A Remarkably High-Speed Solution-Phase Combinatorial Synthesis of 2-Substituted-Amino-4-Aryl Thiazoles in Polar Solvents in the Absence of a Catalyst under Ambient Conditions and Study of Their Antimicrobial Activities

Abstract

Remarkably high-speed synthesis of 2-substituted amino-4-aryl thiazoles in polar solvents with a minimum threshold polarity index of 4.8 was found to proceed to completion in just 30–40 sec. affording excellent yields of thiazoles under ambient temperature conditions without the use of any additional catalyst. The purification-free procedure afforded libraries based around a known pharmacophore, namely, substituted arylthiazoles and generated samples of high purity. In terms of combinatorial synthesis in a single solution phase, our protocol is significantly better than those hitherto reported and is amenable for HTS. The in vitro biological tests of some thiazoles showed good activity towards gram-positive bacteria, gram-negative bacteria and fungi comparable with the standard drugs, nitrofurantoin and griseofulvin, for their antibacterial and antifungal activities, respectively.

Synthetic Aspects and First-time Assessment of 2-amino-1,3-selenazoles Against Mycobacterium tuberculosis

“…In the present work, we report the formation of this core in some common solvents under catalyst-free condition at room temperature. It should be mentioned that we were inspired by a similar work published in 2011 by Srinivasan and co-workers regarding the synthesis of 2-aminothiazoles [24]. In their paper, authors established that thiazole formation is fast at room temperature when polar solvents are used.…”

Chemistry and pharmacological activities of Thiazoles –A Review Update

“…Dighe et al 10 have investigated 2-amino-4-arylthiazoles and studied their antibacterial properties and interesting point is that they possess (Figure 2) good activity than standard (Nitrofurantoin).…”

6-(2-Morpholinoethyl)-thiazolo[3,2-a]pyrimidin-5-one: A novel scaffold for the synthesis of potential PI3kα inhibitors

“…A general approach to synthesize the designed compounds 4-6 (a-c) is shown in Scheme 1. 2-Amino-4-arylthiazoles 2a-c were prepared utilizing either phenacyl chloride or bromide according to a reported procedure [19] which is considered to be an easy, rapid and purification-free procedure. Thiourea was allowed to react with phenacyl halide at room temperature for 2-3 min to yield the corresponding arylthiazole.…”

“…Yield: 95%; mp 146-148°C (lit. mp 146°C) [19]; IR (KBr, m, cm À1 ): 3436 (NAH), 1598, 1539, 1516 (C@N, C@C). 3a-c (10 mmol) and the appropriate amine (10 mmol) was heated at 90°C in dry DMF (15 mL) containing triethylamine (2 mL) for 18 h. The reaction mixture was cooled to 20°C and poured onto ice-water.…”