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1.
DEEB MARJI KHAMIS ABBAS 《Journal of inclusion phenomena and macrocyclic chemistry》1997,27(4):269-277
The effect of 18-crown-6 and kryptofix (2,2,1) on the oxidation of triethylamine byaqueous ferricyanide ion has been studied at pH 4, 7, and 9.The macrocycle retarded the normal oxidation process at all pH values,the effect depending on the macrocyclic ligand concentration Kryptofix (2,2,1) had a greater effect than 18-crown-6 at all pHvalues in this study. For 18-crown-6, retardation decreases in the order pH 9 > 4 > 7 while forkryptofix it follows the order pH 9 > 7 > 4. 相似文献
2.
The Wittig—Horner reaction of CbzNHCH(CO2Me)P(O)(OMe)2 (1) with ArCHO (2) in the presence of Et3N as a base affords methyl (Z)-3-aryl-2-(carbobenzoxyamino)acrylates (3) with high degrees of diastereoselectivity (Z)/(E) > 101. One recrystallization of the crude product is sufficient to obtain isomerically and chemically pure (Z)-3.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2218-2220, November, 1995.The authors are grateful to the Dupont company (USA) for financing this study 相似文献
3.
Christophe Biot Jean Dessolin Isabelle Ricard 《Journal of organometallic chemistry》2004,689(25):4678-4682
Starting from triazacyclononane, easily accessible ferrocenic quinoline derivatives were synthesized. Their antiplasmodial properties were investigated against chloroquine sensitive (HB3) and chloroquine-resistant (Dd2) Plasmodium falciparum. One of them, 7-chloro-4-[4-(7-chloro-4-quinolyl)-7-ferrocenylmethyl-1,4,7- triazacyclononan-1-yl]quinoline (4) showed potent antimalarial activity in vitro against the chloroquine-resistant strain Dd2 and therefore revealed to be the most promising lead from the present work for new organometallic antimalarial agents. 相似文献
4.
Pullin等人曾对全氟碘代烷与三级胺的相互作用进行了研究,发现R_(?)I与NR_3能形成电荷转移络合物,即:R_(?)…I…NR_3。但此后却未见到有关反应的报道。我们发现在钯催化剂存在下,全氟碘化物与三乙胺能发生反应,反应条件较为温和,产物为氟代烷基烯基二乙基胺1。反应可能是在三乙胺中先产生一个双键,然后β碳原子接上一个全氟烷基。1的IR和NMR与Blanc报道的一致。化合物1经水解可得胺基烯酮2。在酸溶液中水解时,速度明显加快,而在碱溶液中,不仅不能加快水解速度,而且还有副反应发生。我们对化合物2进 相似文献
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Ângela F. S. S. Mendonça Dina T. R. Formigo Isabel M. S. Lampreia 《Journal of solution chemistry》2002,31(8):653-670
Solubilities of triethylamine in aqueous tetraethylammonium chloride solutions were measured at 20, 25, and 35°C. The molalities in Et4NCl of the aqueous solvents ranged from 0.03 to 1 mol-kg–1. The data were evaluated from density measurements using a vibrating-tube densimeter. At each temperature, least-squares method was used to fit experimental density data points to double polynomial equations of various degrees. Triethylamine molalities of the saturated aqueous phases were estimated by extrapolation from those equations. Experimental data were interpreted in terms of hydrophobic and electrostatic perturbed domains in the hydration shells of the noneleceory and of the cation of the salt, as a function of temperature and salt concentration. The conclusions obtained are consistent with previous volumetric studies. 相似文献
9.
《Arabian Journal of Chemistry》2022,15(4):103712
Although recent decades have witnessed the synthesis of 1,3,4-thiadiazoles via phosphorus POCl3-promoted cyclization reaction, simultaneous access to 2-amino-1,3,4-thiadiazole and 2-amino-1,3,4-oxadiazole analogs remains unexpected and elusive. Herein, a detailed regiocontrolled synthesis of 2-amino-1,3,4-thiadiazoles in good to high yields with good regioselectivities from readily available thiosemicarbazides using POCl3 was disclosed. Meantime, to establish a comprehensive structure–activity relationship, 2-amino-1,3,4-oxadiazole derivatives as single regioisomers were prepared via EDCI·HCl-triggered cyclization of the thiosemicarbazide intermediates. The in vitro anti-influenza assays proved that the selected compounds with the pyrazine/pyridine ring exhibited certain inhibitory activities against influenza A virus strains A/HK/68 (H3N2) and A/PR/8/34 (H1N1) in MDCK cells. Among them, N-(adamantan-1-yl)-5-(5-(azepan-1-yl)pyrazin-2-yl)-1,3,4-thiadiazol-2-amine (4j) was the most active compound, and exhibited favorable activity with EC50 values of 3.5 μM and 7.5 μM, respectively. In addition, the molecular docking results explained the reason why compound 4j had dual inhibitory activity and revealed the reasonable binding mode of this compound with the M2-S31N and M2-WT ion channels. This compound had the potential to be further developed as an anti-influenza drug. 相似文献
10.
Jae‐Woon Nah Mi‐Kyeong Jang 《Journal of polymer science. Part A, Polymer chemistry》2002,40(21):3796-3803
Low molecular, water‐soluble chitosan (LMWSC) with a free amine group was prepared by the novel salts‐removal method described in this study. A weight‐average molecular weight and degree of deacetylation (DDA) of LMWSC were determined by viscometry and Kina titration, resulting in 18,579 Da and 93% DDA, respectively. In the Fourier transform infrared spectroscopic, 1H NMR, and 13C NMR spectra the absorption band by the carboxyl group derived from lactic acid and the impurities formed in the enzymatic process disappeared or were significantly lower than that of the control chitosan. Also, from the 1H NMR and 13C NMR spectra the empirical value for the area ratio of the proton and carbon corresponds nearly to its theoretical values. The matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrum identified the difference in the two adjacent peaks as 161. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3796–3803, 2002 相似文献