1/2-values (pH 7.4 at 37°C) of the monomers were found to be 5, 12, and 40 days of the methyl, ethyl, and isopropyl esters, respectively, while the hydrolysis rate of poly[Nα-(methacryloyl)-Ser-OMe] and poly[Nα-(methacryloyl)-Thr-OMe] was found to be significantly lower compared to the corresponding monomers. In order to obtain thermoresponsive nanoparticles, Nα-(methacryloyl)-Thr-OEt was polymerized with (PEG monomethyl ether 5000)2-ABCPA as macroinitiator to yield an amphiphilic block co-polymer, poly[Nα-(methacryloyl)-Thr-OEt]-b-(PEG monomethyl ether 5000), which forms particles of 300 nm at a temperature higher than its cloud point of 24°C. Incubation at physiological conditions induced ester hydrolysis resulting in a destabilization of the particles making these particles suitable for drug delivery purposes.
Synthesis of ester prodrugs of 9-(S)-[3-Hydroxy-2-(phosphonomethoxy)propyl] -2,6-diaminopurine (HPMPDAP) as anti-poxvirus agents
Kre?merová, Marcela,Holy, Antonín,Andrei, Graciela,Pomeisl, Karel,Tichy, Tomá?,B?ehová, Petra,Masojídková, Milena,Dra?ínsky, Martin,Pohl, Radek,Laflamme, Genevieve,Naesens, Lieve,Hui, Hon,Cihlar, Tomas,Neyts, Johan,De Clercq, Erik,Balzarini, Jan,Snoeck, Robert
experimental part, p. 6825 - 6837 (2010/12/30)
9-(S)-[3-Hydroxy-2-(phosphonomethoxy)propyl]-2,6-diaminopurine (HPMPDAP) and its cyclic form were selected for further evaluation as potential drug candidates against poxvirus infections. To increase bioavailability of these compounds, synthesis of their structurally diverse ester prodrugs was carried out: alkoxyalkyl (hexadecyloxypropyl, octadecyloxyethyl, hexadecyloxyethyl), pivaloyloxymethyl (POM), 2,2,2-trifluoroethyl, butylsalicylyl, and prodrugs based on peptidomimetics. Most HPMPDAP prodrugs were synthesized in the form of monoesters as well as the corresponding cyclic phosphonate esters. The activity was evaluated not only against vaccinia virus but also against different herpes viruses. The most potent and active prodrugs against vaccinia virus were the alkoxyalkyl ester derivatives of HPMPDAP, with 50% effective concentrations 400-600-fold lower than those of the parent compound. Prodrugs based on peptidomimetics, the 2,2,2-trifluoroethyl, the POM, and the butylsalicylyl derivatives, were able to inhibit vaccinia virus replication at 50% effective concentrations that were equivalent or ~10-fold lower than those observed for the parent compounds.