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1.
2.
3, 5-二氢-4H-咪唑啉-4-酮的合成   总被引:1,自引:0,他引:1  
通过膦亚胺(2)与芳基异氰酸酯的aza-Wittig反应得碳二亚胺(3),再应用3与亲核试剂的成环反应制得了8个2-氨基取代咪唑啉酮的新衍生物5a~5h。探讨了碳二亚胺3与不同亲核试剂反应的活性。  相似文献   

3.
Some novel unsaturated five-membered organophosphorus heterocyclic compounds, 2-(p-toluenesulfonamido)-4-phenyl-4, 5-dihydro-1H-1, 3, 4-diazaphosphole 4-oxides 8 have been synthesized by Mannich-type reaction of p-toluenesulfonylguanidine with phenyldichlorophosphine and ketones.  相似文献   

4.
Oxidation of 5-hydroxy-5, 6-dihydro-4H-1, 2, 5-oxadiazines leads to the formation of 6H-1,2, 5-oxadiazine-5-oxides. Acid treatment of 5, 6-dihydro-4H-1, 2, 5-oxadiazines and 6H-1, 2, 5-oxadiazine-5-oxides results in heterocyclic-ring contraction with the formation of imidazole 3-oxides and 1-hydroxyimidazole 3-oxides. The structures of the products are established by their spectral properties and confirmed by independent synthesis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1264–1266, September, 1970.  相似文献   

5.
2-Hetaryl-3-oxo-4-phthalimidobutyronitriles (and pentanonitriles) were obtained with high yields by C-acylation of hetarylacetonitriles with N-phthaloylglycine and -alanine chlorides respectively under the conditions of base catalysis. Hydrazinolysis of the phthaloyl protection in these compounds leads to the formation of 5-amino-4-hetaryl-2,3-dihydro-1H-3-pyrrolones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1783–1790, December, 2004.  相似文献   

6.
It has been established that interacting ethyl 2-arylhydrazono-4-arylthio-3-oxobutyrates with hydrazine, methylhydrazine, and phenylhydrazine forms 4-arylhydrazono-3-arylthiomethyl-4,5-dihydro-1H-1-R-pyrazolones.  相似文献   

7.
由四个5,6-二取代-3,4-二氢-2-吡啶酮经烷基化反应合成了九个未见文献报道的N-取代5,6-二取代-3,4-二氢-2-吡啶酮,并确定了它们的结构。  相似文献   

8.
The formation of 2,4-substituted 1,2-dihydro-4H-3, 1-benzoxazines from tertiary o-aminophenylcarbinols and carbonyl derivatives has been demonstrated by means of PMR and mass spectrometry. Interconversion of the six-membered heterocycle of the half-chair half-chair type has been established on the basis of the PMR data when identical substituents are present in positions 2 and 4. The cisarrangement of the protons in the H-C(2)-N-H fragment of the heterocycle has been determined. The general laws governing the initial fragmentation of 1,2-dihydro-4H-3, 1-benzoxazines under the effects of electron impact have been revealed.For Communication 4, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 101–108, January, 1990.  相似文献   

9.
4-Arylmethylidene-4,5-dihydro-3-phenylisoxazol-5-ones were synthesized by the convenient three-component reaction of ethyl benzoylacetate,hydroxylamine and aromatic aldehydes in the presence of pyridine.The target compounds were also obtained by the reaction between 3-phenylisoxazol-5-one and aromatic aldehydes at 105℃under solvent free condition.Yields of products depended considerably on the aldehyde used.  相似文献   

10.
The title compound 3 was obtained during the rearrangement of isoxazol-5-yl hydrazine 1 to 1-aminopyrazolone 2 at 115°. X-ray analysis of the corresponding benzylidene derivative allowed us to achieve the structure assignment.  相似文献   

11.
Various 8-hydroxy-5-deazaflavin derivatives were synthesized as the model compounds of coenzyme F420-These compounds oxidized benzylamine to benzaldehyde more efficiently than the corresponding 8-unsubstituted 5-deazaflavins.  相似文献   

12.
The synthesis of 3, 4-dihydro-1H-benzothiin-3-one and its selenium and tellurium analogs is reported from o-bromomethylphenylacetyl chloride and sodium hydrogen chalcogenates, via phase-transfer catalysis.  相似文献   

13.
Three-component reaction of arylsulfonamides,dialkyl acetylenedicarboxylates,and ethyl chlorooxoacetate promoted by triphenylphosphine and triethylamine provides a sufficient route for the synthesis of dialkyl N-(arylsulfonyl)-4-ethoxy-5-oxo-2,5-dihydro -1H-pyrolle-2,3-dicarboxylates in good yields.  相似文献   

14.
15.
Zhang  Dawei  Ren  Lu  Liu  Ailing  Zhang  Yumin  Lv  Yang  Gu  Qiang 《Research on Chemical Intermediates》2022,48(3):983-1001
Research on Chemical Intermediates - An efficient synthesis of 1,3,5-trisubstituted-1H-pyrazoles was developed via cyclocondensation in 78–92% yields starting from α,β-unsaturated...  相似文献   

16.
The proton magnetic resonance spectrum of 4-t-butyl-5,6-dihydro-4H-pyran has been analyzed with the aid of the paramagnetic shift reagent Eu(fod)3. All hydrogen-hydrogen spin-spin coupling constants are reported and a conformation is suggested which is consistent with these data.  相似文献   

17.
The known but long-neglected compound HODhat was shown to be in certain situations a useful peptide coupling additive. Uronium and phosphonium salts with HODhat built into the system were also useful stand-alone coupling reagents. Comparisons with related additives and coupling reagents showed that the new systems were sometimes more and sometimes less effective than previously described systems in the case of stepwise and segment couplings. Applications to assembly of the model decapeptide ACP showed that HDATU was far more effective than HDTU and more effective than HATU under some conditions.  相似文献   

18.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1425–1426, October, 1989.  相似文献   

19.
A series of novel 5-phenyl-3-(2,2':5',2″-terthien-5-yl)-4,5-dihydro-lH-pyrazolines were synthesized in this report. Their photoactivated cytotoxicities on the 5podoptera litura (SL) cell line were evaluated using the MTT method. It was noticed that the inhibitory activities of all the conjugates was enhanced when irradiated with UV-A light. Compounds 4, 6 and 8 were found to be most effective with inhibition rates of 88.1%, 88.0%, and 90,5%, respectively, For compound B, the inhibition rate value was only slightly enhanced under the irradiation treatment (78.3%) compared to the dark treatment (74.8%). The relationship analysis between structure and activity showed that the middle thiophene ring played an important role on the inhibitory activities. It was shown that these compounds could be the potential candidates for new photoactivated pesticides.  相似文献   

20.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, p. 1696, December, 1989.  相似文献   

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