102-51-2Relevant articles and documents
Quantitative structure-activity relationships on 5-substituted terbenzimidazoles as topoisomerase I poisons and antitumor agents
Kim, Jung Sun,Sun, Qun,Yu, Chiang,Liu, Angela,Liu, Leroy F.,Lavoie, Edmond J.
, p. 163 - 172 (1998)
Several 5-substituted terbenzimidazoles were synthesized and evaluated as mammalian topoisomerase I poisons and for cytotoxicity against a human lymphoblastoma cell line, RPMI-8402. No correlation was observed between topoisomerase I poisoning activity and the Hansch π value or the σ(meta) and σ(para) values associated with each substituent. These data suggest that electronic effects and relative lipophilicity of substituents at the 5-position of these terbenzimidazoles do not have a significant effect upon intrinsic topoisomerase I poisoning activity. There was, however, a good correlation between the relative π values for the various subtituents evaluated and cytotoxic activity. Experimentally determined log P values did not correlate well with either cytotoxicity or π values. Capacity factors (log k') as determined by high pressure liquid chromatography did correlate well with the π values of varied substituents and cytotoxicity. These data indicate that the relative lipophilic activity of substituents at the 5-position of these terbenzimidazoles can strongly influence relative cytotoxic activity.
Poly(2-aminothiazole) as a unique precursor for nitrogen and sulfur co-doped porous carbon: Immobilization of very small gold nanoparticles and its catalytic application
Bide, Yasamin,Nabid, Mohammad Reza,Dastar, Fateme
, p. 63421 - 63428 (2015)
In this contribution, we report two important achievements; first the synthesis of poly(2-aminothiaozle) (P2AT) with a plate structure containing nanoparticles by a rapidly initiated strategy, and second, the one-step synthesis of nitrogen and sulfur co-doped porous carbon materials with unique morphology using P2AT as the source of both N and S, through a simple hydrothermal carbonization reaction. The obtained functional carbon may serve to develop new carbon materials for various applications, especially catalysis, because of the excellent properties, such as straightforward synthesis, defined morphology, high porosity, and heteroatom doping. As one of the most important applications, we used the porous carbon materials as a support for immobilizing gold nanoparticles (AuNPs). Benefiting from the synergistic effects of N and S co-doping, very small AuNPs, and unique structural features, the as-obtained material was demonstrated to be a superior catalyst for reduction of nitrobenzenes.
Synthesis and vasorelaxant evaluation of novel 7-methoxyl-2,3-disubstituted-quinoxaline derivatives
Gao, Wen-Cong,Li, Xun,Ma, Xin,Pang, Pan-Pan,Peng, Li-Chun,Yang, Liang,Zheng, Chang-Bo
, (2021)
An array of novel 7-methoxyl-2,3-disubstituted quinoxaline derivatives was designed, synthesized and their potential antihypertensive activities were examined, in an attempt to discover potent small molecules with vasorelaxant effects. The vasoactivities of these compounds on vascular tone, as well as underlying mechanisms were hereby explored. Results showed that five compounds (7s, 7t, 7v, 7w, 7γ) could induce endothelium-independent relaxation in high extracellular K+- and phenylephrine-precontracted C57 mice aortic rings. These five compounds, unlike other commonly used vasodilators, could slowly but effectively inhibit vasoconstriction.
Synthesis and Pesticidal Activities of New Quinoxalines
Bajsa-Hirschel, Joanna,Cantrell, Charles L.,Duke, Stephen O.,Hua, Xue-Wen,Liu, Xing-Hai,Min, Li-Jing,Tan, Cheng-Xia,Wedge, David E.,Weng, Jian-Quan,Wu, Hong-Ke,Yu, Wei
, p. 7324 - 7332 (2020)
Natural products are a source of many novel compounds with biological activity for the discovery of new pesticides and pharmaceuticals. Quinoxaline is a fused N-heterocycle in many natural products and synthetic compounds, and seven novel quinoxaline derivatives were designed and synthesized via three steps. Pesticidal activities of title quinoxaline derivatives were bioassayed. Most of these compounds had herbicidal, fungicidal, and insecticidal activities. The compounds 2-(6-methoxy-2-oxo-3-phenylquinoxalin-1(2H)-yl)acetonitrile (3f) and 1-allyl-6-methoxy-3-phenylquinoxalin-2(1H)-one (3g) were the most active herbicides and fungicides. Mode-of-action studies indicated that 3f is a protoprophyrinogen oxidase-inhibiting herbicide. Compound 3f also possessed broad-spectrum fungicidal activity against the plant pathogen Colletotrichum species. Some of these compounds also had insecticidal activity. Molecular docking and DFT analysis can potentially be used to design more active compounds.
