Comparison between antioxidant activity of 2,5-disubstituted 1,3,4-oxadiazoles containing heteroaromatic ring and aromatic ring at 2nd position
摘要:
A series of 4-[5-(substitutedphenyl)-1,3,4-oxadiazol-2-yl]-pyridine) and 2-[5-substitutedphenyl)-1,3,4-oxadiazol-2-yl]-benzenamine derivatives were synthesized from substituted esters and hydrazine hydrate in the presence of ethanol to give isonicotinic acid hydrazide and 2-aminobenzohydrazide followed by reaction with phosphorus oxychloride and various aromatic acids. All the compounds were tested for their in vitro antioxidant activity by 1,1-diphenyl-2-picryl hydrazyl (DPPH) method. Compounds containing aromatic group at 2nd position showed significant activity as compared to standard (ascorbic acid) which concludes that the presence of aromatic group increases the free radical scavenging activity.
intramolecular decarboxylative coupling reaction for the construction of 2-(1,3,4-oxadiazol-2-yl)aniline derivatives was developed from readily available isatins and hydrazides by virtue of electrochemistry. In this reaction, isatins were employed as amino-attached C1 sources, providing a variety of 2-(1,3,4-oxadiazol-2-yl)aniline derivatives with moderate to good yields.
A visible-light-induced synthesis of 2,5-disubstituted1,3,4-oxadiazoles from simple diketones and hydrazides with the assistant of the photocatalyst eosin Y catalyzed decarboxylation and cyclization under mild conditions has been discovered. The reaction tolerates a wide range of functional groups and gives a variety of valuable 1,3,4-oxadiazoles in moderate to good yields. Finally, a plausible reaction
Synthesis of 3-Aminoquinazolinones via a SnCl<sub>2</sub>-Mediated ANRORC-like Reductive Rearrangement of 1,3,4-Oxadiazoles
作者:Mohamed Elagawany、Lingaiah Maram、Bahaa Elgendy
DOI:10.1021/acs.joc.3c01973
日期:2023.12.15
Herein, we developed a new SnCl2-mediated ANRORC (addition of nucleophile, ring-opening, and ring-closure)-like rearrangement for the synthesis of 3-amino-2-substituted-quinazolin-4(3H)-one from 2-(2-nitrophenyl)-5-substituted-1,3,4-oxadiazole. The new method is solvent-dependent and features the use of a green solvent system (i.e., ethanol/water), high yields, and simple workup. The reduced product
在此,我们开发了一种新的SnCl 2介导的ANRORC(亲核试剂加成、开环和闭环)类重排,用于合成3-氨基-2-取代-喹唑啉-4(3 H )-one 2-(2-硝基苯基)-5-取代-1,3,4-恶二唑。新方法依赖于溶剂,具有使用绿色溶剂系统(即乙醇/水)、高产率和简单后处理的特点。将溶剂改为乙腈即可独家合成还原产物。
Reddy, P. S. N.; Reddy, P. Pratap, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1988, vol. 27, # 1-12, p. 763 - 765
作者:Reddy, P. S. N.、Reddy, P. Pratap
DOI:——
日期:——
REDDY, P. S. N.;REDDY, P. PRATAP, INDIAN J. CHEM. B, 27,(1988) N, C. 763-765