Androvič, L.; Drabina, P.; Panov, I.; Frumarová, Božena; Kalendová, A.; Sedlák, M.
Roč. 25, č. 9 (2014), s. 775-780. ISSN 0957-4166 Institutional support: RVO:61389013 Keywords : cooper complexes * copolymers * asymmetric Henry reaction Subject RIV: CC - Organic Chemistry Impact factor: 2.155, year: 2014
The following work describes the synthesis of compounds carrying a vicinal difluoro motif and the evaluation of this structural element to influence the conformation of organic molecules. The synthesis of erythro and threo 1,2-difluoro-1,2-diphenylethane was achieved by bromofluorination and subsequent halogen exchange from stilbene. Oxidative degradation of the phenyl rings allowed to access erythro and threo 2,3- difluorosuccinic acids and a variety of derivatives thereof. Th...
Pulse radiolysis of 1,2-di(α-naphthyl)ethane (1,2-DNE) was performed in deoxygenated pure methanol and tetrahydrofuran (THF). Absorption spectra and kinetics of 1,2-DNE- in both solvents are presented. In methanol 1,2-DNE- is formed and decays by a second order reaction. No cleavage of benzylic C-C bond occurs as has been observed in the presence of alkali metals in ethers. Hence, it can be concluded that the assistance of the metal cations is necessary for the reductive bond splitting process. For comparison, 1-bromomethylnaphthalene (Br-MN) and 1,2-diphenylethane (1,2-DPE) were investigated in deoxygenated methanol and results are given. Probable reaction mechanisms are presented. (author)
In this paper, we synthesize and report a Cu2+-sensing probe with two detection channels, 6,6′-(1E,1′E)-((2E,2′E)-(1,2-diphenylethane-1,2-diylidene) bis(hydrazine-2,1-diylidene))bis(methan-1-yl-1-ylidene)bis (3-(diethylamino)phenol) (referred to as BDBP). Its colorimetric and fluorescence quenching sensing responses towards Cu2+ ion are fully investigated. It is found that BDBP can recognize Cu2+ by forming a large conjugation plane with it, resulting in a red shift of electronic transition and correspondingly color-switching of BDBP. Correspondingly, the absorption and emission spectra of BDBP are both sensitive towards Cu2+ ion with high sensitivity, as well as excellent selectivity. Based on above sensing mechanism, an AND logic operation can be achieved using Cu+ ion and ClO- as the inputs, making BDBP a promising candidate for further applications in molecular logic devices. -- Highlights: • A Cu2+-sensing probe with two sensing channels has been constructed. • Its sensing responses have been fully characterized and studied. • High sensitivity and good selectivity have been achieved by both sensing channels. • An AND logic operation can be achieved using Cu+ ion and ClO− as inputs
The thermolysis of 2,2,5,5-tetramethyl-3,4-diphenylhexane was carried out at temperatures above 300 degrees C in the absence and presence of D2(14 MPa). The presence of D2 results in a greatly increased yield of the major product, neopentylbenzene. However, at higher concentrations of starting material, up to 50% of the neopentylbenzene formed avoids deuterium incorporation, an outcome believed to result partly from participation of the phenylneopentyl radical in radical disproportionation reactions. The meso-isomer of starting material produces a substantial yield of stilbene in both the absence and presence of D2. Under D2, 1,2-diphenylethane is produced, and it is believed that stilbene and other alkenes present serve as D atom traps producing radicals which then participate in termination by disproportionation. Remarkably, the d,l-diastereomer gives a different product distribution than the meso-isomer, giving very little stilbene or other products of tertbutyl group loss. However, both systems produce 1-phenyl-2-methyl-2-propene by methyl radical loss form the phenylneopentyl radical. The formation of such alkenes and the path to termination they provide is blamed for the absence of efficient kinetic chains involving D atoms. 1 fig., 6 tabs
Aqueous toluene solutions have been irradiated with Co γ-rays. In unbuffered solutions the various cresol isomers are formed in a total yield of 0.45, 0.87 and 0.94 molecules/100 eV absorbed energy in argon-, N2O- and air - saturated solutions, respectively. The yields are reduced in acid (pH 3) solutions (G 0.14, 0.14 and 0.52, respectively) but the reduction is compensated by the formation of 1,2-di-phenylethane in yields of 0.49 and 1.60 in argon- and N2O-saturated solutions, respectively. Benzyl radicals are formed through an acid catalysed water elimination reaction from the initially formed hydroxymethylcyclohexadienyl radical. Phenyltolylmethanes, dimethylbiphenyls and partly reduced dimers are also formed during the radiolysis. Hydrogen is formed in the same yield as the molecular yield, g(H2). Xylene isomers and benzene are formed in trace quantities. The most remarkable effects of the addition of Fe(III) ions to deaerated acid toluene solutions are the formation of benzyl alcohol and benzaldehyde and an increase in the yield of 1,2-diphenylethane
