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Synthesis, characterization, and preliminary In vitro cytotoxic evaluation of a series of 2-substituted benzo [d] [1,3] azoles

2021-08-21T19:14:59Z

Title: Synthesis, characterization, and preliminary In vitro cytotoxic evaluation of a series of 2-substituted benzo [d] [1,3] azoles Author: DAVID MORALES_MORALES Contributor: Jorge Ali-Torres Abstract: A series of benzo [d] [1,3] azoles 2-substituted with benzyl- and allyl-sulfanyl groups were synthesized, and their cytotoxic activities were in vitro evaluated against a panel of six human cancer cell lines. The results showed that compounds BTA-1 and BMZ-2 have the best inhibitory effects, compound BMZ-2 being comparable in some cases with the reference drug tamoxifen and exhibiting a low cytotoxic effect against healthy cells. In silico molecular coupling studies at the tamoxifen binding site of ERα and GPER receptors revealed affinity and the possible mode of interaction of both compounds BTA-1 and BMZ-2.

Synthesis of new heterocycle-based selenoamides as potent cytotoxic agents

2021-08-19T19:37:30Z

Title: Synthesis of new heterocycle-based selenoamides as potent cytotoxic agents Author: Jose G Lopez-Cortes Abstract: We report the synthesis of a new series of aryl- and heteroaryl (hydroxy)ethyl selenoamides, in a two-step, one-pot sequence based on the aminolysis/selenative demetalation of Fischer ethoxycarbene complexes, in good to excellent global yields, as small cytotoxic molecules. The molecular structure of a 2-thienyl based selenoamide was confirmed by single-crystal X-Ray diffraction analysis. In vitro analysis against different human cancer (HCT-15, U251 and PC-3) and human T-lymphocyte (MT2) cell lines revealed that the 2-thienyl based selenoamide can be considered a potent and selective compound against the human prostatic adenocarcinoma (PC-3) cell line with an IC50 value of 14.5 μM.

Cyclometalated osmium compounds and beyond: synthesis, properties, applications

2021-08-19T19:18:38Z

Title: Cyclometalated osmium compounds and beyond: synthesis, properties, applications Author: Ronan Le Lagadec Abstract: The synthesis of cyclometalated osmium complexes is usually more complicated than of other transition metals such as Ni, Pd, Pt, Rh, where cyclometalation reactions readily occur via direct activation of C–H bonds. It differs also from their ruthenium analogs. Cyclometalation for osmium usually occurs under more severe conditions, in polar solvents, using specific precursors, stronger acids, or bases. Such requirements expand reaction mechanisms to electrophilic activation, transmetalation, and oxidative addition, often involving C–H bond activations. Osmacycles exhibit specific applications in homogeneous catalysis, photophysics, bioelectrocatalysis and are studied as anticancer agents. This review describes major synthetic pathways to osmacycles and related compounds and discusses their practical applications.

Design of promising heptacoordinated organotin (IV) complexes-PEDOT: PSS-based composite for new-generation optoelectronic devices applications

2021-08-16T17:45:44Z

Title: Design of promising heptacoordinated organotin (IV) complexes-PEDOT: PSS-based composite for new-generation optoelectronic devices applications Author: María Elena Sánchez Vergara Abstract: The synthesis of four mononuclear heptacoordinated organotin (IV) complexes of mixed ligands derived from tridentated Schiff bases and pyrazinecarboxylic acid is reported. This organ- otin (IV) complexes were prepared by using a multicomponent reaction, the reaction proceeds in moderate to good yields (64% to 82%). The complexes were characterized by UV-vis spectroscopy, IR spectroscopy, mass spectrometry, 1H, 13C, and 119Sn nuclear magnetic resonance (NMR) and elemental analysis. The spectroscopic analysis revealed that the tin atom is seven-coordinate in solution and that the carboxyl group acts as monodentate ligand. To determine the effect of the sub- stituent on the optoelectronic properties of the organotin (IV) complexes, thin films were deposited, and the optical bandgap was obtained. A bandgap between 1.88 and 1.98 eV for the pellets and between 1.23 and 1.40 eV for the thin films was obtained. Later, different types of optoelectronic devices with architecture “contacts up/base down” were manufactured and analyzed to compare their electrical behavior. The design was intended to generate a composite based on the synthetized heptacoordinated organotin (IV) complexes embedded on the poly(3,4-ethylenedyoxithiophene)- poly(styrene sulfonate) (PEDOT:PSS). A Schottky curve at low voltages (<1.5 mV) and a current density variation of as much as ~3 × 10−5 A/cm2 at ~1.1 mV was observed. A generated photocur- rent was of approximately 10−7 A and a photoconductivity between 4 × 10−9 and 7 × 10−9 S/cm for all the manufactured structures. The structural modifications on organotin (IV) complexes were focused on the electronic nature of the substituents and their ability to contribute to the electronic delocalization via the π system. The presence of the methyl group, a modest electron donor, or the non-substitution on the aromatic ring, has a reduced effect on the electronic properties of the molecule. However, a strong effect in the electronic properties of the material can be inferred from the presence of electron-withdrawing substituents like chlorine, able to reduce the gap energies.