An efficient domino reaction in ionic liquid Synthesis and biological ev.pdf

Bioorganic Medicinal Chemistry Letters 23 (2013) 1656–1661Contents lists available at SciVerse ScienceDirect Bioorganic Medicinal Chemistry Letters journal homepage: www.elsevier .com/ locate/bmclAn efficient domino reaction in ionic liquid: Synthesis and biological evaluation of some pyrano- and thiopyrano-fused heterocycles0960-894X/$ - see front matter  2013 Elsevier Ltd. All rights reserved. /10.1016/j.bmcl.2013.01.079 ? Corresponding author. Tel.: +91 2692 226858; fax: +91 2692 236475. E-mail addresses: njpchemdeptspu@yahoo.co.in, naroo26@ (N.J. Parmar). OO O Seselin O N SMeO Thiopyranoquinoline Figure 1. Biologically active thiopyranoquinolines and pyranocoumaNarsidas J. Parmar ?, Rikin A. Patel, Bhagyashri D. Parmar, Navin P. Talpada Department of Chemistry, Sardar Patel University, Vallabh Vidyanagar, Dist. Anand, 388120 Gujarat, India a r t i c l e i n f oArticle history: Received 18 October 2012 Revised 5 January 2013 Accepted 17 January 2013 Available online 29 January 2013 Keywords: Thiopyranoquinoline Pyranocoumarin Triethylammonium acetate Domino/Knoevenagel-hetero-Diels–Alder Ionic liquida b s t r a c t An improved domino/Knoevenagel-hetero-Diels–Alder reaction of two new aldehyde substrates; 7-ole- finoxy-coumarin-8-carbaldehyde and 2-alkensulfanyl-quinoline-3-carbaldehyde, with pyrazolones was studied in ionic liquid triethylammonium acetate (TEAA), affording a series of pyrazolopyran annu- lated-pyrano-fused coumarins, and thiopyrano-fused quinolones. Besides acting as catalyst, since no additional catalyst used, the ionic liquid TEAA also promised its easy recovery. In all new polyheterocy- cles, the cis-fusion of two pyranyl rings had been inferred from 2D NMR COSY and NOESY experiments. All are good antitubercular agents, as they are found active againstMycobacterium tuberculosis H37Rv, and antibacterial agents, as they are found active against three Gram-positive (Streptococcus pneumoniae, Clostridium tetani, Bacillus subtilis) and three Gra