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1.
本文主要评述了双官能团化合物——乙醇胺及其类似物的选择磷(膦)酰化反应和反应机理,并详细讨论了磷(膦,次膦)酰化产物的合成、物理化学性质和波谱特征。  相似文献   

2.
毒死蜱对雄性大鼠生精功能的影响   总被引:6,自引:0,他引:6  
探讨毒死蜱(chlorpyifos,CPF)对雄性大鼠生殖功能的影响.选择6周龄雄性SD大鼠按体重随机分成4组,每组10只.灌胃给予CPF,剂量为0(对照组)、0.82、2.45、7.35 mg/(kg·d).于染毒8周后,观察大鼠体重、睾丸和附睾重量及脏器系数、精子畸形率、精子计数、活动精子百分率,光镜病理学检查;检测睾丸组织匀浆的乳酸脱氢酶(LDH)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、γ-谷氨酰转移酶(γ-GT)的活性.与对照组比较,随CPF染毒剂量的增加,体重显著下降(P<O.05),染毒组睾丸重量显著升高(P<0.05),7.35 mg/kg染毒组附睾重量显著升高(P<0.05),各自脏器系数均显著升高(P<0.05).与对照组比较,7.35 mg/kg染毒组的附睾精子数及附睾精子活力显著降低,LDH和AKP的活性受到明显抑制(P<0.05).2.45、7.35 mg/kg染毒组的ACP活力较对照组显著降低,精子畸形率显著升高(P<0.05).3个染毒组γ-GT活性较对照组增加,差异显著(P<0.05).CPF可对机体产生明显的毒性作用,主要靶器官为睾丸,对大鼠精子形成和成熟过程有损伤作用,有雄性生殖毒性.  相似文献   

3.
Secretions produced by sebaceous and apocrine glands of cervids may be important in identifying individuals, establishing dominance, and signaling sexual readiness. The secretions from these glands are transferred to the hair for both lubrication and scent communication via forehead rubbing. We collected hair samples from the forehead and back of 10 male white-tailed deer (Odocoileus virginianus) of various ages and analyzed them with gas chromatography–mass spectrometry to determine age-related differences. Fifty-seven compounds were identified, including alkanes, arenes, aldehydes, ketones, aliphatic alcohols, terpenes, terpene alcohols, and phenols. Although forehead apocrine glands of dominant deer become more active during the breeding season, we found that concentrations of eight compounds found on the forehead hair were higher in subordinate deer, while only one was higher in dominant deer. Subordinate deer may have higher concentrations of these compounds because they rub less frequently than dominant deer. Additionally, only five forehead hair volatiles differed in concentration from those taken from the back hair. This seems to indicate that an increase in forehead glandular activity may take place concurrently with an increase in general integumentary glandular activity. The variation in hair volatiles among individuals also may be indicative of an individual-specific odor that could aid in identification.  相似文献   

4.
In this paper we report the stepwise preparation and the characterization of new unsymmetrical monoanionic Ru(III) dinuclear compounds, [NH(4)][{trans-RuCl(4)(Me(2)SO-S)}(mu-L){mer-RuCl(3)(Me(2)SO-S)(Me(2)SO-O)}] (L = pyz (1), pym (2)). By a similar synthetic approach we also prepared new mixed-valence Ru(III)/Ru(II) dinuclear compounds of formula [NH(4)][{trans-RuCl(4)(Me(2)SO-S)}(mu-pyz){cis,cis,cis-RuCl(2)(Me(2)SO-S)(2)(CO)}] (L = pyrazine (pyz, 3), pyrimidine (pym, 4)). Moreover, we describe the chemical behavior of compounds 1-4 in physiological solution, also after complete reduction (with ascorbic acid) to the corresponding Ru(II)/Ru(II) species. Overall, the chemical behavior of 1 and 2 after reduction resembles that of the corresponding dianionic and neutral dinuclear species, [{trans-RuCl(3)(Me(2)SO-S)}(2)(mu-L)](2-)and [{mer-RuCl(3)(Me(2)SO-S)(Me(2)SO-O)}(2) (mu-L)]. On the other hand, the mixed-valence dinuclear compounds 3 and 4, owing to the great inertness of the cis,cis,cis-RuCl(2)(Me(2)SO-S)(2)(CO)(1/2mu-L) fragment, behave substantially like the mononuclear species [trans-RuCl(4)(Me(2)SO-S)(L)](-) in which the terminally bonded L ligand can be considered as bearing a bulky substituent on the other N atom.  相似文献   

5.
Several new methods for the synthesis of TiPO4 are described. Crystalline phosphate compounds containing boron and titanium in a single III or mixed (III, IV) oxidation states have been synthesized and identified by X-ray diffraction. An additional family of phosphate compounds containing only Ti(III, IV) has also been synthesized and identified. All the compounds exhibit attractive colors, e.g., bright green, blue, purple, and black, and are stable at room temperature in air and in boiling water.  相似文献   

