Aminoamidines

Reactions ofN-aryl- andN-methyl-amidines and -amides of 72u7m7707j4227/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-amino acids with RPCl₂ afford 4-aryl(methyl)imino and 4-oxo-1,3,2-diazaphospholanes. 4-Phenylimino-1,3,2-diazaphosphorinane was obtained in a similar way by the interaction of N(1), N(2)-diphenyl-72u7m7707j4227/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-anilinoisobutyramidine with PhPCl₂.For communication 5 see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1116–1121, June, 1993.     

Synthesis and cytotoxic properties of 7α-chloro-3-methyl-1,1-dioxoceph-3-ems, substituted with amide or keto group at position 4

7α-Chloro-3-methyl-1,1-dioxoceph-3-ems with amide or keto group at position 4 have been synthesized by structural modification of 7α-chloro-3-methyl-1,1-dioxoceph-3-em-4-carboxylic acid. Screening of these compounds for cytotoxic activity revealed compounds with specific activity against cancer cells in vitro, capable of effective inhibition of the growth of sarcoma S-180 in vivo. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, 1849–1859, December 2007.     

Die Kristallstruktur von KPdMIVF7 (MIV = Zr,Hf)

The Crystal Structure of KPdM^IVF₇ (M^IV = Zr, Hf) Blue single crystals of KPdZrF₇ are obtained by heating the binary fluorides in sealed Pt-tubes under dry argon (solid state reaction, T ≈? 720
76;C, t ≈? 14 d). The compound crystallizes orthorhombically in the space group Pnna-D75efbc-800b-4cc7-b4d9-c67d5d5d66e8/tex2gif-stack-2.gif"> (Nr. 52); lattice parameters are a = 1 132.3(5) pm, b = 797.5(2) pm, c = 639.8(1) pm; Z = 4 (Four cycle diffractometer data, AED2). According to [F₄PdF_2/1ZrF₅] distortet [PdF₆]-octaedra are connected with pentagonal-bipyramidal [ZrF₇]-polyhedra via two bridging F^?, resulting in [PdZrF₁₁]-groups. These [PdZrF₁₁]-groups built up a threedimensional-network with K⁺ in its spacings. KPdHfF₇ crystallizes isotypically (a = 1 136.1(3) pm, b = 796.4(2) pm und c = 638.8(1) pm; four cycle diffractometer data, AED2).     

芫花中芫花素的提取工艺与杀虫试验

芫花 (ＤａｐｈｎｅｇｅｎｋｗａＳｉｅｂ.ｅｔＺｕｃｃ.)属于瑞香科植物[1] ,芫花的浸取液对棉蛉虫、稻螟虫、菜青虫、班蝥等害虫具有较好的杀虫效果 ,且对人畜无害 ,是一种理想的无公害农药[2 ] 。为了提高药效 ,更好地开发这种无公害农药 ,本文对芫花中杀虫有效成分的提取工艺与杀虫效果进行了初步研究。1　实验部分1 1　试剂和仪器苯 ,氯仿和 95 %的乙醇均为分析纯 ;岛津ＵＶ -2 40型紫外可见分光光度仪 ;ＦＴ -80ＡＮＭＲ仪。1 2　实验方法芫花枝条干粉 1 5 0 0ｇ,加水 1 0 .0 0Ｌ煮沸 1 2小时 ,煮沸过程中陆续补加少量水分。将煮沸…     

Bis(benzoylpyridin-p-toluensulfonylhydrazido)nickel Ni(BPSH)2 · H2O — Beziehungen zwischen Struktur und Redox- bzw. Extraktionsverhalten heterocyclischer Sulfonamidochelate

