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1.
A. M. Shestopalov A. P. Yakubov D. V. Tsyganov Yu. M. Emel'yanova V. N. Nesterov 《Chemistry of Heterocyclic Compounds》2002,38(10):1180-1189
Substituted 6-aminopyrano[2,3-c]pyrazoles were synthesized by the two-component condensation of arylidenemalononitriles and substituted 5-pyrazolones or three-component condensation of aromatic aldehydes, malononitrile, and substituted 5-pyrazolones. It was established by X-ray crystallographic analysis that pyranopyrazoles exist in the 2H and not the 1H tautomeric form. 相似文献
2.
Fathy Abdel‐Kader Amer Metwally Hammouda Abdel‐Aziz Sayed El‐Ahl Bakr Fathy Abdel‐Wahab 《中国化学会会志》2007,54(6):1543-1552
Treatment of heterocyclic β‐ketonitriles 1a,b with hydrazine hydrate and phenylhydrazine afforded the hydrazine derivatives 2a‐d which cyclized in PPA into pyrrolo[3,4‐c]pyrazoles 3a‐d. Reaction of 1a,b with cyanoacetohydrazide furnished the cyanoacetyl pyrrolo[3,4‐c]pyrazoles 4a,b. The hydrazine 2c reacted with β‐diketone and β‐ketoesters to afford pyrazolyl‐pyrrolines 5‐7. Also the later hydrazine reacted with some D‐aldoses and aceteophenone to give the corresponding hydrazones 10‐12 and hydrazine carboxamide derivatives 15a,b respectively. 相似文献
3.
The reactivity of N1-alkylsulfonyl- and N1-arylsulfonyl-2′,3′,5′-tri-O-acetylinosine with benzylamine and with 15NH3, regarding the attack on C2, has been shown to be in the order CF3SO2 (Tf) > 2,4-(NO2)2C6H3SO2 (DNs) ? 4-NO2C6H4SO2 (pNs) ≈ C6F5SO2 (PFBs) > 2-NO2C6H4SO2 (Ns) ? CH3SO2 (Ms) > 4-CH3C6H4SO2 (Ts) > 2,4,6-(CH3)3C6H2SO2 (Mts). In spite of its intermediate reactivity, the Ns group is the most appropriate, since in this case the formation of by-products is minimised during the ring-opening and ring-closing steps of the process. Another advantage of the Ns group is thus disclosed. 相似文献
4.
E. V. Tretyakov S. E. Tolstikov G. V. Romanenko Yu. G. Shvedenkov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2005,54(9):2169-2181
A new approach to the synthesis of polyfunctional pyrazolyl-substituted nitronyl nitroxides was developed based on the presynthesized
pyrazole derivatives prepared by 1,3-dipolar cycloaddition. The structures of the resulting mono-and biradicals were confirmed
by X-ray diffraction.
Dedicated to Academician A. L. Buchachenko on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2105–2116, September, 2005. 相似文献
5.
1INTRODUCTIONPolarizedketenedithioacetalshavebeenex-tensivelyusedasbuildingblocksinorganicsyn-thesis,especiallyinthesynthesisofheterocycliccompounds[1~6].Pyrazoleanditsderivativesrepre-sentoneofthemostactiveclassesofcompoundspossessingwidespectraofbiologicalactivities.Overthepastfewyears,considerableevidenceshavebeenaccumulatedtodemonstratetheefficacyofpyrazolederivatives,suchasantibacterial[7],fun-gicidal[8],herbicidal[9],insecticidal[10]andotherbiologicalactivities[11,12].Uptonow,alarg… 相似文献
6.
Kh. Polvonov Q. Sabirov Kh. M. Shakhidoyatov 《Chemistry of Heterocyclic Compounds》2003,39(2):228-232
The reaction of 5-anilino(toluidino-, morpholino)-1,3,4-thiadiazoline-2-thiones at 80°C with allyl bromide and benzyl chloride in alcohol, acetonitrile or DMF in the presence of KOH and also with phenoxymethyloxirane in alcohol in the absence of base gives the corresponding novel allyl-, benzyl-, and 2-hydroxy-3-phenoxypropyl products substituted at the exocyclic S atom. Alkylation of the indicated thiones with benzyl chloride at 150-153°C in DMF in the presence of KOH occurs similarly. Under these conditions, allyl bromide forms alkylation products at the endocyclic N(3) atom as a result of an SN thio-Claisen rearrangement of the initially formed product which is allyl substituted at the exocyclic S atom. 相似文献
7.
Alkylation of 8-dimethylamino-1-methylamino-4-nitronaphthalene in the CD3I/KOH/DMSO system afforded a 4-nitro derivative containing the N(CD3)Me group in position 1. Direct proof of the structure of the intramolecular hydrogen bond in solutions of monoprotonated
4-R-1,8-bis(dimethylamino)naphthalenes was obtained for the first time. 1H NMR study revealed that the chelated NH proton is shifted to the N(8) atom for R = NO2 and NH3
+ and to the N(1) atom for R = NH2.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 159–162, January, 2006. 相似文献
8.
The γ-substituted β-diketonate 2,4-dioxo-3-pentyl 4-[4-(n-octyloxy)cinnamoyl]oxybenzoate 1 and its pyrazole and isoxazole derivatives (2 and 3 respectively) have been synthesized and characterized by the spectroscopic methods and elemental analysis. The mesogenic properties of these compounds have been studied by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). A monotropic nematic mesophase was observed for the β-diketonate 1, in contrast, the pyrazole 2 displays an enantiotropic smectic A and isoxazole 3 exhibits an enantiotropic nematic mesophase. The relationship between the structure and liquid crystalline properties has also been discussed. 相似文献
9.
E. G. Paronikyan S. N. Sirakanyan A. S. Noravyan 《Chemistry of Heterocyclic Compounds》2003,39(3):374-378
We have synthesized derivatives of pyrano(thiopyrano)[4,3-d]pyrazolo[3,4-b]pyridine and pyrazolo[3,4-c]isoquinoline, and we have also carried out some conversions with them. 相似文献
10.
The title compound (C25H24N4O3) has been prepared by the cyclocondensation of 5-amino-3-methyl-l-phenypyrazol, m-nitrobenaldehyde and dimedone in glycol under microwave irradiation without catalyst. The crystal structure was determined by single-crystal X-ray diffraction to be orthorhombic, space group Pbca with a=16.3331(10), b=13.8329(9), c=19.4163(12) A, V= 4386.8(5)A3, Z=8, Dc=1.298g/cm^3,μ=0.087 mm^-1, F(000)=1808, Mr=428.48, the final R=0.0519 and wR=0.1019. X-ray analysis revealed that the pyridine ring is of boat conformation and the six-membered ring fused with it adopts twist boat conformation. 相似文献