Phenylglyoxal

Abstract

(A) Eftekhari-Sis et al. reported the synthesis of novel 2-aryl-4-chloro- 3-hydroxy-1H-indole-5,7-dicarbaldehydes via Vilsmeier-Haack reaction starting from phenylglyoxal. 5 (B) To the best of our knowledge, there are no reports in the literature for the formation of pyrrole-3-ol derivatives via condensation of ketones with phenylglyoxal. In this paper, a simple method for the synthesis of new N-alkyl(aryl)-2,4-diaryl-1H-pyrrole-3-ol derivatives via aldol reaction of 1-(4-methoxyphenyl)propan-2-one with phenylglyoxal in the presence of a catalytic amount of DABCO, followed by Paal-Knorr cyclization with primary amines is described. 6 (C) For the first time, Khalafy and Rimaz7 have reported the synthesis of pyridazines via condensation of phenylglyoxal with β-keto esters in the presence of an excess amount of hydrazine hydrate in 70- 97% yield. (D) Disubstituted imidazoles were prepared by reacting phenylglyoxal with different aryl aldehydes in the presence of ammonium acetate. The compounds showed good anti-inflammatory activities in carrageenan-induced rat paw edema test with very low ulcerogenic activity. Fair number of compounds were found to have significant antimicrobial activity especially against fungal species. 8 (E) M. Ayaz et al.9 used phenylglyoxal in a Petasis reaction in order to synthesize quinoxalines, which exhibit a large variety of biological activities such as antibacterial, antimalarial, antifungal, and antithrombotic activity. (F) Phenylglyoxal was used in a simple, practical, and a very regioselective three-component one-step procedure with 6-aminopyrimidines and dimedone for the preparation of a novel pyrrolo[2,3- d]pyrimidine ring system, a common motif in several natural products and biologically active molecules. 10 (G) A Pictet-Spengler reaction for the synthesis of 1-substituted β- carboline has been developed. Products A and B were synthesized via a reaction between phenylglyoxal and L-tryptophan in 45% and 35% yield, respectively. 11 (H) Ishihara and co-workers have reported a CuX2-catalyzed enantioselective intramolecular Cannizzaro reaction of phenylglyoxal. They have also found that the use of phenylglyoxal provides a solution to the problem of low reactivity in the asymmetric intramolecular Cannizzaro reaction with alcohols. 12. © Georg Thieme Verlag Stuttgart . New York.