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1.
Novel pyrrolo[1′,5′‐a]‐1,8‐naphthyridine compounds have been synthesized through a facile one‐pot process by the reaction of the corresponding 1,8‐naphthyridines with aliphatic anhydride. The structures were established by spectroscopic data. Further X‐ray crystal analysis of 4′‐acetyl‐7‐methyl‐pyrrolo[1′,5′‐a]‐1,8‐naphthyridine (1) identifies its intriguing molecular structure and reveals the strong π‐π stacking. 相似文献
2.
The methods for the synthesis of oxazolo[3,2-a]pyridinium and oxazolo[3,2-a]pyrimidinium salts and their reactivities are reviewed. Both systems exhibit ambident properties in reactions with nucleophiles;
depending on the substituents and the reagents, both the oxazole and azine rings can undergo opening and transformations.
A number of new methodologies involving oxazolopyridinium and oxazolopyrimidinium salts for the design of functionalized oxazoles,
imidazoles, fused pyrroles, and other heterocyclic systems are generalized.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 831–848, April, 2008. 相似文献
3.
Reaction of 2‐phenylindolizine‐3‐carbothialdehyde with amine derivatives provides a new, mild and efficient synthesis of a series of heterocyclic imines. The corresponding structures of products were established by IR, 1H NMR, MS and elemental analysis. And the reaction mechanisms was also discussed. 相似文献
4.
Ethyl 2-hydroxy-1-(2-thioxopyridin-1(2H)-yl)indolizin-3-carboxylate was formed along with ethyl (2-thioxopyridin-1(2H)-acetate
from the reaction of 2-bromo-1-(ethoxycarbonylmethyl)pyridinium bromide with sodium sulfide. The structures of all compounds
were confirmed by X-ray crystallography.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, 1250–1255, August, 2005. 相似文献
5.
6.
Dr. Aron J. Huckaba Dr. Aswani Yella Dr. Louis E. McNamara April E. Steen J. Scott Murphy Casey A. Carpenter George D. Puneky Prof. Nathan I. Hammer Prof. Mohammad Khaja Nazeeruddin Prof. Michael Grätzel Prof. Jared H. Delcamp 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15536-15542
Desirable components for dye‐sensitzed solar cell (DSC) sensitizers and fluorescent imaging dyes include strong donating building blocks coupled with well‐balanced acceptor functionalities for absorption beyond the visible range. We have evaluated the effects of increasing acceptor strengths and incorporation of dye morphology controlling groups on molar absorptivity and absorption breadth with indolizine donor‐based dyes. Indolizine‐based D –A and D –π–A sensitizers incorporating bis‐rhodanine, tricyanofuran (TCF), and cyanoacrylic acid functionalities were analyzed for performance in DSC devices. The TCF derivatives were also evaluated as near‐infrared (NIR)‐emissive materials with the AH25 emissions extending past 1000 nm. 相似文献
7.
E. V. Babaev A. A. Tsisevich D. V. Al’bov V. B. Rybakov L. A. Aslanov 《Russian Chemical Bulletin》2005,54(1):259-261
An unusual example of the recyclization of the tricyclic 6,7,8,9-tetrahydrooxazolo[3,2-a]quinolinium system into the 8,9-dihydro-7H-pyrrolo[3,2,1-ij]quinoline system was discovered. The reaction is a topological modification of the known conversion of oxazolo[3,2-a]pyridinium salts into indolizines. The structural feature of this transformation is a change of the annelation type in the tricycle from the angular one to peri-fusion of three rings.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 253–255, January, 2005. 相似文献
8.
A new fluorescent indolizine-based scaffold was developed using a straightforward synthetic scheme starting from a pyrrole ring. In this fluorescent system, an N,N-dimethylamino group in the aryl ring at the C-3 position of indolizine acted as an electron donor and played a crucial role in inducing a red shift in the emission wavelength based on the ICT process. Moreover, various electron-withdrawing groups, such as acetyl and aldehyde, were introduced at the C-7 position of indolizine, to tune and promote the red shift of the emission wavelength, resulting in a color range from blue to orange (462–580 nm). Furthermore, the ICT effect in indolizine fluorophores allowed the design and development of new fluorescent pH sensors of great potential in the field of fluorescence bioimaging and sensors. 相似文献
9.
Sophie Fourmentin Georgiana G. Surpateanu Philippe Blach David Landy Patrick Decock Gheorghe Surpateanu 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(3-4):263-269
Inclusion equilibria of a new fluorescent indolizine modified β-cyclodextrin were studied in aqueous solution to evaluate its use as a fluorescent chemo-sensor for volatile organic compounds (VOCs). The host compound shows a decrease of the fluorescence intensity by adding adamantanol, benzene, toluene, phenol and p-cresol as guest. The sensing parameter (ΔI/I
0) was used to show the sensing ability of the host. The formation constant values measured using a spectral displacement method and a specific algorithm treatment are reported. Although the guest binding ability of the sensor is not enhanced by the existence of the hydrophobic cap, this new cyclodextrin sensor shows a very strong sensing ability. The experimental values of the constants were in good agreement with the computed complexation energies, ΔE, from molecular mechanics modelling of the inclusion process. 相似文献
10.
Mohammed A. S. Abourehab Alaa M. Alqahtani Faisal A. Almalki Dana M. Zaher Ashraf N. Abdalla Ahmed M. Gouda Eman A. M. Beshr 《Molecules (Basel, Switzerland)》2021,26(21)
In the current study, eight new hybrids of the NSAIDs, ibuprofen and ketoprofen with five pyrrolizine/indolizine derivatives were designed and synthesized. The chemical structures of these hybrids were confirmed by spectral and elemental analyses. The antiproliferative activities of these hybrids (5 μM) was investigated against MCF-7, A549, and HT-29 cancer cell lines using the cell viability assay, MTT assay. The results revealed 4–71% inhibition of the growth of the three cancer cell lines, where 8a,e,f were the most active. In addition, an investigation of the antiproliferative activity of 8a,e,f against MCF-7 cells revealed IC50 values of 7.61, 1.07, and 3.16 μM, respectively. Cell cycle analysis of MCF-7 cells treated with the three hybrids at 5 μM revealed a pro-apoptotic increase in cells at preG1 and cell cycle arrest at the G1 and S phases. In addition, the three hybrids induced early apoptotic events in MCF-7 cells. The results of the molecular docking of the three hybrids into COX-1/2 revealed higher binding free energies than their parent compounds 5a,c and the co-crystallized ligands, ibuprofen and SC-558. The results also indicated higher binding free energies toward COX-2 over COX-1. Moreover, analysis of the binding modes of 8a,e,f into COX-2 revealed partial superposition with the co-crystallized ligand, SC-558 with the formation of essential hydrogen bonds, electrostatic, or hydrophobic interactions with the key amino acid His90 and Arg513. The new hybrids also showed drug-likeness scores in the range of 1.06–2.03 compared to ibuprofen (0.65) and ketoprofen (0.57). These results above indicated that compounds 8a,e,f deserve additional investigation as potential anticancer candidates. 相似文献