Abstract
Successful implementation of ultrasound irradiation for the rapid synthesis of a novel series of 3-[1-(4-substituted-5-(aryldiazenyl)thiazol-2-yl)hydrazono)ethyl]-2H-chromen-2-ones 5a–h, via reactions of 2-(1-(2-oxo-2H-chromen-3-yl)ethylidene) thiosemicarbazide (2) and the hydrazonoyl halides 3(4), was demonstrated. Also, a new series of 5-arylidene-2-(2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hydrazinyl)thiazol-4(5H)-ones 10a–d were synthesized from reaction of 2 with chloroacetic acid and different aldehydes. Moreover, reaction of 2-cyano-N'-(1-(2-oxo-2H-chromen-3-yl)ethylidene)-acetohydrazide (12) with substituted benzaldehydes gave the respective arylidene derivatives 13a–c under the conditions employed. The structures of the synthesized compounds were assigned based on elemental analyses and spectral data. Also, the cytototoxic activities of the thiazole derivative 5a was evaluated against HaCaT cells (human keratinocytes). It was found that compound 5a possess potent cytotoxic activity.
Highlights
The synthesis of coumarins and their derivatives has attracted considerable attention from organic and medicinal chemists for many years as a large number of natural and synthetic products contain this heterocyclic nucleus [1,2,3,4,5]
Increases in reaction rate and yields occur on application of ultrasound waves [12,13,14,15,16]. In view of these observations and in continuation of our previous work on the synthesis of heterocyclic systems for biological evaluation [17,18,19], we report a facile route to various thiazole derivatives incorporating coumarin moieties using the ultra-sound irradiation technique
Upon coupling the thiazole derivatives 8(9) with diazotized aniline, in presence of sodium acetate trihydrate, the azo derivatives 5a–h were obtained. The structures of the latter products were confirmed by the appearance of a N=N band in the IR spectra and the lack of signals due to the C-5 proton of the thiazole ring in their 1H-NMR spectra
Summary
The synthesis of coumarins and their derivatives has attracted considerable attention from organic and medicinal chemists for many years as a large number of natural and synthetic products contain this heterocyclic nucleus [1,2,3,4,5]. A number of natural and synthetic coumarin derivatives have been reported to exert notable antimicrobial [1,2], antifungal [3,4] and cytotoxic [5] activity. Increases in reaction rate and yields occur on application of ultrasound waves [12,13,14,15,16] In view of these observations and in continuation of our previous work on the synthesis of heterocyclic systems for biological evaluation [17,18,19], we report a facile route to various thiazole derivatives incorporating coumarin moieties using the ultra-sound irradiation technique. We have found that one of the synthesized compounds has shown high cytotoxic activity
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
