173531-47-0Relevant academic research and scientific papers
Synthesis and Photoswitching Properties of Bioinspired Dissymmetric I-Pyrone, an Analogue of Cyclocurcumin
Pecourneau, Jérémy,Losantos, Raúl,Monari, Antonio,Parant, Stéphane,Pasc, Andreea,Mourer, Maxime
, p. 8112 - 8126 (2021/06/30)
Cyclocurcumin (CC), a turmeric curcuminoid with potential therapeutic properties, is also a natural photoswitch that may undergo E/Z photoisomerization under UV light. To be further exploited in relevant biological applications, photoactivation under near-infrared (NIR) irradiation is required. Such requirement can be met through opportune chemical modifications, by favoring two-photon absorption (TPA) probability. Herein, a general and efficient synthesis of a biomimetic 2,6-disubstituted-δ-pyrone analogue of CC is described, motivated by the fact that molecular modeling previews an order of magnitude increase of its NIR TPA compared to CC. Three retrosynthetic pathways have been identified (i) via an aryl-oxazole intermediate or via aryl-diynone through (ii) a bottom-up or (iii) a top-down approach. While avoiding the passage through unstable synthons or low-yield intermediate reactions, only the latest approach could conveniently afford the 2,6-disubstituted-I-pyrone analogue of CC, in ten steps and with an overall yield of 18%. The photophysical properties of our biomimetic analogue have also been characterized showing an improved photoisomerization yield over the parent natural compound. The potentially improved nonlinear optical properties, as well as enhanced stability, may be correlated to the enforcement of the planarity of the pyrone moiety leading to a quadrupolar D-π-A-π-D system.
Discovery and Characterization of Pure RhlR Antagonists against Pseudomonas aeruginosa Infections
Nam, SangJin,Ham, So-Young,Kwon, Hongmok,Kim, Han-Shin,Moon, Suhyun,Lee, Jeong-Hoon,Lim, Taehyeong,Son, Sang-Hyun,Park, Hee-Deung,Byun, Youngjoo
, p. 8388 - 8407 (2020/09/21)
Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic human pathogen that forms biofilms and produces virulence factors via quorum sensing (QS). Blocking the QS system in P. aeruginosa is an excellent strategy to reduce biofilm formation and the production of virulence factors. RhlR plays an essential role in the QS system of P. aeruginosa. We synthesized 55 analogues based on the chemical structure of 4-gingerol and evaluated their RhlR inhibitory activities using the cell-based reporter strain assay. Comprehensive structure-activity relationship studies identified the alkynyl ketone 30 as the most potent RhlR antagonist. This compound displayed selective RhlR antagonism over LasR and PqsR, strong inhibition of biofilm formation, and reduced production of virulence factors in P. aeruginosa. Furthermore, the survival rate of Tenebrio molitor larvae treated with 30 in vivo greatly improved. Therefore, compound 30, a pure RhlR antagonist, can be utilized for developing QS-modulating molecules in the control of P. aeruginosa infections.
Synthetic method for piceatannol derivatives and pharmaceutical compounds containing the piceatannol derivatives
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Paragraph 0023; 0055; 0056; 0058; 0059; 0061; 0062, (2017/10/31)
The piceatannol derivatives were easily synthesized using a Wittig-Horner reaction, a Colvin rearrangement and a Sonogashira reaction. According to the result of investigating the anti-inflammatory activity of compounds synthesized in RAW264.7 macrophages induced by LPS, compounds 6 to 8 showed remarkable activity at the concentration of 10 andmu;M, and a compound 7 (90.1%), a compound 8 (60.8%) and a compound 6 (55.2%) showed no cytotoxicity. The present invention aims to provide a method for efficiently synthesizing the piceatannol derivatives and to confirm the biological activity of synthesized piceatannol derivatives.COPYRIGHT KIPO 2017
Conjugation of Hydroxytyrosol with Other Natural Phenolic Fragments: From Waste to Antioxidants and Antitumour Compounds
Tassano, Erika,Alama, Angela,Basso, Andrea,Dondo, Giancarlo,Galatini, Andrea,Riva, Renata,Banfi, Luca
, p. 6710 - 6726 (2015/10/29)
Hydroxytyrosol, a natural polyphenol that can be extracted from olive mill waste waters, was converted into a series of more complex and lipophilic analogues by conjugation with other naturally derived (poly)phenolic fragments. Ether and triazole linkers were employed. A small library of compounds was prepared, stressing step economy and operational simplicity. Some of these substances were proven to have activity equal or superior to that of the parent hydroxytyrosol in radical scavenging assays as well as in cytotoxicity tests against tumour cells.
Synthesis of (S)-imperanene by using allylic substitution
Takashima, Yuji,Kobayashi, Yuichi
scheme or table, p. 5920 - 5926 (2009/12/26)
(Chemical Equation Presented) Synthesis of (S)-imperanene (1) was studied by using copper-assisted allylic substitution of ArCH=CHCH(L)CH2Ar (L: leaving group) and (i-PrO)Me2SiCH2MgCl. Preliminary substitution between PhCH=CHCH(L)Me (L = AcO, PivO, MeOCO2, (2-Py)CO2) and Bu copper reagents derived from BuMgX (X = Br, Cl) and CuBr·Me2S or CuCl in 1:1-40:1 ratios suggested acetate 28 as the best substrate. To prepare 28, kinetic resolution of racemic (E)-TMSCH=CHCH(OH)CH2Ar2 (Ar2 = (p-TBSO)(m-MeO)C6H3) carried out by using the asymmetric epoxidation with (-)-DIPT afforded the corresponding epoxy alcohol and (S)-allylic alcohol. After separation by chromatography, these products were converted to (S,E)-Bu3SnCH=CHCH(OH)CH2Ar2, which upon palladium-catalyzed coupling with Ar2-I followed by acetylation gave 28 (95-98% ee). Substitution of 28 with (i-PrO)Me 2SiCH2MgCl and CuBr·Me2S in a 4:1 ratio at 0°C proceeded cleanly to produce 29 with 100% inversion in 92% yield. Finally, Tamao oxidation furnished 1.