The spontaneous release, or shedding, of cell surface components into the extracellular medium may be important in the determination of several features of the cancer cell phenotype. The release of macromolecules from the Erhlich mouse ascites tumor cell was studied under a variety of experimental conditions to elucidate the origin and the underlying mechanisms of release. The extrinsic macromolecules are a diverse group with apparent molecular weights ranging from 13,500 to 400,000 daltons. External labeling of the cell surface with tritiated 4,4'-diisothiocyano-1,2-diphenylethane-2,2-disulfonic acid ([3H]H2DIDS) reveals a slow loss of labeled components at 4 degrees C, while at 21 degrees C and 37 degrees C an initial rapid loss is followed by a slower release. In vitro metabolic labeling with [1-14C]-D-glucosamine hydrochloride, D-[2-3H]-mannose and various [3H]-L-amino acids results in the appearance of labeled macromolecules in the medium suggesting tumor, not mouse, origin. These data suggest that the extrinsic macromolecules originate from the cell surface. Macromolecules are shed by a temperature and pH sensitive process. These results suggest that a limited proteolytic digestion, or sublethal autolysis, of the cell surface may occur in this system. The macromolecules shed by the Ehrlich cell originate from the surface and are probably released by sublethal autolysis, direct secretion and a passive process
Shimakoshi, Hisashi; Luo, Zhongli; Inaba, Takuya; Hisaeda, Yoshio
The electrolysis of benzotrichloride at -0.9 V vs. Ag/AgCl in the presence of the B12 model complex, heptamethyl cobyrinate perchlorate, in ethanol under aerobic conditions using an undivided cell equipped with a platinum mesh cathode and a zinc plate anode produced ethylbenzoate in 56% yield with 92% selectivity. The corresponding esters were obtained when the electrolysis was carried out in various alcohols such as methanol, n-propanol, and i-propanol. Benzoyl chloride was detected by GC-MS during the electrolysis as an intermediate for the ester formation. When the electrolysis was carried out under anaerobic conditions, partially dechlorinated products, 1,1,2,2-tetrachloro-1,2-diphenylethane and 1,2-dichlorostilibenes (E and Z forms), were obtained instead of an ester. ESR spin-trapping experiments using 5,5,-dimethylpyrroline N-oxide (DMPO) revealed that the corresponding oxygen-centered radical and carbon-centered radical were steadily generated during the electrolyses under aerobic and anaerobic conditions, respectively. Applications of the aerobic electrolysis to various organic halides, such as substituted benzotrichlorides, are described. Furthermore, the formation of amides with moderate yields by the aerobic electrolysis of benzotrichloride catalyzed by the B12 model complex in the presence of amines in acetonitrile is reported. PMID:27071703
Glucose-6-P (G6P) hydrolysis by hepatic microsomes (MS) is mediated by a coupled system composed of the G6P transporter (T1), the enzyme (E) and a phosphate transporter (T2). Zoccoli et al. concluded that T1 is a 54 kDa protein based on a linear correlation of labeling by 3H-4,4'diisothiocyano-1,2-diphenylethane-2,2'-disulfonate (3H-H2DIDS) and inhibition of system activity. The authors cannot support this conclusion: (1) in their hands the reaction of 3H-H2DIDS with MS proteins is extremely nonspecific, and (2) the linear correlation must be between labeling and inhibition of T1 activity, because transport per se is not the absolute rate limiting step in hydrolysis by the system. Point 2 is readily demonstrated by examining the influence of the enzyme inhibitor, D-glucose, on the sensitivity of the system to inhibition by H2DIDS. Studies of H2DIDS inhibition of the system in MS from fasted and diabetic rats revealed that the observed inhibition constant for the system, K/sub i(S)/, is inversely proportional to the fraction of latent G6Pase activity (LF) seen before exposure to H2DIDS, and K/sub i(S)/ x LF - K/sub i(T1)/, the inhibition constant for T1 activity. This relationship is derived from the equation 1/V/sub (S)/ - 1/V/sub (E)/ = 1/V/sub (T1)/, where V denotes the initial rates of S, E and T1, respectively. The latter equation can be used to calculate V/sub (T1)/ for any preparation of intact MS, and it predicts that labeling and inhibition of T1 will be linearly correlated with V/sub (T1)/ but not V/sub (S)/
赵少静; 程发; 陈宇; 魏玉萍; 于占龙
A series of sulfonic-acid type Gemini surfactants were synthesized from 1, 2-diphenylethane and long-chain aliphatic acyl chloride. Products obtained were characterized by 'H NMR and FT-IR; surface tension curve and related parameters were acquired by surface tension measurements. Results showed that the critical micelle concentration (CMC) decreased with the increasing hydrophobic chain length. Compared with the corresponding linear sodium dodecyl benzene sulfonate (SDBS) ,the C20 and CMC of Gemini surfactant G12-2-12 decreased by 94.4% and 91.3%,respectively. The area occupied by the surfactant molecule at the air/water interfaceC4min)of G12-2-12 was 27%, less than two times that of SDBS, which suggested that Gemini surfactants packed more closely.%以二苯乙烷和长碳链脂肪酰氯为原料合成出Gemini磺酸表面活性剂,通过核磁氢谱和红外光谱对化合物的结构进行表征,测定了其水溶液的表面张力,得出其表面张力曲线,进而算出其他相关参数3种Gemini表面活性剂的临界胶束浓度(CMC)值随烷基疏水碳链的增长而降低.与线性十二烷基苯磺酸钠(SDBS)相比,Gemini表面活性剂G12-2-12的C20值降低94.4％,CMC值降低91.3％.G12-2-12的饱和吸附面积(Amin)比对应单基表面活性剂的2倍降低27％,且Gemini表面活性剂在气液界面上排列更加紧密.