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91.
Fumihiro Ito Shin AndoMasato Iuchi Taki UkariMomoka Takasaki Kentaro Yamaguchi 《Tetrahedron》2011,67(41):8009-8013
An effective 15N- and deuterium (D)-labeled 2,6-bis(oxazolin-2-yl)pyridine (pybox)-La complex based probe ionization method that produces a distinct isotopic shift was developed. The distinct isotopic shift was detected by using the newly synthesized 15N-D-labeled pybox complexes. Moreover, O-[3-(tetramethylpybox)-propyl]-hydroxylamine (oxime-TMpybox) was prepared for attachment to the carbonyl group of the target molecule. Distinct isotopic shifts and multiple charged ions were detected for various compounds having amino, thiol, carboxyl, and carbonyl groups and fullerenes, using the TMpybox ionic probe series in cold-spray ionization mass spectrometry. 相似文献
92.
A series of organotin(IV) compounds R3Sn(A) where R = Me or Ph and A is a chromogenic nitrophenolate ligand were prepared and studied as possible colorimetric sensors for anions (F−, Cl−, Br−, AcO−, H2PO4−). Equilibrium constants for a complete set of reactions between R3Sn(A) with A = 2‐amino‐4‐nitrophenolate (ANP) or 4‐nitrophenolate and anions (X−) involving formation of complexes R3Sn(A)(X)− and substitution products R3Sn(X) and R3Sn(X)2− were determined by UV‐vis and 1H NMR titrations in MeCN and DMSO. The binding selectivity was AcO− > F− > H2PO4− > Cl− ≫ Br− in both solvents and both for R = Me and Ph with higher affinity for R = Ph. Compounds with A = ANP were found to have the optimum properties as anion sensors allowing optical detection of F−, AcO− and H2PO4− anions in the 5–100 µM range by appearance of an intense absorption band of free ANP resulting from its substitution with the analyte. Selectivity and affinity of anion interactions with R3Sn(ANP) are similar to those for thiourea receptors, but the organotin receptor produces a much larger naked eye detected optical signal, operates equally well in nonpolar and polar solvents and tolerates the presence of up to 20% vol. of water in DMSO. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
93.
94.
Condensation of aldehydes, isonitriles and 2‐aminopyridines in the presence of H3PMo12O40 affords different derivatives of 3‐aminoimidazo[1,2‐a]pyridine in good to excellent yields. 相似文献
95.
Luca Beverina Dr. 《Chemphyschem》2010,11(10):2075-2077
96.
97.
98.
The effect of tributyltin‐chloride (TBTC), dibutyltin‐chloride (DBTC) and monobutyltin‐chloride (MBTC) on rainbow trout (Salmo irideus) nuclear DNA, was investigated by means of single cell gel electrophoresis (‘comet’ assay). Our data show that TBTC presents a marked genotoxic effect, whereas the genotoxic effect is less pronounced for DBTC and it is completely absent for MBTC. These results could be important in evaluating the environmental risks deriving from the use of these molecules as a antifouling agents in marine paints and as agricultural biocides. Copyright © 2001 John Wiley & Sons, Ltd.
Abbreviations:
-
- TBTC,
-
- tributyltin‐chloride;
-
- DBTC,
-
- dibutyltin‐chloride;
-
- MBTC,
-
- monobutyltin‐chloride;
-
- Hb,
-
- hemoglobin.
99.
Thermal behaviour of tri(O,O'-diisopropyldithiophosphate)cobalt(III), Co(dptp)3 and bis (O,O'-diethyldithiophosphate)nickel(II), Ni(detp)2 and its adducts with pyridine, Ni(detp)2(py)2 or 4-methylpyridine, Ni(detp)(mpy)2 in a dynamic nitrogen atmosphere was investigated by TG-DTG and DSC techniques, which showed a medium endothermic peak for
the evolution process of pyridine(or 4-methylpyridine) and a strong exothermic peak for that of O,O'-diethyldithiophosphate.
The thermal stability and decomposition patterns for these compounds were compared and interpreted in terms of structural
features such as bond character and steric effects. The kinetic parameters and mechanisms of every decomposition stage involved
for all these complexes were obtained employing the non-isothermal kinetic analysis method suggested by Malek et al., which
showed the kinetics mechanism for pyrolysis of pyridine(or 4-methylpyridine) is an S-B empirical model with lower activation
energy, while that of O,O'-dialkyldithiophosphate is a diffusion model. These results are in accord with the fact that two
ligands are of different type.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
100.
Irina Iovel Lena Golomba Sergey Belyakov Andrejs Kemme Edmunds Lukevics 《应用有机金属化学》2001,15(9):733-743
A series of novel Shiff bases (1a–h) was synthesized by condensation of pyridinecarboxaldehydes (1–4) with 3‐ and 4‐trifluoromethylanilines (5, 6) in the presence of molecular sieves (4 Å). It was found that AlCl3 and AlBr3 catalyzed the addition of Me3SiCN to the C?N bond of the imines obtained, whereas the other Lewis acids studied (YCl3, LaCl3, ZnI2) were not active. The reactivity of the imines in the title reaction, on the whole, correlated with their basicity. Besides the addition giving the expected α‐amino nitriles (2a,b,d–f,h), an unusual reaction leading to unsaturated nitriles (3a–h) was observed. The structures of saturated and unsaturated products 2d and 3c were determined by X‐ray diffraction. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献