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Aim: Synthesis of some novel formazan derivatives from condensation of aniline diazo-nium salt with a variety of Schiff bases of 3,4-dimethyl-1H-pyrrole-2-carbohydrazidemoiety and evaluate their potential antimicrobial and antioxidant activities.Methods: Novel substituted formazans (2a-j) were prepared from Schiff bases of 3,4-dimethyl-1H-pyrrole-2-carbohydrazide (1a-j) by condensation with aniline diazoniumchloride in pyridine (Scheme 1). All the formazan derivatives were characterized by IR, 1 HNMR, 13 C NMR and Mass spectroscopy.Results: These molecules (2a-j) exhibits moderate to good antimicrobial and antioxidantactivities some of which are comparable to standards used in this study.Conclusion: The results of preliminary bioassays of derivatisation of Schiff bases to for-mazan indicate that a number of these molecules exhibits moderate to good antibacterial,antifungal and antioxidant activities some of which are comparable to standard used inthis study. The outcome indicates that there is a good scope for evaluation of this class ofcompounds as potential leads towards antimicrobial and antioxidant agents.Copyright a 2013, JPR Solutions; Published by Reed Elsevier India Pvt. Ltd. All rightsreserved.

We report a greener, economical, highly convenient and regioselective synthesis of (2E)-2-[2,3,6-arylpyrimidin-4(3H)-ylidene)acetonitriles derivatives 3. This is achieved by a strategy involving ring transformation reaction of 4-(methylthio)-2-oxo-6-aryl-2H-pyran-3-carbonitrile 1 with N-arylbenzamidine or N-arylpicolinamidine 2 in the presence of KOH/DMF catalyst at room temperature. This approach provides a one-pot approach for the synthesis of symmetrical, unsymmetrical and heteroaryl pyrimidin-4(3H)-ylidene)acetonitriles derivatives 3. Figure options Download full-size image Download as PowerPoint slide

The reaction in polyethylene glycol in the absence of any catalyst is a novel and eco-friendly method for the synthesis of pyridones.

Herein, we present an innovative, novel, and highly convenient protocol for the synthesis of 3-(pyridin-2-yl)-5-sec-aminobiphenyl-4-carbonitriles (6a, 6b, 6c, 6d, 6e, 6f, 6g) and 9,10-dihydro-3-(pyridine-2-yl)-1-sec-aminophenanthrene-2-carbonitriles (10a, 10b, 10c, 10d, 10e), which have been delineated from the reaction of 4-sec-amino-2-oxo-6-aryl-2H-pyran-3-carbonitrile (4a, 4b, 4c, 4d, 4e, 4f, 4g) and 4-sec-amino-2-oxo-5,6-dihydro-2H-benzo[h]chromene-3-carbonitriles (9a, 9b, 9c, 9d, 9e) with 2-acetylpyridine (5) through the ring transformation reaction by using KOH/DMF system at RT. The salient feature of this procedure is to provide a transition metal-free route for the synthesis of asymmetrical 1,3-teraryls like 3-(pyridin-2-yl)-5-sec-aminobiphenyl-4-carbonitriles (6a, 6b, 6c, 6d, 6e, 6f, 6g) and 9,10-dihydro-3-(pyridine-2-yl)-1-sec-aminophenanthrene-2-carbonitriles (10a, 10b, 10c, 10d, 10e). The novelty of the reaction lies in the creation of an aromatic ring from 2H-pyran-2-ones and 2H-benzo[h]chromene-3-carbonitriles via two-carbon insertion from 2-acetylpyridine (5) used as a source of carbanion.

We report a greener, economical, highly convenient and regioselective synthesis of (2E)-2-[2,3,6-arylpyrimidin-4(3H)-ylidene)acetonitriles derivatives 3. This is achieved by a strategy involving ring transformation reaction of 4-(methylthio)-2-oxo-6-aryl-2H-pyran-3-carbonitrile 1 with N-arylbenzamidine or N-arylpicolinamidine 2 in the presence of KOH/DMF catalyst at room temperature. This approach provides a one-pot approach for the synthesis of symmetrical, unsymmetrical and heteroaryl pyrimidin-4(3H)-ylidene)acetonitriles derivatives 3. Figure options Download full-size image Download as PowerPoint slide

The reaction in polyethylene glycol in the absence of any catalyst is a novel and eco-friendly method for the synthesis of pyridones.

The ring transformation of 2H-pyran-2-ones by N-aryl amidines is strongly influenced by the amidine substituents and leads to title compounds of type (III).