459-73-4Relevant articles and documents
An efficient approach to diarylethene-amino acid photochromic fluorescent hybrids
Bren, Vladimir A.,Dubonosov, Alexander D.,Kuzmina, Lyudmila G.,Minkin, Vladimir I.,Podshibyakin, Vitaly А.,Shepelenko, Еvgenii N.,Yu. Karlutova, Olga
, (2021)
An effective approach to the synthesis of diarylethene-amino acid hybrids DE-Gly, DE-AABA and DE-DAA (5a-d - 7-a-d) was developed via condensation of furan-2,5-dione-based diarylethenes (DE) and ethyl esters of glycine (Gly), α-aminobutyric acid (AABA) and D-aspartic acid (DAA) with moderate to good yields. According to X-ray diffraction data, DE-Gly hybrid 5a exists in an antiparallel conformation with a distance of 4.549 ? between the reactive carbon atoms C(1)-C(11), potentially capable of forming a single bond, which is suitable for the conrotatory photocyclization reaction allowed by the Woodward-Hoffman rules. The structures of the obtained compounds were proved by 1H, COZY, HSQC, HMBC and 13C NMR spectroscopy. The hybrids DE-Gly, DE-AABA and DE-DAA absorb at 443–456 nm, which corresponds to their existence in a ring-open form O, and display fluorescence at 531–612 nm. Irradiation with light of 436 nm results in their rearrangement into ring-closed colored nonfluorescent isomers C. Backwards re-opening occurs under the action of visible light (λ > 500 nm). Spectral kinetic investigation of 5a,c revealed that the efficiency of photocyclization, as well as the emission quantum yield, decreases with the growth of solvent polarity. The ring-closed isomer C of sterically hindered 5a (R2 = R3 = Me) is stable at room temperature, whereas for 5c (R3 = H), ring opening readily occurs with the speed increasing with the polarity of the solvent. The internal emission of sterically hindered hybrids 5a, 6a and 7a (R2 = R3 = Me) is reversibly modulated in a binary response with good fatigue resistance under successive irradiation with light of 436 and 540 nm.
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Buckingham et al.
, p. 4173,4174, 4175, 4177 (1973)
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Copper-induced ammonia N-H functionalization
álvarez, María,álvarez, Eleuterio,Fructos, Manuel R.,Urbano, Juan,Pérez, Pedro J.
, p. 14628 - 14633 (2016)
The activation of ammonia has been achieved with the aid of the TpMsCu core (TpMs = hydrotris(3-mesityl-pyrazolyl)borate). Complexes of the general composition TpMsCu(amine) (1-4) including the ammonia adduct TpMsCu(NH3) (1) have been synthesized and fully spectroscopical- and structurally characterized. Coordinated ammonia in 1 has been reacted with Ph3CPF6 yielding TpMsCu(NH2CPh3) (5) as a result of N-H cleavage and N-C bond formation. In a parallel manner the catalytic functionalization of ammonia with ethyl diazoacetate leading to glycinate derivatives has been developed with TpMsCu(THF) as the catalyst, in the first example of this transformation with ammonia and a copper-based system.
Synthesis of some new 5-arylidene-2,4-thiazolidinedione esters
Tshiluka, Ndivhuwo R.,Bvumbi, Mpelegeng V.,Ramaite, Isaiah I.,Mnyakeni-Moleele, Simon S.
, p. 161 - 175 (2021/03/17)
Compounds containing the 1,3-thiazolidine-2,4-dione scaffold are gaining increasing scientific interest as potential interventional agents for a variety of disease states. A four-step synthesis of ethyl-(2-(5-arylidine-2,4- dioxothiazolidin-3-yl)acetyl)glycinates, alaninates, butanoates, valinates and norvalinates is described. The synthesis began by converting 1,3-thiazolidine-2,4-dione into its potassium salt, which was treated with ethyl (2-chloroacetamido)glycinates, alaninates, butanoates, valinates and norvalinates, respectively, to obtain the penultimate products. These products were then subjected to a Knoevenagel condensation reaction with different aldehydes to obtain the desired products in low to excellent yields.
Design, synthesis and biological evaluation of novel 2-(5-aryl-1H-imidazol-1-yl) derivatives as potential inhibitors of the HIV-1 Vpu and host BST-2 protein interaction
Bode, Moira L.,Coyanis, E. Mabel,Mosebi, Salerwe,Njengele, Zikhona,Rashamuse, Thompho J.,Sayed, Yasien
, (2020/02/13)
Novel ethyl 2-(5-aryl-1H-imidazol-1-yl)-acetates 17 and propionates 18, together with their acetic acid 19 and acetohydrazide 20 derivatives, were designed and synthesized using TosMIC chemistry. Biological evaluation of these newly synthesized scaffolds in the HIV-1 Vpu- Host BST-2 ELISA assay identified seven hits (17a, 17b, 17c, 17g, 18a, 20f and 20g) with greater than 50% inhibitory activity. These hits were validated in the HIV-1 Vpu- Host BST-2 AlphaScreen and six of the seven compounds were found to have comparable percentage inhibitory activities to those of the ELISA assay. Compounds 17b and 20g, with consistent percentage inhibitory activities across the two assays, had IC50 values of 11.6 ± 1.1 μM and 17.6 ± 0.9 μM in a dose response AlphaScreen assay. In a cell-based HIV-1 antiviral assay, compound 17b exhibited an EC50 = 6.3 ± 0.7 μM at non-toxic concentrations (CC50 = 184.5 ± 0.8 μM), whereas compound 20g displayed antiviral activity roughly equivalent to its toxicity (CC50 = 159.5 ± 0.9 μM). This data suggests that compound 17b, active in both cell-based and biochemical assays, provides a good starting point for the design of possible lead compounds for prevention of HIV-1 Vpu and host BST-2 protein binding in new anti-HIV therapeutics.
