Home About us Contact
|
Home About us Contact | ||
|
|
||
Active Methylene Reagents (active + methylene_reagent)
Selected AbstractsHeterocyclic synthesis with ethyl ,-(3-carbamoyl-4,5,6,7-tetrahydrobenzo[b]thiophen-2-ylhydrazono)acetates: An expeditious synthetic approach to polyfunctionally substituted pyran, pyridine, and pyridazine derivativesHETEROATOM CHEMISTRY, Issue 4 2004Rafat M. Mohareb Ethyl ,-(3-carbamoyl-4,5,6,7-tetrahydrobenzo[b]thiophen-2-ylhydrazono)acetates 1 were prepared and established as previously described by our research group. Their reactivity toward a variety of active methylene reagents was studied to give pyran, pyridine, and pyridazine derivatives. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:300,306, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20019 [source] Ethyl {4-[2-(saccharin-2-yl)acetylsulfamoyl]phenylazo}cyanoacetate in the synthesis of polyfunctionally heteroaromatic derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2009A. A. Aly An efficient and direct one-pot reaction of ethyl saccharinylcyanoacetate derivative 3 with a variety of active methylene reagents and nitrogen nucleophiles afforded novel series of polyfunctionally substituted heteroaromatic derivatives 5,13, respectively. The pyrazole derivative 13 was seemed to be the excellent precursors for the synthesis of pyrazolo[1,5-a]pyrimidine derivatives 14,24. The antimicrobial screening of some synthesized products was evaluated against some selected bacteria and fungi. The structures of the synthesized derivatives were established by elemental and spectral data. J. Heterocyclic Chem., (2009). [source] ,-Oxoanilides in heterocyclic synthesis: An expeditious synthesis of new polyfunctionally substituted pyridine and pyrazole derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2008A. M. Hussein 3-Oxo- N -{4-[(pyrimidin-2-ylamino)sulfonyl]phenyl}butanamide 3 was condensed with (DMF-DMA) in refluxing dry dioxane to yield branched structure 4 not its linear isomeric 5. Compound 4 readily reacted with active methylene to yield compounds 8a-c, 14, 17 and 20 respectively. Also enaminone 4 reacted with phenyl hydrazine giving 24 and 25. In contrast, when compound 4 reacted with hydrazine hydrate in the same experimental conditions pyrazole derivative 27 was obtained. Furthermore, condensation of anilide 3 with triethylorthoformate in refluxing acetic anhydride afforded the ethoxy methylene derivative 28. On the other hand, compound 28 was reacted with active methylene reagents, and hydrazines to afford the products identical in all respects (mp., mixed mp., and spectral data) with those corresponding to compounds 6-27 respectively. Similarly, compound 3 was reacted with hydrazine hydrate to afford the reaction product 29. Also, compound 3 reacted with cyanoacetamide in refluxing ethanolic pipridine solution to yield the pyridine derivative 30. Finally, 3 reacted with hydroxylamine hydrochloride in refluxing ethanol/sodium acetate solution to yield the acyclic oxime derivative 31. [source] The condensation of active methylene reagents with salicylaldehyde: Novel synthesis of chromene, azaanthracene, pyrano[3,4-c]chromene and chromeno[3,4- c]pyridine derivativesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2004Tarek M. Abu Elmaati On heating of the cyanoacetic acid cyclopentylidene hydrazide 1 with salicylaldehyde in the presence of bases the azaanthracene derivative 6 was formed. Also, reaction of 3 with malononitrile and ketones 10a,b afforded the pyrano[3,4- c]chromene 9 and chromeno[3,4- c]pyridine 11 respectively. A mechanism for these reactions is proposed. [source] | ||||||||||