D. R. Patil

A novel and efficient one step synthesis of 2-amino-5-cyano-6-hydroxy-4-aryl pyrimidines and their anti-bacterial activity

The first simple and efficient approach towards one step synthesis of 2-amino-5-cyano-6-hydroxy-4-aryl pyrimidines has been developed by three component condensation of aromatic aldehydes, ethyl cyanoacetate and guanidine hydrochloride in alkaline ethanol. The synthesized compounds evaluated for their anti-bacterial activity against gram-positive and gram-negative bacteria. The some of the compounds showed excellent zone of inhibition against tested bacteria.

Contemporary development in sequential Knoevenagel, Michael addition multicomponent reaction for the synthesis of 4-Aryl-5-oxo-5H-indeno[1,2-b]pyridine-3-carbonitrile

An uncatalyzed efficient synthesis of bioactive pyridine derivatives has been investigated for the first time by a three-component sequential multicomponent reaction tackled with aromatic aldehydes, malononitrile, and 1,3-indandione via Knoevenagel condensation followed by Michael addition. The difference between the domino multicomponent and sequential multicomponent reaction is emphasized by this methodology. The reaction proceeds at ambient temperature without frequently useful N-source like ammonium salt for the construction of N-heterocycles, which makes this protocol a novel synthetic route for the preparation of the indenopyridine skeleton.Graphical Abstract

One Step Synthesis of 6-Amino-5-Cyano-4-Phenyl-2-Mercapto Pyrimidine Using Phosphorus Pentoxide

A simple and efficient approach towards one step synthesis of 6-amino-5-cyano-4-phenyl-2-mercapto pyrimidine and its hydroxyl derivatives have been developed by three component condensation of aromatic aldehydes, malononitrile and thiourea/urea in presence of phosphorus pentoxide (Scheme 1).

Protic ionic liquids: a lucid, rational tool for synthesis of phthalazinediones, quinoxalines and benzopyrans

Protic ionic liquids (PILs), which are easily produced through the combination of a Brønsted acid and Brønsted base, such as [Mim]Ac and 1,4-diazabicyclo[2.2.2]octane (DABCO):AcOH:H2O (1:1:3), were found to be lucid, tunable tool for synthesis of various heterocyclic motifs such as phthalazinediones, quinoxalines and benzopyrans. These PILs were found to be efficient for synthesis of diverse heterocyclic derivatives, along with demonstrating noteworthy aspects such as high yields, isolation of pure products without column chromatography and recyclable reaction media.Graphical abstract

Synthesis of some novel quinone diimine derivatives of benzo-15-crown-5 for application in Hg 2+ recognition

A series of novel fluoroionophore bearing derivatives of benzo-15-crown-5 were synthesized by the amination of benzo-15-crown-5 followed by condensation with different quinones in the presence of titanium tetrachloride (TiCl4 ) and 1,4-diazabicyclo-[2.2.2]octane. The compounds were characterized by infrared, (1) H and (13) C nuclear magnetic resonance, mass spectroscopy and elemental analysis. Absorption and fluorescence spectral characteristics of these compounds were studied. It was observed that the anthraquinone derivative was acting as an Hg(2+) ion sensor.

9-(3,4-Dimeth-oxy-phen-yl)-3,3,6,6-tetra-methyl-1,2,3,4,5,6,7,8,9,10-deca-hydro-acridine-1,8-dione.

The asymmetric unit of the title compound, C25H31NO4, contains two independent molecules. In one molecule, the benzene ring and an attached methoxy group were refined as disordered over two sets of sites in a 0.65 (4): 0.35 (4) ratio. In both molecules, the central ring of the acridinedione system adopts a flattened boat conformation. The four essentially planar atoms of this ring [maximum deviations = 0.006 (5) Å in both molecules] forms dihedral angles of 86.8 (2) and 87.6 (2)°, respectively, with the major and minor components in the disordered benzene ring and 87.3 (2)° with the benzene ring in the fully ordered molecule. The two outer rings of the acridinedione system adopt sofa conformations in both molecules. In the crystal, N—H⋯O hydrogen bonds form two independent chains along [100]. C—H⋯O hydrogen bonds link the chains, forming a three-dimensional network.

9-(3-Fluoro-phen-yl)-3,3,6,6-tetra-methyl-1,2,3,4,5,6,7,8,9,10-deca-hydro-acridine-1,8-dione.

In the title molecule, C23H26FNO2, the central ring of the acridinedione system adopts a slight boat conformation and the four essentially planar atoms of this ring [maximum deviation = 0.019 (1) Å] form a dihedral angle of 89.98 (6)° with the benzene ring. The two outer rings of the acridinedione system adopt sofa conformations. In the crystal, N—H⋯O hydrogen bonds link the molecules, forming chains along [001].

2-Amino-7,7-dimethyl-5-oxo-4-[3-(trifluoro-meth-yl)phen-yl]-5,6,7,8-tetra-hydro-4H-chromene-3-carbonitrile.

In the title molecule, C19H17F3N2O2, the fused cyclohexene and pyran rings adopt sofa and flattened boat conformations, respectively. The four essentially planar atoms of the pyran ring [maximum deviation = 0.008 (2) Å] form a dihedral angle of 88.13 (9)° with the benzene ring. The F atoms of the trifluoromethyl group were refined as disordered over three sets of sites in a 0.507 (7):0.330 (7):0.163 (3) ratio. In the crystal, molecules are connected into inversion dimers via pairs of N—H⋯N hydrogen bonds and these dimers are further linked by N—H⋯O hydrogen bonds into a two-dimensional network parallel to (100).

Synthesis and X-Ray Crystal Structure of Two Acridinedione Derivatives

The two acridinedione derivatives 1 [3,3,6,6-tetramethyl-9-(4-methoxyphenyl)-3,4,6,7,9,10-hexahydro-2H,5H-acridine-1,8-dione (C24H29NO3)] and 2 [3,3,6,6-tetramethyl-9-(4-methylphenyl)-3,4,6,7,9,10-hexa-hydro-2H,5H-acridine-1,8-dione (C24H29NO2)] were synthesized and their crystal structures were determined by direct methods. The asymmetric unit of compound 1 contains two independent molecules. The 1,4-dihydropyridine (DHP) ring adopts boat conformation in both 1 and 2. In 1 the dione rings exist in sofa conformation (for both the crystallographically independent molecules) while the corresponding rings in 2 adopt half chair and sofa conformations, respectively. The crystal packing is stabilized by intermolecular N–H⋯O and C–H⋯O interactions in compound 1 and N–H⋯O interactions in compound 2.

9-(4-Hy-droxy-3-meth-oxy-phen-yl)-3,3,6,6-tetra-methyl-1,2,3,4,5,6,7,8,9,10-deca-hydro-acridine-1,8-dione.

In the title molecule, C24H29NO4, the central ring of the acridinedione system adopts a flat boat conformation and the four essentially planar atoms of this ring [maximum deviation = 0.001 (2) Å] form a dihedral angle of 85.99 (12)° with the benzene ring. The two outer rings of the acridinedione system adopt sofa conformations. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the molecules, forming a two-dimensional network parallel to (100).