Synthesis and antibacterial activity of 2-amino chromenes arising cyanoiminocoumarins and β-naphthol

Abstract

Abstract:The synthesis of 2-amino chromene, reported in our previous paper, has been accomplished by the reaction of cyanoiminocoumarin and β-naphthol. The obtained compound was reacted with various electrophilic or nucleophilic reagents. All the new homologous 2-amino-4H-chromenes have been characterized on the basis of their spectral (IR, 1 H and 13 C NMR) data and microanalysis. Four compounds were evaluated in vitro for their preliminary antibacterial activities against five different pathogenic bacterial strains such as Bacillus thuringiensis, Escherichia coli, Staphylococcus aureus, klebsiella pneumonia and Salmonella Sp. Antibacterial activity of each compound was compared with standard drug, Penicillin.

Recent advancement in the synthesis of diverse spiro-indeno[1,2-b]quinoxalines: a review

“…71,72 Chromenes are important classes of heterocycles because of their core being incorporated in a large variety of natural products and biologically active compounds. 73,74 Raghunathan et al 75 have introduced a structurally unique sugar and chromene based dipolarophile hybrid, namely (4-oxo-2-glyco-4H-chromene-3-carboxylate) 71, and accomplished a 3 + 2 cycloaddition reaction with dipoles generated in situ by the reaction of indenoquinoxalinone 3 and a-amino acids such as sarcosine 16a, L-proline 16d, and pipecolinic acid 16f in the presence of base NaOMe to produce the corresponding glyco polycyclic spiroindenoquinoxalines 72-74, respectively. The dipolarophile was synthesized by the reaction of glyconitroalkene 69 with 4-hydroxycoumarin 70 in the presence of Et 3 N and methanol (Scheme 43).…”

3-(Tetrazol-5-yl)-2-imino-coumarins Derivatives: Synthesis, Characterization, and Evaluation on Tumor Cell Lines

“…In the first step (Scheme 1), the 3-cyano-2-iminocoumarins 3 were synthesized from an equimolecular mixture of various substituted 2-hydroxy benzaldehyde 1 (1a: 2-hydroxy-3-methoxybenzaldehyde, 1b: 4-diethylamino-2-hydroxybenzaldehyde, 1c: 2,4-dihydroxybenzaldehyde, 1d: 2-hydroxynaphthaldehyde, 1e: 2-hydroxybenzaldehyde, 1f: 2-hydroxy-4-methoxybnezaldehyde, 1g: 5-bromo-2-hydroxybenzaldehyde, 1h: 3-ethoxy-2-hydroxybenzaldehyde) and propanedinitrile 2 in ethanol with 0.5% of piperidine at room temperature. After a reaction time of 8 -9 hours and elimination of volatile compounds in vacuo, the 3-cyano-2-iminocoumarins 3 were prepared easily according to this classical protocol previously developed in our laboratory [18] [19] [20].…”

Amidoalkyl Naphthols as Important Bioactive Substances and Building Blocks: A Review on the Current Catalytic Mannich-Type Synthetic Approaches

“…Naphthalene compounds are known to exhibit diverse biological activities. They possess anti-inflammatory [11], antibacterial [12][13][14], cardiovascular [15], antiproliferative [16], and antiviral [17] properties. A pharmaceutically interesting class of substances is the 1-amidoalkyl-2-naphthols, which possess the important 1,3-aminooxygenated moiety in their molecular structures, as well as an amide linkage, along with a naphthalene ring (Figure 1).…”