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A survey of the literature reveals that the number of coumarin derivatives having heterocyclic moieties either as substituent groups or fused with parent coumarin nucleus possesses a variety of functions and are widely used in drugs and dyes. Because of this wide utility, the synthesis of coumarin has remained a subject of active interest. Looking at the importance of these heterocoumarins and with a view to exploring new methods of their synthesis, the present work was undertaken and  this synthesis deals with  various 2-aryl-pyrido [3,2-c] coumarins. The compounds have been synthesized by reacting Mannich bases of various 4-hydroxy coumarins with pyridinium salts of various aroyl methyl bromides in the presence of ammonium acetate and acetic acid. All the compounds synthesized have been characterized by analytical and spectral data. Keywords: Pyrido, Coumarins, Krohanke’s reaction.

PS-TBD Triggered General Protocol for the Synthesis of 4H-Chromene, Pyrano[4,3-b]pyran and Pyrano[3,2-c]chromene Derivatives of 1H-Pyrazole and Their Biological Activities. -The catalyst is used for at least five runs without significant loss of catalytic activity. Most of the synthesized compounds show better antimicrobial activities against gram positive bacteria but less activity against gram negative bacteria. Some of the compounds exhibit similar antifungal activity as standard drugs. Compounds (VIb) and (VIII) are shown to be most efficient antioxidants in the series. -(VALA, N. D.; JARDOSH, H. H.; PATEL*, M. P.; Chin. Chem. Lett. 27 (2016) 1, 168-172, http://dx.

A series of 8 derivatives of chromene 5a-h synthesized via one-pot cyclocondensation reaction of N-allyl quinolones, α/β naphthol and malononitrile. And 8 derivatives of pyrimidines 8a-h bearing N-allyl quinolone have been synthesized by N-allyl quinolones, ethylacetoacetate, thiourea/urea in the presence of zinc triflate as less toxic catalyst. This methodology allowed the high conversion of product at room temperature. Titled derivatives were elucidated by FT-IR, 1H NMR, 13C NMR, elemental analysis, and mass spectral data.