Search results for "ZOL"

Halogen bond directionality translates tecton geometry into self-assembled architecture geometry

2013

The structures of halogen-bonded infinite chains involving two diiodoperfluoroalkanes and a bent bis(pyrid-4′-yl)oxadiazole show that the geometry of the pyridyl pendant rings is translated into the angle between the formed halogen bonds.

Synthesis of fluorinated oxadiazoles with gelation and oxygen storage ability

2012

A new family of fluorinated low molecular weight (LMW) gelators has been synthesized through SNAr substitution of 5-polyfluoroaryl-3-perfluoroheptyl-1,2,4-oxadiazoles with glycine ester. The obtained compounds give thermal and pH-sensitive hydrogels or thermo-reversible organogels in DMSO. Oxygen solubility studies showed the ability to maintain high oxygen levels in solution and in gel blend with plate counter agar (PCA).

Contact Sensitizers Specifically Increase MHC Class II Expression on Murine Immature Dendritic Cells

2000

Contact sensitivity is a T-cell-mediated immune disease that can occur when low-molecular-weight chemicals penetrate the skin. In vivo topical application of chemical sensitizers results in morphological modification of Langerhans cells (LC). Moreover, within 18 h, LC increase their major histocompatibility complex (MHC) class II antigens expression and migrate to lymph nodes where they present the sensitizer to T lymphocytes. We wanted to determine if such an effect could also be observed in vitro. However, because of the high genetic diversity encountered in humans, assays were performed with dendritic cells (DC) obtained from a Balb/c mouse strain. The capacity of a strong sensitizer, DN…

Assessment of chronic effects of tebuconazole on survival, reproduction and growth of Daphnia magna after different exposure times

2015

The effect of the fungicide tebuconazole (0.41, 0.52, 0.71 and 1.14mg/L) on survival, reproduction and growth of Daphnia magna organisms was monitored using 14 and 21 days exposure tests. A third experiment was performed by exposing D. magna to the fungicide for 14 days followed by 7 days of recovery (14+7). In order to test fungicide effects on D. magna, parameters as survival, mean whole body length, mean total number of neonates per female, mean number of broods per female, mean brood size per female, time to first brood/reproduction and intrinsic rate of natural increase (r) were used. Reproduction was seriously affected by tebuconazole. All tebuconazole concentrations tested affected t…

A theoretical and experimental study of the racemization process of hexaaza[5]helicenes

2014

A dynamic 1H NMR study, together with DFT calculations, of bis-([1,2,3]triazolo)[1,5-a:5′,1′-k][1,10]phenanthroline 2 has allowed to identify the ring and open forms of a new example of ring/chain tautomerism, as well as their interconversion barriers (ring/ring and ring/open). The barrier of the exchange process between the chain forms and the ring form was found higher than the 'racemization' process in the closed form, so the ring opening does not contribute to the 'racemization'. The di-1,10-methyl and di-1,10-iodo derivatives have been prepared and their properties calculated.

3 He NMR studies on helium-pyrrole, helium-indole, and helium-carbazole systems: a new tool for following chemistry of heterocyclic compounds

2014

The 3He nuclear magnetic shieldings were calculated for free helium atom and He–pyrrole, He–indole, and He–carbazole complexes. Several levels of theory, including Hartree–Fock (HF), Second-order Moller-Plesset Perturbation Theory (MP2), and Density Functional Theory (DFT) (VSXC, M062X, APFD, BHandHLYP, and mPW1PW91), combined with polarization-consistent pcS-2 and aug-pcS-2 basis sets were employed. Gauge-including atomic orbital (GIAO) calculated 3He nuclear magnetic shieldings reproduced accurately previously reported theoretical values for helium gas. 3He nuclear magnetic shieldings and energy changes as result of single helium atom approaching to the five-membered ring of pyrrole, indo…

DESIGN AND SYNTHESIS OF NEW QUINAZOLIN-4(3H)-ONE HYBRIDS AS DUAL INHIBITORS OF TUBULIN AND DIHYDROFOLATE REDUCTASE

New strategies are needed for fighting cancer with the goal to improve efficacy of anti-cancer therapy and to limit the onset of drug resistance. Indeed, cancer cells are able to set cellular mechanisms for survival and multiple pathways support their survival. The inhibition of one pathway may then result in the activation of an alternative pathway. One strategy useful for combatting this phenomenon is represented by multi-target drugs. Herein we will present our work aim at identifying new anticancer compounds, which combine dihydrofolate reductase (DHFR) properties with tubulin inhibition. DHFR is a key enzyme involved in the synthesis of raw material for cell proliferation and the inhib…

Thiazolium-­‐based catalysts for the etherification of benzylic alcohols under solvent-­free conditions

2015

In this work, thiazolium and imidazolium hybrid materials (SBA-15-Thia and SBA-15-Imi) were prepared by grafting the bis-vinylthiazolium or imidazolium salts onto thiol functionalized SBA-15 mesostructured silica. The catalytic activity was tested for the etherification of 1-phenylethanol, in heterogeneous conditions. The reactions were performed under different gas phases and reaction times. The SBA-15-Thia displayed an excellent catalytic performance, also with others benzyl alcohols. This material was successfully used in seven consecutive runs. Further studies were carried out in homogenous conditions. The results obtained allow proving that oxygen play an active role in the reaction pr…

CCDC 606862: Experimental Crystal Structure Determination

2009

Related Article: Hongsheng Liu, C.J.Gomez-Garcia, Jun Peng, Jingquan Sha, Lixia Wang, Yechao Yan|2009|Inorg.Chim.Acta|362|1957|doi:10.1016/j.ica.2008.09.014

Pyridylcarbene formation by thermal decomposition of 7-bromo-3-methyl-[1,2,3]triazolo[1,5-a]pyridine under pressure

2007

7-Bromo-3-methyl-[1,2,3]triazolo[1,5-a]pyridine 1 at 1.7 atm and 100ºC decompose to form a pyridylcarbene intermediate by nitrogen expulsion. The carbene stabilization give 2-bromo-6- vinylpyridine 2, 1-(6-bromopyridin-2-yl)ethanol 3, 1-(6-Bromopyridin-2-yl)ethanone 4, 2- bromo-6-[2-(6-bromopyridin-2-yl)-2-methyl-trans-cyclopropyl]pyridine 5, and 2-bromo-6-[2-(6- bromopyridin-2-yl)-2-methyl-cis-cyclopropyl]pyridine 6. Abarca Gonzalez, Belen, Belen.Abarca@uv.es ; Ballesteros Campos, Rafael, Rafael.Ballesteros@uv.es