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A simple and straightforward protocol has been accomplished for synthesis of pyrazolo[3,4-b]pyridines by reacting 5-amino-1-phenyl-3-(trifluoromethyl)-1H-pyrazole-4-carbaldehyde (1) and β-enaminoketones (2) promoted by Iron(III)chloride. This protocol was also able to produce quinolines (5) by the reaction of O-nitrobenzaldehydes and β-enaminoketones. Simple reaction conditions, high compatibility and excellent yields are the advantages of this protocol.

A simple, highly efficient and selective oxidative cross coupling of imidazo[1,2-a]pyridine (IP) compounds (1) and methylketones (2), promoted by molecular iodine in DMSO in the presence of a catalytic amount of PTSA has been realized in a one pot reaction. This strategy has provided a general route for the synthesis of 1-aryl-2-(2-phenylimidazo[1,2-a]pyridin-3-yl)ethane-1,2-diones (3) with a new C–C bond formation through Kornblum oxidation followed by nucleophilic attack of IP compounds (1) on the in situ formed phenylglyoxal. Simple reaction conditions, no metal catalysts and selective product formation are the advantages of this protocol.

A one-pot access to cyclic 1,3-dione fused symmetrical 2,8-dioxabicyclo[3.3.1]nonanes (4) via acetic acid-mediated reaction of β-enamino ketones (1) and 1,3-cyclohexanediones (2) by heating under reflux is reported. The reaction proceeds via intramolecular cyclization of intermediate 2,2′-(3-oxo-3-arylpropane-1,1-diyl)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-one) (3) and is highly selective towards the formation of product 4. Unlike similar reactions, the presence of trifluoroacetic acid in a toluene medium affords xanthenes (5) exclusively.

A simple and efficient one pot protocol is accomplished to access tricyclic spiro dihydrofurans (4) by the reaction of β-enamino ketones (1) and dimedone (2) in ethanol followed by sequential addition of N-chloro succinimide (NCS) at ambient temperature for the first time. The Selectivity in desired product formation in good yields is the advantage of this protocol.

Synthesis of a series of novel aryl and heteroaryl fused 2,8-dioxabicyclo[3.3.1]nonanes (3) was accomplished by one pot, catalyst free reaction of 2-hydroxy chalcone (1) with 3-trifluoromethyl substituted pyrazolone (2) in xylene at reflux temperature. The role of the trifluoromethyl functional group in formation of 3 was confirmed by comparative studies with 3-methyl substituted pyrazolones (2c,d) and the outcome is presented.

We performed a structure-activity relationship (SAR) study of a novel aspirin (ASA) derivative, which shows strong anticancer activity in vitro and in vivo. A series of ASA-based benzyl esters (ABEs) were synthesized and their inhibitory activity against human colon (HT-29 and SW480) and pancreatic (BxPC-3 and MIA PaCa-2) cancer cell lines was evaluated. The ABEs that we studied largely comprise organic benzyl esters bearing an ASA or acyloxy group (X) at the meta or para position of the benzyl ring and one of four different leaving groups. The nature of the salicyloyl/acyloxy function, the leaving group, and the additional substituents affecting the electron density of the benzyl ring, all were influential determinants of the inhibitory activity on cancer cell growth for each ABE. Positional isomerism also played a significant role in this effect. The mechanism of action of these compounds appears consistent with the notion that they generate either a quinone methide or an m-oxybenzyl zwitterion (or an m-hydroxybenzyl cation), which then reacts with a nucleophile, mediating their biological effect. Our SAR study provides an insight into the biological properties of this novel class of compounds and underscores their potential as anticancer agents.

A mild and efficient method for the functionalization of chromen-2-ones with amidoalkyl derivatives have been developed starting from 4-trifluoromethyl substituted chromen-2-ones, aromatic aldehydes and acetamide promoted by stannous chloride dihydrate in a one pot three component reaction under solvent free condition. Simple reaction conditions, high yields and environmentally benign procedure are the advantage of this protocol.