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11.
Besma Mellah Rym Abidi Haiko Herchbach Kwanghyun No Jong Seung Kim Françoise Arnaud Hubscher Veronique 《Journal of inclusion phenomena and macrocyclic chemistry》2010,66(1-2):153-161
The binding properties of four amido derivatives of p-tetraphenyl tetrahomodioxacalix[4]arene towards alkali and alkaline-earth metal cations using UV-absorption spectrophotometry, 1H NMR and ESI-mass spectrometry techniques are reported. 相似文献
12.
Issam Oueslati Rym Abidi Pierre Thuéry Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2003,47(3-4):173-178
A systematic study of extraction properties and complexation behaviour of the calix[4](aza)crown 1 towards alkaline earth (Mg2+, Ca2+,Sr2+, Ba2+) and transition metal (Co2+, Ni2+, Cu2+,Zn2+) cations is presented. The binding behaviour of 1 was also investigated by 1H-NMR and the crystal structure of the 1:1 complex with Mg2+ isdescribed. 相似文献
13.
Hyperbranched calix[4] (4) and calix[4]-dendrimer (5) as a second generation (G2) of calixdendrimers have been synthesized by divergent and convergent synthesis via amidation reactions. 相似文献
14.
Synthesis of 2- or 3-substituted Alkanediphosphonic Acids Syntheses of substances of the general formula RCX(PO3H2)2 X = OH, H, Cl, NH2 have been known for a long time. The preparative possibilities for the synthesis of alkanediphosphonic acids containing an amino group or a chlorine atom in the 2- or 3-position were limited, only 2 substances from this class of compounds being known. Further examples of this class of substances have been synthesized. 相似文献
15.
Issam Oueslati Rym Abidi Zouhair Asfari Jacques Vicens Bernardo Masci Pierre Thuéry Martine Nierlich 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):353-355
The synthesis and X-ray crystalstructure of a novel tetrahomodioxacalix[6]arenehexamethylester 2 arepresented. Preliminary investigations of alkali metal ioncomplexation showed that 2 is apoor extractant with selectivity for lithium. 相似文献
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17.
Rym Skanji Mhamed Ben Messaouda Yongmin Zhang Manef Abderrabba Henri Szwarc Fathi Moussa 《Tetrahedron》2012,68(12):2713-2718
While direct photo-addition of glycine-methyl-esters (GME) to [60]fullerene (C60) can yield a complex product mixture, only a fulleropyrrolidine (FP) mono-adduct has been characterized and the mechanism remains to be ascertained. We show here that visible light irradiation of a mixture of C60 and GME in the presence of oxygen is a direct route to synthesize sequentially higher FP poly-adducts through an unprecedented cyclization–deamination mechanism. Each step of this mechanism leads to a FP adduct involving the correlated addition of two GME radicals and the departure of an ammonia molecule. 相似文献
18.
Bouchendira R Cladé P Guellati-Khélifa S Nez F Biraben F 《Physical review letters》2011,106(8):080801
We report a new measurement of the ratio h/m(Rb) between the Planck constant and the mass of (87)Rb atom. A new value of the fine structure constant is deduced, α(-1)=137.035999037(91) with a relative uncertainty of 6.6×10(-10). Using this determination, we obtain a theoretical value of the electron anomaly a(e)=0.00115965218113(84), which is in agreement with the experimental measurement of Gabrielse [a(e)=0.00115965218073(28)]. The comparison of these values provides the most stringent test of the QED. Moreover, the precision is large enough to verify for the first time the muonic and hadronic contributions to this anomaly. 相似文献
19.
Hajer Ammar Imen Touihri Ahmed Eid Kholif Yassine MRabet Rym Jaouadi Mireille Chahine Mario E. de Haro Marti Einar Vargas-Bello-Prez Karim Hosni 《Molecules (Basel, Switzerland)》2022,27(20)
The main objective of this research was to study the biological characteristics in terms of antioxidant and antimicrobial activities of Ajuga iva and determine the best analytical and extraction methods applicable to this specie and studied compounds. A short screening of its nutritional value in terms of chemical composition is also included. A. iva leaves were analyzed for crude protein (CP), cell wall [neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL)], minerals, fatty acids, essential oils, and phenolic compounds. Mature aerial parts of A. iva were randomly collected during the Spring season from Mograne-Zaghouan, Tunisia. Leaves of A. iva contained 13.4 ± 0.4% CP, 26.3 ± 0.35% NDF, 20.2 ± 0.42% ADF, and 5.13 ± 0.21% ADL. Mineral content (13.0 ± 0.45%) was mainly composed of potassium (4.5% g DM) and magnesium (4.25% DM). Leaves of A. iva had linolenic (26.29 ± 0.760%) and linoleic (37.66 ± 2.35%) acids as the main components of the acid profile. Thymol was found to be the most dominant (23.43%) essential oil, followed by 4-vinylguaiacol (14.27%) and linalool (13.66%). HPLC-PDA-ESI-MS/MS analysis pointed out the presence of phytoecdysteroids. Phenolic acids and flavonoids, such as glycosylated derivatives of naringenin, eriodyctiol, and apigenin, were detected in the methanol extract of A. iva leaves. Our results underline the importance of choosing proper extraction methods and solvents to extract and characterize the described compounds profile of A. iva leaves. Results also show A. iva leaves as a potential source of functional ingredients with beneficial health-promoting properties. Overall, leaves of A. iva have low biological activities (antioxidant and antimicrobial activities) with a chemical composition suitable as a feed for ruminants in rangeland pasture. It also has low-grade antibacterial or medicinal characteristics when fed to ruminants. 相似文献
20.
Rym ElFessi Oussema Khamessi Najet Srairi-Abid Jean-Marc Sabatier Jan Tytgat Steve Peigneur Riadh Kharrat 《Molecules (Basel, Switzerland)》2022,27(21)
Scorpion venom is a rich source of promising therapeutic compounds, such as highly selective ion channel ligands with potent pharmacological effects. Bot33 is a new short polypeptide of 38 amino acid residues with six cysteines purified from the venom of the Buthus occitanus tunetanus scorpion. Bot33 has revealed less than 40% identity with other known alpha-KTx families. This peptide displayed a neutral amino acid (Leucine), in the position equivalent to lysine 27, described as essential for the interaction with Kv channels. Bot33 did not show any toxicity following i.c.v. injection until 2 µg/kg mouse body weight. Due to its very low venom concentration (0.24%), Bot33 was chemically synthesized. Unexpectedly, this peptide has been subjected to a screening on ion channels expressed in Xenopus laevis oocytes, and it was found that Bot33 has no effect on seven Kv channel subtypes. Interestingly, an in silico molecular docking study shows that the Leu27 prevents the interaction of Bot33 with the Kv1.3 channel. All our results indicate that Bot33 may have a different mode of action from other scorpion toxins, which will be interesting to elucidate. 相似文献