Bis(benzoylpyridin-toluensulfonylhydrazido)nickel Ni(BPSH)₂ · H₂O — Relations between Structure, Redox, and Extraction Properties of Heterocyclic Sulfonamido Chelates The crystal structure of Ni(BPSH)₂ · H₂O was determined by x-ray diffraction: monoclinic, space group P21/c (Nr. 14); a = 15.077(4) 7;, b = 14.901(3) 7;, c = 16.335(3) 7;, β = 95.74(1)
76;. R = 0.047 for a total of 5564 observed reflexions. Ni(BPSH)₂ · H₂O has a distorted tetrahedral structure with two six-membered chelate rings, one of them with a boat from. The electron system of the building blocks CNN^? within the chelate rings approaches that of a diazallyl group. The result is a high electron density on the sp²-hybridized donor atom N^? and, as a consequence, a short Ni? N^?-distance (1.908 or 1.924 7;). The electronic properties of N^? also explain the high NH-acidity of the acid H(BPSH) (pk_s = 9,51 in 75 per cent dioxane) and the ligand field strength of BPSH^? which is low compared to that of other bidentate sulfonamido ligands and which is reflected in the paramagnetism of Ni(BPSH)₂ · H₂O. The redox behavior of metal chelates of the type, which is represented by Ni(BPSH)₂ · H₂O, is caused by a building block of the ligand which is also present in bipyridyl or in the 1,4-diaza-1,3-dienes. The central atoms M¹¹ have only the function of interference factors.     

Theoretical study of structure and stability of h+x (h2)n clusters

The ion clusters H⁺X· (H₂)_n (X = N₂, CO, O₂ and H₂ andn = 0, 1, 2) are investigated by means of SCF and CI computations in a double-zeta plus polarization gaussian basis It is found that hydrogen molecules attack the proton of H⁺X perpendicularly. The calculated stabilization energies are in agreement with experimental values of δH⁰.     

Theoretical Investigations of the Inclusion Processes of (4-tert-butylphenyl) (3-sulfonatophenyl) (phenyl) Phosphine in β-Cyclodextrin

Quantum mechanical calculations on the (4-tert-butylphenyl)(3-sulfonatophenyl) (phenyl) phosphine/7ju3ew/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin inclusion complex werecarried out using semi-empirical calculations. Inclusion process pathways are describedand the most probable structures of the 1:1 complex are sought through a global potentialenergy scan. The calculations suggest that the most stable structure is obtained whenthe aromatic ring bearing the tert-butyl group is includedinto the hydrophobic cavity of the 7ju3ew/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin from theside of the primary hydroxyl groups.     

Conformational studies of poly(N5-Ω-hydroxyalkyl-L-glutamine)s in reversed micelles

The molecular conformations of poly(N⁵-dihydroxyethylaminopropyl-L-glutamine) and poly(N⁵-dihydroxyethyl-L-glutamine) were investigated in reversed micelles of AOT as well as in aqueous solutions. Both poly(7/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-amino acid)s assume disordered structures in pure water. The conformation of poly(N⁵-dihydroxyethylaminopropyl-L-glutamine) transits into7/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-helix in the reversed micelles as the molar ratio of water to AOT (w₀=[H₂O]/[AOT]) becomes smaller. A similar conformational transition was also observed in aqueous solutions when a certain amount of AOT was added. Under these conditions, however, poly(N⁵-dihydroxyethyl-L-glutamine) did not undergo a conformational transition into7/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-helix.     

荧光法测定铍的研究

研究了新荧光试剂 7 [(2 ,4 二羟基 5 羧基苯 )偶氮 ] 8 羟基喹啉 5 磺酸 (DHCPAQS)与铍络合的反应条件及测定方法。在pH 8.0硼砂体系的缓冲介质中形成R∶Be =2∶1型的强荧光配合物 ,其λex/λem=362nm/ 497nm。铍含量在 0～ 0 .2 0mg·L- 1范围内呈线性关系 ,检出限为 2 .2×10 - 6 mol·L- 1。该方法应用于合金样中痕量铍的测定 ,结果满意。     

Stereoselective synthesis of Nuphar quinolizidine alkaloid, (−)-deoxynupharidine

A stereoselective synthetic route to Nuphar quinolizidine alkaloid, (−)-deoxynupharidine, was established by employing reductive carbon-nitrogen bond cleavage, followed by simultaneous recyclization of a proline derivative with samarium diiodide, and an intramolecular ring-closing metathesis, as the key steps.