60027-80-7Relevant academic research and scientific papers
Secondary Interactions Arrest the Hemiaminal Intermediate to Invert the Modus Operandi of Schiff Base Reaction: A Route to Benzoxazinones
Patel, Ketan,Deshmukh, Satej S.,Bodkhe, Dnyaneshwar,Mane, Manoj,Vanka, Kumar,Shinde, Dinesh,Rajamohanan, Pattuparambil R.,Nandi, Shyamapada,Vaidhyanathan, Ramanathan,Chikkali, Samir H.
, p. 4342 - 4351 (2017/04/28)
Discovered by Hugo Schiff, condensation between amine and aldehyde represents one of the most ubiquitous reactions in chemistry. This classical reaction is widely used to manufacture pharmaceuticals and fine chemicals. However, the rapid and reversible formation of Schiff base prohibits formation of alternative products, of which benzoxazinones are an important class. Therefore, manipulating the reactivity of two partners to invert the course of this reaction is an elusive target. Presented here is a synthetic strategy that regulates the sequence of Schiff base reaction via weak secondary interactions. Guided by the computational models, reaction between 2,3,4,5,6-pentafluoro-benzaldehyde with 2-amino-6-methylbenzoic acid revealed quantitative (99%) formation of 5-methyl-2-(perfluorophenyl)-1,2-dihydro-4H-benzo[d][1,3]oxazin-4-one (15). Electron donating and electron withdrawing ortho-substituents on 2-aminobenzoic acid resulted in the production of benzoxazinones 9-36. The mode of action was tracked using low temperature NMR, UV-vis spectroscopy, and isotopic (18O) labeling experiments. These spectroscopic mechanistic investigations revealed that the hemiaminal intermediate is arrested by the hydrogen-bonding motif to yield benzoxazinone. Thus, the mechanistic investigations and DFT calculations categorically rule out the possibility of in situ imine formation followed by ring-closing, but support instead hydrogen-bond assisted ring-closing to prodrugs. This unprecedented reaction represents an interesting and competitive alternative to metal catalyzed and classical methods of preparing benzoxazinone.
Microwave-assisted synthesis, characterization, and antimicrobial activity of some odorant Schiff bases derived from naturally occurring carbonyl compounds and anthranilic acid
Kaushik, Prasoon Kumar,Varshney,Kumar, Pawan,Bhatia, Pallavi,Shukla
supporting information, p. 2053 - 2062 (2016/12/09)
Nine odorant Schiff bases, namely 2-(4-methoxybenzylideneamino) benzoic acid, 2-(benzylideneamino) benzoic acid, 2-(3-phenylallylidene amino) benzoic acid, 2-(3,7-dimethyloct-2,6-enylideneamino) benzoic acid, 2-(3,7-dimethyloct-6-enylideneamino) benzoic a
Synthesis of some newer derivatives of 2-amino benzoic acid as potent anti-inflammatory and analgesic agents
Kumar, Ashok,Bansal, Deepti,Bajaj, Kiran,Sharma, Shalabh,Archana,Srivastava
, p. 5281 - 5291 (2007/10/03)
Diazotization of N-benzylidene anthranilic acids 1a-1n at pH 9 yielded N-[α-(phenylazo) benzylidene] anthranilic acids 2a-2n and at pH 3 yielded N-benzylidene-5-(phenylazo) anthranilic acids 3a-3n. When compounds 3a-3n were treated with thioglycolic/thiolactic acid in the presence of anhydrous ZnCl 2, 2-(4-oxo-2-phenylthiazolidin-3-yl)-5-(phenylazo) benzoic acids 4a-4n were afforded. The newly synthesized compounds were screened for their anti-inflammatory and analgesic activities and were compared with standard drugs, aspirin and phenylbutazone. Out of the compounds studied, the most active compound 4n showed more potent activity than the standard drugs at all doses tested.
Synthesis of 2-(o-Arylideneaminophenyl)-3-(5-alkyl-1,3,4-thiadiazol-2-yl)quinazolin-4-ones as Potential Anthelmintic Agents
Shukla, J. S.,Singh, Mithilesh,Rastogi, Renu
, p. 306 - 307 (2007/10/02)
A series of 2-(o-arylideneaminophenyl)-3-(5-alkyl-1,3,4-thiadiazol-2-yl)quinazolin-4-ones (13-41) have been synthesised and screened for their cestodicidal activity against Hymenolepis nana infection in rats.Compound 19 has been found to be the most active member of the series showing 77.2percent clearance of infection at a dose of 250 mg/kg given for 3 days.