6.
Colloidal dispersions of uniform spherical particles of yttrium basic carbonate and rodlike particles of yttrium ammine carbonate were prepared by aging at elevated temperatures yttrium salt solutions in the presence of urea. Different composition and morphology were achieved by altering the aging temperature and time. Coprecipitation in mixed solutions of yttrium(III) and cerium(III) salts under similar experimental conditions yielded composite spherical particles of basic carbonate. The content of the two metals in the solids followed closely the initial composition of the reacting solutions. On calcination all prepared solids converted to their corresponding oxides while retaining their particle morphology. The so-prepared powders were characterized by various techniques.  相似文献   

7.
Raman spectroscopic and conductivity studies show that pyridinium derivatives of the TlCl52⊖, TlCl63⊖ and Tl2Cl93⊖ species dissociate in ethanol solution to yield the TlCl4 ion, but the [(C2H5)4N]2TlCl5 salt does not dissociate further and behaves like a 2:1 electrolyte.  相似文献   

8.
The rhodium(III)‐catalyzed oxidative olefination of 2‐aryloxazolines is described and has been employed for the synthesis of olefin‐oxazoline ligands (OlefOx). The highly modular synthesis starting from readily available 2‐aryloxazolines can be performed under an atmosphere of air as the terminal oxidant with catalytic amounts of copper(II)‐acetate.  相似文献   

9.

Abstract  

Three novel chiral salen-like schiff base ligands and their Mn(III) complexes containing different amino acid unit have been synthesized and characterized. Asymmetric epoxidation reactions show these complexes are effective catalysts for the chromenes with buffer NaOCl as terminal oxidant and pyridine N-oxide as co-catalyst in the presence of ionic liquid. Good-to -excellent enantioselectivity and acceptable yields can be obtained under optimum reaction conditions. Catalyst 4c gives the highest ee (95%) for 6-chloro-2,2-dimethylchromene among these catalytic performances. Furthermore, compared the enantioselectivity of catalyst 4c with the other two catalysts 4a and 4b, the positive experimental results suggest that the steric effect of the ligands plays an important role in the asymmetric catalysis.  相似文献   

10.
The content of the sternal gland secretion from four male koalas (Phascolarctos cinereus) was analyzed using gas chromatography–mass spectrometry. Volatile fatty acids, aldehydes, ketones, mono- and sesquiterpenes were identified, together with various volatile nitriles and oximes, some of which had not previously been described from any mammalian skin gland. Benzyl cyanide and phenylacetaldehyde oxime were identified as major components of the secretions, together with smaller amounts of the novel 3-methylthiopropanal oxime. The relative abundance of the identified compounds was highly variable between individuals and the scent composition was found to be partly determined by the scent of surrounding conspecifics. Principal component analysis revealed a high similarity between related individuals.  相似文献   

11.
The complexes [Ru([9]aneS(3))(dppz)Cl]Cl 1 and [Ru([12]aneS(4))(dppz)]Cl(2)2 ([9]aneS(3) = 1,4,7- trithiaciclononane and [12]aneS(4) = 1,4,7,10-tetrathiaciclododecane) were synthesised and fully characterised. These complexes belong to a small family of dipyridophenazine complexes with non-polypyridyl ancillary ligands . Interaction studies of these complexes with CT-DNA (UV/Vis titrations, steady-state emission and thermal denaturation) revealed their high affinity for DNA . Intercalation constants determined by UV/Vis titrations are of the same order of magnitude (10(6)) as other dppz metallointercalators, namely [Ru(II)(bpy)(2)dppz]S(2+). Differences between l and2 were identified by steady-state emission and thermal denaturation studies . Emission results are in accordance with structural data, which indicate how geometric distortions and different donor and/or acceptor ligand abilities affect luminescence. The possibility of noncovalent interactions between ancillary ligands and nucleobases by van der Waals contacts and H-bridges is discussed . Furthermore, complex l undergoes aquation under intra-cellular conditions and an equilibrium with the aquated form l' is attained . This behaviour may increase the diversity of available interaction modes.  相似文献   

12.
The ruthenium(III) complex Hlnd trans-[RuCl(4),(ind)(2)], with two trans-standing indazole (ind) ligands bound to ruthenium via nitrogen, shows remarkable activity in different tumor models in vitro and in vivo. The solvolysis of the complex trans-[RuCl(4),(ind)(2)](-) has been investigated by means of spectroscopic techniques (UV/vis, NMR)in different solvents. We investigated the indazolium as well as the sodium salt, the latter showing improved solubility in water. In aqueous acetonitrile and ethanol the solvolysis results in one main solvento complex. The hydrolysis of the complex is more complicated and depends on the pH of the solution as well as on the buffer system.  相似文献   