The Discovery of Quinoxaline-Based Metathesis Catalysts from Synthesis of Grazoprevir (MK-5172)
Williams, Michael J.,Kong, Jongrock,Chung, Cheol K.,Brunskill, Andrew,Campeau, Louis-Charles,McLaughlin, Mark
, p. 1952 - 1955 (2016)
Olefin metathesis (OM) is a reliable and practical synthetic methodology for challenging carbon-carbon bond formations. While existing catalysts can effect many of these transformations, the synthesis and development of new catalysts is essential to increase the application breadth of OM and to achieve improved catalyst activity. The unexpected initial discovery of a novel olefin metathesis catalyst derived from synthetic efforts toward the HCV therapeutic agent grazoprevir (MK-5172) is described. This initial finding has evolved into a class of tunable, shelf-stable ruthenium OM catalysts that are easily prepared and exhibit unique catalytic activity.
Structural factors controlling the self-assembly of columnar liquid crystals
Foster, E. Johan,Jones, R. Bradley,Lavigueur, Christine,Williams, Vance E.
, p. 8569 - 8574 (2006)
A series of disc-shaped molecules were prepared by the condensation of 1,2-diamines with 2,3,6,7-tetrakis(hexyloxy)phenanthrene-9,10-dione to investigate the relationship between changes in molecular structure and the self-assembly of columnar liquid crystalline phases. A comparison of compounds with different core sizes indicated that molecules with larger aromatic cores had a greater propensity to form columnar phases, as did compounds substituted with electron-withdrawing groups. In contrast, molecules with electron-donating substituents were nonmesogenic. The clearing temperature of columnar phases increased linearly with the electron-withdrawing ability of the substituents, as quantified by Hammett σ-values. The observed trends can be rationalized in terms of the strength of π-π interactions between aromatic cores in the liquid crystalline phases and suggest that both electrostatic interactions and dispersion forces play important roles in the self-assembly of these materials.
Synthesis and application of novel styryl dyes derived from 1,4-diethyl-1,2,3,4-tetrahydro-6-methoxyquinoxaline
Satam, Vijay,Rajule, Rajkumar,Bendre, Samir,Bineesh, Purushotthaman,Kanetkar, Vinod
, p. 221 - 225 (2009)
The novel 1,4-diethyl-1,2,3,4-tetrahydro-7-methoxyquinoxalin-6- carboxaldehyde was synthesized, characterized, and condensed with suitably substituted active methylene compounds by classical Knoe- venagel condensation reaction to obtain novel monostyryl dyes 8a-8e and a bis-styryl dye 8f. These novel styryl dyes have hue varying from orange to violet. The dyes were applied to polyester fibers. The spectral and thermal characteristics of the dyes and fastness properties of the dyed polyester fabric were investigated.
Diamination of phenylene dihalides catalyzed by a dicopper complex
Liao, Bei-Sih,Liu, Shiuh-Tzung
, p. 6653 - 6656 (2012)
Diamination of phenylene dihalides with aqueous ammonia to give the corresponding phenylenediamines can be achieved by using a dicopper complex [Cu2(bpnp)(OH)(CF3COO)3] (1) (bpnp = 2,7-bis(pyridine-2-yl)-l,8-naphthyridine) as the catalyst in the presence of Bu4NBr and Cs2CO3 in high yields. In addition, 1,3,5-tribromobenzene was converted into benzenetriamine quantitatively under the same conditions. This method offers a new opportunity, particularly simplifying steps and increasing yields, for the preparation of aryl diamines.
Synthesis and characterization of new rhodamine dyes with large Stokes shift
Tian, Zhidan,Tian, Baozhu,Zhang, Jinlong
, p. 1132 - 1136 (2013)
Two new rhodamine dyes (Rh Q-H, Rh Q-Me) containing 1, 4-diethyl-1, 2, 3, 4-tetrahydroquinoxaline as an effective electron donor are designed and synthesized. The structures of the novel compounds are confirmed by 1H NMR, 13C NMR and ESI. Due to an excited-state intramolecular charge transfer (ICT), the new dyes exhibit longer absorption (>580 nm) and emission (>640 nm) compared with the model compounds, rhodamine 101 and rhodamine 6G. The new rhodamine dyes show large Stokes shift of 40-50 nm in commonly used solvents. Notably, when measured in a mixture of H2O/EtOH solution, significant stokes shift of 65-68 nm are achieved, which is among the largest Stokes shifts ever reported for rhodamine dyes.
Expedient synthesis of electronically modified luciferins for bioluminescence imaging
McCutcheon, David C.,Paley, Miranda A.,Steinhardt, Rachel C.,Prescher, Jennifer A.
, p. 7604 - 7607 (2012)
Bioluminescence imaging with luciferase enzymes requires access to light-emitting, small-molecule luciferins. Here, we describe a rapid method to synthesize d-luciferin, the substrate for firefly luciferase (Fluc), along with a novel set of electronically modified analogues. Our procedure utilizes a relatively rare, but synthetically useful dithiazolium reagent to generate heteroaromatic scaffolds in a divergent fashion. Two of the luciferin analogues produced with this approach emit light with Fluc in vitro and in live cells. Collectively, our work increases the number of substrates that can be used for bioluminescence imaging and provides a general strategy for synthesizing new collections of luciferins.
