Mazaahir Kidwai

The first Au-nanoparticles catalyzed green synthesis of propargylamines via a three-component coupling reaction of aldehyde, alkyne and amine

Recyclable Au-nanoparticles provide an efficient, economic, novel route for multi component A3 coupling reaction of aldehyde, amine and alkyne. This method provides the wide range of substrate applicability. This protocol avoids the use of heavy metals, co-catalyst and gives the propargylamine in excellent yields.

Solventless synthesis of thiohydantoins over K2CO3

Potassium carbonate supported solventless synthesis of thiohydantoins under microwave irradiation is described. The use of K2CO3 not only eliminates the need for external base to neutralize HCl evolved but enables aqueous work up, thus rendering the reaction procedure free of organic solvents in both the reaction step and work-up, procedure.

Convenient Preparation of Pyrano Benzopyranes in Aqueous Media

Abstract The three‐component reaction of aldehyde, malononitrile, and 4‐hydroxy coumarin has been efficiently performed in aqueous K2CO3 using a simple, clean, environmentally benign, novel procedure employing microwave irradiation. The observed yields and enhancement in reaction rates can be attributed to the uniform heating effect of microwave. The microwave‐accelerated reaction technique not only eliminates the use of external base and organic solvents but also requires only water in both the reaction step and workup, thus rendering the whole procedure into a truly ecofriendly protocol.

Microwave assisted solid support synthesis of novel 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazepines as potent antimicrobial agents

An environmentally benign and economic synthesis of 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazepines is described from readily accessible substituted 2-mercapto-1-amino triazoles and substituted chalcones on basic alumina that are accelerated by exposure to microwaves. The reaction time has been brought down from hours to seconds with improved yield as compared to conventional heating. The method reported herein is devoid of the hazards of solution phase reactions. All the synthesised compounds were tested for their in vitro antibacterial and antifungal activity. Some compounds showed significant antimicrobial properties. The best activity was observed with compounds 3a, 3c, 4a and 4d.

Ring Closure Reactions of Chalcones Using Microwave Technology

Abstract The synthesis of heterocyclic compounds containing pyrimidine, pyrazoline, isoxazoline and cyclohexenone ring from chalcone derivatives containing anisole and 3′4′-methylenedioxy phenyl ring under ‘dry conditions’ using microwaves and by conventional methods are described.

Synthesis of some novel substituted quinolines as potent analgesic agents

Summary2-Chloroquinoline-3-carbaldehyde and 2-chloro-4-methylquinoline-3-carbaldehyde have been prepared from acetanilide and acetoacetanilidevia a Vilsmeier-Haack reaction. Upon reaction with phenyl hydrazine, hydroxylamine, urea, and thiourea in presence of acetic acid, these chloroaldehydes afforded the title compounds which exhibit a several times higher analgesic activity than noramidopyrine (NAP).Zusammenfassung2-Chlorchinolin-3-carbaldehyd und 2-Chlor-4-methylchinolin-3-carbaldehyd wurden, ausgehend von Acetanilid und Acetylacetanilid, über eineVilsmeier-Haack-Reaktion hergestellt. Reaktion dieser chlorsubstituierten Aldehyde mit Phenylhydrazin, Hydroxylamin, Harnstoff und Thioharnstoff ergab die Titelverbindungen, deren analgetische Aktivität jene von Noramidopyrin (NAP) um ein Mehrfaches übertrifft.

Magnetic nanoparticles catalyzed synthesis of diverse N -Heterocycles

A large library of diversified compounds (pyrano [2,3-d]pyrimidines, pyrido[2,3-d] pyrimidines and a variety of spirooxindoles) were synthesized through a very efficient, economical and environmentally benign process utilizing magnetic nanoparticles. Ease of recovery using an external magnetic field is an additional ecofriendly attribute of this catalytic system. Most of the compounds are new; therefore, could be further explored for their pharmaceutical application. Moreover, column chromatography and recrystallisation of the products is not required as the crude products are already highly pure and hence can be used for target oriented synthesis on a wide scale.

Cu Nanoparticles in PEG: A New Recyclable Catalytic System for N‐Arylation of Amines with Aryl Halides

A new protocol for the N‐arylation of aryl halides with anilines using Cu nanoparticles in polyethylene glycol (PEG) as an efficient and reusable catalytic system has been developed. The reaction did not require any cocatalyst. Various solvents were screened, and PEG400 provided the best results. The studies showed that the mechanism of catalytic action is dependent on the size of the nanoparticles. The Cu nanoparticles and PEG were recyclable and retained their activity. This newly developed protocol was also found to be suitable for the cross coupling of NH heterocycles with iodobenzene. The present methodology offers several advantages, such as excellent yields, short reaction times, and milder reaction conditions.

AN EFFICIENT SYNTHESIS OF BENZOPYRANOPYRIMIDINES USING INORGANIC SOLID SUPPORT

ABSTRACT 4-Hydroxycoumarin on reaction with aldehydes in the presence of urea/thiourea using solid inorganic support under microwave irradiation (MWI) afforded 4-substituted benzopyrano [4,3-d]- pyrimidine derivatives in a few seconds with improved yield as compared to conventional heating. This efficient, facile and ecofriendly technique avoids the use of excess solvent and toxic acids usually employed in the process.

Microwave Assisted Synthesis and Antibacterial Activity of New Quinolone Derivatives

Summary. A series of novel 6-fluoro-7-(5-alkyl-1,3,4-thiadiazol/oxadiazol-2-ylsulfanyl)-4-quinolone-3-carboxylic acids were synthesized using microwave irradiation. The compounds were tested for their in vitro antibacterial activity. All compounds containing the 1,3,4-thiadiazole/oxadiazole moiety at position 7 showed promising antibacterial activity.Zusammenfassung. Einige neue 6-Fluoro-7-(5-alkyl-1,3,4-thiadiazol/oxadiazol-2-sulfanyl)-4-chinolon-3-carbonsäuren wurden unter Bestrahlung mit Mikrowellen synthetisiert. Die Verbindungen wurden hinsichtlich ihrer antibakteriellen Aktivität in vitro untersucht. Sämtliche Verbindungen mit 7-ständigen 1,3,4-Thiadiazol/Oxadiazol-Einheiten zeigten vielversprechende Aktivität.