- Malonic Acid Derivatives on Duty as Electron-Withdrawing Units in Push–Pull Molecules
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Based on the 2-(N-piperidinyl)thiophene central donor, 32 model push–pull molecules with systematically varied malonic acid-derived peripheral acceptors have been prepared. Further property tuning has been achieved by modifying the π-linker and the structural arrangement (linear vs. quadrupolar D–π–A systems). Malonic acid derivatives such as cyanoacetic acid, malondinitrile, diethyl malonate, Meldrum′s acid, and N,N′-dibutyl(thio)barbituric acid as well as 1,3-diketo analogues dimedone and indan-1,3-dione were employed as acceptor moieties. Knoevenagel condensation with four thiophene aldehydes afforded the target chromophores in satisfactory yields. The electron-withdrawing abilities of malonic acid acceptors were examined both by experiment including X-ray analysis, differential scanning calorimetry, electrochemistry, and UV/Vis absorption spectroscopy, and by DFT calculations. Details of the structure–property relationships have been elucidated. According to the increasing electron-withdrawing ability, the widely used malonic acid acceptor units can be ordered: diethyl malonate ≤ cyanoacetic acid malondinitrile Meldrum's acid dimedone ≤ N,N′-dibutylbarbituric acid indan-1,3-dione ≤ N,N′-dibutylthiobarbituric acid.
- Klikar, Milan,Jelínková, Veronika,R??i?ková, Zdeňka,Mikysek, Tomá?,Pytela, Old?ich,Ludwig, Miroslav,Bure?, Filip
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p. 2764 - 2779
(2017/05/29)
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- ANTI-VIRAL USES FOR ANALOGS OF BARBITURIC ACID
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A method of using certain barbituric acid analogs to kill RNA viruses, including Group IV and Group V viruses such as SARS and influenza viruses. The barbituric acid analog may have the structure (S1) shown below: where R1 and R2 are independently hydrogen, C1-C6 alkyl, C1-C6 alkoxy, C1-C6 haloalkyl, C1-C6 hydroxyalkyl, C1-C6 aminoalkyl, C1-C6 mercaptoalkyl, or aryl; R3 is O, S, Se or C(CH3)2; and R4 is hydrogen. One particularly preferred barbituric acid analog has the structure (S1) shown above where R1 and R2 are both butyl, R3 is S, and R4 is hydrogen. The barbituric acid analogs may be used in vivo, such as in birds or in humans or other animals, or they may be used ex vivo, such as in air handling systems or on hard surfaces. The barbituric acid analogs may be incorporated into animal or bird feed or supplements. Particularly effective compositions of barbituric acid analogs dissolved in DMSO are also disclosed.
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Page/Page column 5
(2008/06/13)
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