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501.
本文合成了题头所示大环配体,并制备了它的十四种镧系元素(La~Lu,Pm除外)固体配合物。用元素分析,DTA-TG,红外光谱以及电导测定等手段研究了这些化合物的组成和性质.基于这些分析结果可建议配合物化学式为Ln(H_2L)(NO_3)_3·nH_2O。  相似文献   
502.
The crystal and molecular structure of the title compound (Me2-TPzT) has been determined by X-ray analysis. The observed molecular conformation presents the nitrogen atoms of three pyrazole rings in the same relative positions. The molecules are joined through intermolecular contacts forming chains that are arranged in a distorted hexagonal symmetry. Two complexes containing this ligand have been prepared: [{Pd(en)}3(Me2-TPzT)](PF6)6 and [{Ag(PPh3)}3(Me2-TPzT)](ClO4)3, which, due to their insolubility, have been characterized only by microanalysis, IR, 1H NMR and, in the latter case, by mass spectrometry.  相似文献   
503.
Nitropyrazoles     
A method of synthesizing nitro derivatives of lH,4H-pyrazolo[4,3-c]pyrazole is developed, and some of its transformations are studied. 3-Methyl-6-nitro-, 3-carboxy(methoxy-carbonyl, carbamoyl)-6-nitro-, 3-amino-6-nitro-, 3-nitro-, 3,6-dinitro-, 1,4-diacetonyl-3,6-dinitro-, and lH,4H-3-aminopyrazolo[4,3-c]pyrazoles were obtained from 1H,4H-3 -methylpyrazolo[4,3-c]pyrazole. Unsubstituted 1H,4H-pyrazolo[4,3-c]pyrazole, the first member of this series, was obtained for the first time. The compounds prepared were characterized by1H,13C,14N, and15N NMR spectroscopy. NH-Acidity and basicity of the series of pyrazolo[4,3-c]pyrazoles synthesized is studied and the effect of the fused pyrazole ring on these properties is examined.Deceased March 18, 1989.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1108–1113, June, 1993.  相似文献   
504.
新型吡唑并嘧啶并吡唑三元稠合化合物的合成   总被引:1,自引:0,他引:1  
刘莹  张晓弘  金桂玉 《中国化学》2005,23(2):182-184
Novel fused heterotricyclic compounds 3—6 containing two different dipyrazolopyrimidine framework were prepared from 1a—1d. The reaction of 1 with K2CO3 in DMSO or NaH in DMF led to the formation of 2 or 3, respectively, which reacted further to afford 6 or 5, respectively.  相似文献   
505.
Unexpected 4,4′‐dipyrazolomethylidene ( 7 ), 4‐amino‐3a‐bromo‐3‐methyl‐1‐phenylpyrazolo[3,4‐b]pyridin‐6‐thione ( 9 ), 4,4′‐dipyrazolyl ( 18 ), ethyl 4‐(3‐methyl‐1‐phenylpyrazole‐4‐yl)fuoro[2,3‐c]pyrazole‐4‐carboxylate ( 25 ), as well as the expected fuoro[2,3‐c]pyrazole derivatives ( 15 ), ( 20 ) and ( 28 ) were isolated from a one‐pot reaction of 4‐bromo‐3‐methyl‐1‐phenylpyrazole ( 1 ) with some readily available reagents.  相似文献   
506.
Summary Carbon disulfide added to the active methylene group in1 in basicDMF at room temperature to yield the non-isolable 1:1 adduct2.In-situ cyclization of the latter with some -bromo compounds afforded the corresponding polyfunctionally substituted thiophenes5. The reactivity of5 towards a variety of reagents was studied. Chemical and spectroscopic evidences for the structure of the new compounds are provided.
Reaktion von Schwefelkohlenstoff mit 3-Amino-2-cyano-2-penten-1,5-carbonsäurediethylester: Eine einfache Synthese polyfunktionell substituierter Thiophene und ihrer kondensierten Derivate
Zusammenfassung Die Addition von Schwefelkohlenstoff an die aktive Methylengruppe von1 in basischemDMF bei Zimmertempeatur ergab das nicht isolierbaren 1:1-Addukt2.In situ-Cyclisierung des letzteren mit einigen -Brom-Verbindungen führte zu den entsprechenden polyfunktionell substituierten Thiophenen5. Die Reaktivität von5 gegenüber verschiedenen Reagentien wurde untersucht. Die Strukturen der neuen Verbindungen wurden chemisch und spektroskopisch abgesichert.
  相似文献   
507.
Reaction of 2,4,6-trimethylaniline with acrylic and itaconic acids gives the corresponding N-substituted =alanines which can be converted to derivatives of tetrahydropyridone, dihydropyrimidinedione, and 4-carboxy-2-pyrrolidinone. Bromination of the aromatic substituent in the synthesized heterocycles has been carried out.Kaunas Technological University, Kaunas 3028, Lithuania Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 951–954, July, 2000  相似文献   
508.
The influence of inorganic anions: perchlorate, chloride, sulphate, and hydrogen sulphate on the acid-base and tautomeric equilibria of 4-aminoazobenzene (AAB) and its N-ethyl (EAAB), N,N-diethyl (DEAAB), and N-phenyl (PhAAB) derivatives was investigated by UV-spectrophotometry in 80%:20% vol. ethanol:water system. The possible equilibrium models were evaluated by means of the nonlinear confluence analysis program STOICHIO in order to explain the observed dependence of the electronic spectra on acid and salt concentration. It was found that all the anions considered form 1:1 associates with both ammonium and azonium tautomers of the protonated aminoazobenzenes. The corresponding association constants were generally about one order of magnitude greater for SO 4 2– than for the univalent ions. The azonium species were found to form more stable associates in all the cases except SO 4 2– , which explains the observed shift of the tautomeric equilibrium towards the azonium form on increasing the mineral acid or salt concentration. Based on the obtained values of the molar absorption coefficients all but the PhAAB associates were found to be of the ionic pair type, with proton transfer taking place only in the last case. This was due to the greater basicity SO 4 2– , compared with PhAAB. The association constant values obtained are discussed in terms of the tendency of the anions studied to associate, as well as in terms of the effect of solvation on the stability of the ionic pairs formed.  相似文献   
509.
1-Benzoyl-5-hydroxy-pyrazoline 1 was prepared and its reactions with ketenes, prepared in situ from the corresponding acid chlorides 3a-3d and the mixed anhydride 4, were studied. In all cases the 1,3,4-oxadiazoles 5 were isolated. In the case of compounds 3c and 3d a second diastereomeric oxadiazole 6 was obtained. In the case of 3a,3b and 4, an interesting aroyl migration product 7 was isolated. Structural assignments of the derived compounds were established by analysis of their IR, MS and NMR spectra (1H, 13C, COSY, NOESY, HETCOR and COLOC). The proposed reaction mechanism is supported by semi-empirical (AM1) MO calculations.  相似文献   
510.
以2,4-二氯嘧啶为起始原料, 利用两个氯原子的活性差异, 经4-吡唑基-2-氯嘧啶合成了一系列4-吡唑基-2-芳氧基嘧啶类化合物, 通过1H NMR和元素分析对所合成的化合物进行了结构表征. 初步生物活性测定结果表明, 所合成的化合物都表现出一定的除草活性. 当嘧啶环2位的氯原子被芳氧基取代后, 化合物的除草活性均有不同程度的提高, 例如5c4a相比, 100 μg•mL-1时化合物对油菜的抑制率由15.7%提高到85.4%, 对稗草的抑制率由原来的11.6%提高到84.0%.  相似文献   
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