13.
Four novel Cr(III) complexes, Bis(ethylenediamine-κ2N,N′)(R-SA-κ2O,O′)chromium(III) chloride (H2SA = salicylic acid, R = 5-F, 5-Cl, 5-Br, 4-CH3 ethylenediamine = en) have been synthesized and three of them are determined by X-ray crystallography. The competition reaction with EDTA and apoovotransferrin (apoOTf) was monitored by UV–Visible (UV–vis) and fluorescence spectra at 37 °C. The reaction with EDTA is only a simple competitive process and no specific selectivity was observed (kEDTA/F410 = 4.07 × 10?3–4.37 × 10?3 M?1 s? 1). While for the reaction with apoOTf, an instable intermediate species (R-SA)–Cr(III)–OTf forms (kOTf/F336 = 1.70 × 10? 1–2.08 × 10?1 M?1 s? 1), where R-SA2? act as the role of synergistic anion. The intermediate is instable and the R-SA2? ligand will then be released with the rate constants of 1.17 × 10? 1 (5-F-SA2?)  1.01 × 10? 1 (4-CH3-SA2?) > 3.19 × 10? 2 (5-Cl-SA2?) > 3.25 × 10? 3 (5-Br-SA2?) M?1 s? 1. The substitutive groups R on SA have positive influence on charge density of O donor atom, which directly affect the stability of the (R-SA)–Cr(III)–OTf intermediate.  相似文献   

14.
以同多钼酸盐[Mo_8O_(26)]~(4-)为建筑块和柔性配体构筑二维网络超分子化合物:[H_2(bpp)_2][Mo_8O_(26)](1),通过单晶X射线衍射、元素分析对化合物1的结构进行了表征。  相似文献   

15.
16.
Blends stand out as simple and cheap materials with unique properties. The miscibility of blends formed by bisphenol-A polycarbonate (PC) with poly(methyl methacrylate) (PMMA) doped with europium (III) acetylacetonate have been studied by differential scanning calorimetry (DSC), infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and photoluminescent (PL) spectroscopy. DSC studies demonstrated that undoped PC/PMMA blends obtained by precipitation method present one glass transition temperature, evidencing their apparent miscibility. FTIR spectra revealed synergic effects in the PC/PMMA system as well as the incorporation of the Eu3+ complex. TGA analysis suggested that the Eu3+ complex remains preferably in the PC micro-phase. SEM analysis showed that europium (III) acetylacetonate is homogeneously distributed within the blend and PL spectra evidenced the photoluminescence of Eu3+ incorporated into the blend.  相似文献   

17.
18.
The adsorption behavior of Eu(III) onto silica surface, which was partially coated with Fe(III) or Ti(IV), was investigated to determine Fe(III) or Ti(IV) effects on the surface reaction of lanthanides on mineral surfaces in groundwater. Compared with a parallel uncoated silica, the Fe(III)-coated silica did not enhance the adsorption of Eu(III). However, enhanced adsorption of Eu(III) on the Ti(IV)-coated silica was observed by increasing the amount of Ti(IV) on the silica surface.  相似文献   

19.
The polymerization of styrene at 60°C initiated by 2,2′-azobisisobutyronitrile (AIBN) was studied in N,N-dimethylformamide (DMF) in the presence of tris-(bathophenanthroline)iron(III) complex, [Fe(bathophen)3]3+. The complex was prepared in situ by mixing hexakis(N,N-dimethylformamide)iron(III) perchlorate with bathophen-anthroline (systematic IUPAC nomenclature: 4,7-diphenyl-1,10-phenanthroline) in the molar ratio of 1 : 3. The equilibrium constant for was 3.12×103 L3 mol−3. The transfer constant for bathophenanthroline was found to be 0.38 ± 0.01 for the styrene/DMF system at 60°C. Mean velocity constant at 60°C for interaction of polystyryl radical with [Fe(bathophen)3]3+ was 3.73× 104 L mol−1 s−1. © 1996 John Wiley & Sons, Inc.  相似文献   

20.
The α-(1,2) fucosyltransferases (Fut1 and Fut2) and α-(1,3) fucosyltransferases (Fut4, Fut9) are responsible for the synthesis of Lewis X (LeX) and Lewis Y (LeY) conjugated to glycoproteins. We recently reported that these fucosyltransferases were differentially expressed in the reproductive tract of male mouse. Here, we studied the effect of androgen on fucosyltransferase expression through the use of mouse castration models. We found that Fut1 mRNA and Fut4 mRNA were upregulated, while Fut2 mRNA and Fut9 mRNA were downregulated by androgen in the caput epididymis. However, in the vas deferens and prostate, only Fut4 mRNA and Fut2 mRNA were respectively upregulated following exposure to androgen. In the seminal vesicle, all fucosyltransferases, with the exception of Fut9, were upregulated. We identified the androgen receptor binding sites (ARBSs) of Fut2, Fut4 and Fut9 in the caput epididymis. Luciferase assay for these ARBSs is able to provide an indication as to why Fut4 and Fut9 are differently expressed and regulated by androgen, although they catalyze the same α-(1,3) fucose linkage. Our study showed that androgen could differentially regulate the expression of these fucosyltransferases and provided an insight into the characteristic distribution of each fucosyltransferase responsible for LeX/LeY biosynthesis in the male reproductive tract.  相似文献   

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