Synthesis and antibacterial activity of hydroxylated 2-arylbenzothiazole derivatives

Abstract

Synthesis of amidoalkylated phenols (3a, b):Ethyl or methyl chloroformate (2 mmol) was added dropwise to a magnetically stirred solution of benzothiazole (0.270 g, 2 mmol, 0.22 mL) in acetonitrile (10 mL), followed immediately by phenol (0.094 g, 1 mmol). The stirring was then continued at 20 o C for 80 h. After that, the solvent was evaporated under reduced pressure, the residue was dissolved in dichloromethane (40 mL) and washed twice with water. The organic layer was dried (Na 2 SO 4 ) and the crude mixture was dry-loaded onto silica gel. The products were isolated by column chromatography on silica gel with mixtures of petrol / diethyl ether as the eluent.Ethyl 2-(4-hydroxyphenyl)benzo [d]thiazole-3(2H)-carboxylate 3a: Obtained using ethyl chlorofomate (0.217 g, 2 mmol, 0.19 mL); Chromatographed on silica gel with petroleum/diethyl ether (4:1, increasing polarity to 2:1), Yield: 83%; M.p. 127 -128 o C;

Quercetin Hybrids—Synthesis, Spectral Characterization and Radical Scavenging Potential

“…In this regard, ethyl chloroformate performed better than methyl chloroformate for higher-yielding products. The mixture of regioisomers was observed (monitored by TLC) with the equimolar ratio of starting reagents according to our previously published study [28]. For the reactions with benzimidazole and 5,6-dimethylbenzimidazole, the presence of Et 3 N as a hydrochloric scavenger was required.…”

“…The current direction of our scientific group is developing an accessible approach to various heterocycles [26][27][28]. The aim of this study is to apply this method for obtaining new quercetin-benzazole hybrids and evaluate their radical scavenging potential.…”

Synthesis and structural characterization of palladium pincer complexes: Sustainable synthesis of benzothiazoles

“…Further, the Pd(II) alkoxide ion (2) undergoes β-hydride elimination to produce the corresponding aldehydes (3) and Pd(II) hydride intermediate (4). Later, the in situ generated aldehyde ( 3) is subsequently condensed with 2-aminothiophenol to form a cyclic aminal intermediate 2-phenyl-2,3-dihydrobenzo[d] thiazole derivative (5). The intermediate (5) further reacts with (4) to generate Pd(II) amino species (6).…”

Cross‐Dehydrogenative Coupling Reactions between Phenols and Hetarenes: Modern Trends in Cross‐Coupling Chemistry of Phenols

“…These can oxidise to produce oxidative cross‐coupling products in the presence of o ‐chloranil, which acts as an external oxidant (Scheme 27). [74] It should be noted that the oxidation of the σ H ‐adducts bearing the 2‐naphthol moiety formed a quinone methide‐type product, as opposed to the oxidative coupling product.…”