553668-51-2Relevant academic research and scientific papers
Synthesis, spectroscopic studies and biological evaluation of acridine derivatives: The role of aggregation on the photodynamic efficiency
Felip-León, Carles,Martínez-Arroyo, Olga,Díaz-Oltra, Santiago,Miravet, Juan F.,Apostolova, Nadezda,Galindo, Francisco
, p. 869 - 874 (2018)
Two new photoactive compounds (1 and 2) derived from the 9-amidoacridine chromophore have been synthesized and fully characterized. Their abilities to produce singlet oxygen upon irradiation have been compared. The synthesized compounds show very differen
Insight into the esterase like activity demonstrated by an imidazole appended self-assembling hydrogelator
Singh, Nishant,Conte, Maria P.,Ulijn,Miravet, Juan F.,Escuder, Beatriu
, p. 13213 - 13216 (2015/08/18)
A low molecular weight hydrogelator with a covalently appended imidazole moiety is reported. Capable of percolating water in the pH range of 6 to 8, it proves to be an efficient catalyst upon self-assembly, showing Michaelis-Menten type kinetics. Activities at different pH values correlated with dramatic structural changes were observed. It can hydrolyse p-nitrophenyl acetate (pNPA) as well as inactivated esters, and l and d-phenylalanine methyl esters. The enhanced activity can be related to the conglomeration of catalytic groups upon aggregation resulting in their close proximity and the formation of hydrophobic pockets.
Synthesis and evaluation of pseudopeptidic fluorescence pH probes for acidic cellular organelles: In vivo monitoring of bacterial phagocytosis by multiparametric flow cytometry
Burguete, M. Isabel,Galindo, Francisco,Izquierdo, M. Angeles,O'Connor, Jose-Enrique,Herrera, Guadalupe,Luis, Santiago V.,Vigara, Laura
scheme or table, p. 5967 - 5979 (2011/02/26)
A new family of fluorescent anthracenic pH probes has been synthesized, chemically characterized, and their photophysical properties have been investigated by steady-state and time-resolved fluorescence spectroscopy. The ability of these compounds to monitor pH has been investigated in solution and it was found that molecules 1-12 can act as fluorescent sensors for pH in a range between 4.6 and 6.5. This range corresponds to the pH of acidic organelles in the cell (pH 4.5-6.0) for which a limited number of probes are described. The acid-base behavior of each sensor varies slightly depending on the nature of substituents close to the amines present in the molecules. Thus, the pK a of this family of compounds can be finely tuned by the appropriate selection of the synthetic building blocks at the design stage. To test the potential diagnostic applications of this family of probes, macrocyclic pseudopeptide 2 was used to monitor the phagocytosis of a culture of GFP-labelled bacteria by human monocytic cells U937 using flow cytometry as the analytical tool. It was found that the occurrence of bacterial killing was concomitant with the production of reactive oxygen species and a drop in pH, the latter monitored indirectly by macrocyclic sensor 2, which suggests its potential use for diagnostic purposes. A new family of anthracenic macrocycles has been synthesized that can act as fluorescent probes for pH in the range 4.6-6.5. The pKa values of these compounds can be finely tuned. In flow cytometry experiments, it was found that bacterial killing by human monocytes (U937) occurred with a simultaneous drop in pH, which was monitored by one of the macrocyclic sensors.
New chiral tetraaza ligands for the efficient enantioselective addition of dialkylzinc to aromatic aldehydes
Burguete, M. Isabel,Escorihuela, Jorge,Luis, Santiago V.,Lledós, Agustí,Ujaque, Gregori
, p. 9717 - 9724 (2008/12/22)
A series of chiral tetraaza ligands were studied for the enantioselective addition of dialkylzinc to aldehydes. These bis(amino amide) ligands show high enantioselectivity in the addition of organozincs to aromatic aldehydes. Different structural elements on the ligands seem to play an important role in determining the observed enantioselectivity. Ligand 4b (N,N′-bis(N-l-valinyl)-1,3-diaminopropane, with an aliphatic spacer with 3C atoms) catalyzed the addition of Et2Zn to benzaldehyde, 1-naphtaldehyde, 4-methoxybenzaldehyde, and 4-chlorobenzaldehyde to give the corresponding alcohol products with excellent conversions and selectivities and with enantioselectivities of 99, 97, 98, and 82%, respectively. DFT calculations provide an understanding of the mechanism of the enantioselection process.
Synthetic macrocyclic peptidomimetics as tunable pH probes for the fluorescence imaging of acidic organelles in live cells
Galindo, Francisco,Burguete, M. Isabel,Vigara, Laura,Luis, Santiago V.,Kabir, Nurul,Gavrilovic, Jelena,Russell, David A.
, p. 6504 - 6508 (2007/10/03)
(Chemical Equation Presented) Acid test: Macrocyclic compounds that comprise a 9,10-anthracene subunit linked by a C2-symmetric peptidomimetic chain (see formula) are useful as fluorescent probes in a pH range of biomedical interest. Changes in
Efficient macrocyclization of U-turn preorganized peptidomimetics: The role of intramolecular H-bond and solvophobic effects
Becerril, Jorge,Bolte, Michael,Burguete, M. Isabel,Galindo, Francisco,Garcia-Espana, Enrique,Luis, Santiago V.,Miravet, Juan F.
, p. 6677 - 6686 (2007/10/03)
Simple peptidomimetic molecules derived from amino acids were reacted with meta- and parabis(bromomethyl) benzene in acetonitrile to very efficiently yield macrocyclic structures. The cyclization reaction does not require high dilution techniques and seems to be insensitive to the size of the formed macrocycle. The analysis of data obtained by 1H NMR, single-crystal X-ray diffraction, fluorescence measurements, and molecular mechanics indicate that folded conformations can preorganize the system for an efficient cyclization. The role played by intramolecular hydrogen-bonding and solvophobic effects in the presence of folded conformations is analyzed.
