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Protoporphyrin IX species bearing highly branched alkyl chains were self-assembled into well-defined nanostructures such as rod-like in CHCl3–cylcohexane (1:9, v/v) and a honeycomb-like morphology in a polar solvent dimethyl sulfoxide (DMSO). The rod-like morphologies observed in the atomic force microscopy (AFM) and transmission electron microscopy (TEM) suggest that the lamellar phase self-organises into multilamellar vesicles. The X-ray diffraction (XRD) results indicate molecular arrangements resulting from longitudinal and transverse stacking of the porphyrin head groups in the lamellar structure. The typical nanostructures were derived from a high level of cooperativity between the porphyrin cores via π–σ interactions and supported by hydrogen bonding and van der Waals interactions. The nanostructures were characterised by means of UV–vis, fluorescence, AFM, TEM and XRD analysis. Our methodology confirms the potential of protoporphyrin IX derivatives in supramolecular chemistry.

Eaton's reagent efficiently catalyzed the Claisen-Schmidt condensation reaction of aryl aldehydes with aromatic and cyclic ketones under solvent free microwave irradiation conditions to afford mono and bis-chalcone derivatives. The present approach offers several advantages such as shorter reaction times, cleaner reactions, good yields, inexpensive reagent and mild reaction conditions

We have synthesized a novel derivative of kanamycin A bearing a pyrenyl fluorophore which can be used for the specific recognition of heparin in EtOH:H2O (1:3) through formation of a 2:1 complex. The receptor shows specific optical signalling for heparin, but exhibits no significant changes on addition of various other biological molecules.

In this study, we present a highly selective and sensitive technique for the detection of DNA using kanamycin A-functionalized AuNPs and ethidium bromide (a dye that binds specifically to DNA). Here, we demonstrate the interaction of the kanamycin A-modified-citrate gold nano particles with the DNA. Also, the interaction of the ethidium bromide-DNA complex with the kanamycin A-modified AuNPs is shown. Florescence is detected whenever the EtBr-DNA complex interacts with the kanamycin A-modified AuNPs. The transmission electron microscopic studies were also done to show the aggregation of the modified AuNPs in presence of the DNA. This further indicates that the binding of the kanamycin A modified gold particles to the DNA. This assay can be applicable in large scale characterization of DNA interactions and may also become the choice to complement conventional techniques in the non viral gene delivery system.

A simple, efficient and ecofriendly one pot synthesis protocol has been developed for the synthesis of N-substituted decahydroacridine-1,8-diones by using an efficient and recyclable solid acidic silica supported MoO3/SiO2 catalyst from a condensation of aldehyde, amine and cyclic 1,3-diketone in THF. The reaction using MoO3/SiO2 catalyst was carried out under mild condition with very high yields up to 92%. The present approach of this methodology offers several advantages such as shorter reaction times, good yields, low cost, environmentally benign, milder reaction conditions, easy recovery of catalyst and reusability.

Pyrazoles are important nitrogen containing 5-membered heterocyclic compounds. Numerous pyrazoline derivatives have been found to possess considerable biological activities, which stimulated the research activity in this field. Several 1,3,5-Triphenyl-1H-pyrazole containing 6-aminopyridazin-3(2H)-one derivatives has been synthesized. These new compounds were characterized using IR, 1H-NMR and Mass spectra and Elemental analysis. They possess some potent biological activities. Therefore biological screening of novel compounds has been also done.

We demonstrate new method for the synthesis of gold and silver nanoparticles from pineapple extract. Fur- thermore, we have studied interactions between nanoparticles (gold and silver) with aminoglycosides such as Kanamycin A, Neomycin. Both nanoparticles were prepared by reducing AuCl4 and AgNO3 using pineapple extract, kanamycin A and neomycin as both reducing and stabilizing agents respectively. Our new approach shows a clean method of synthesizing gold and silver nanoparticles that exhibit promising morphologies and stability under physiological conditions for several months in powder or aqueous form. Transmission electron microscopy (TEM) was employed to visualize the diameters of nanoparticles.

The self-assembly of a simple tetraalkyl-substituted protoporphyrin derivative into fibril wire-like nanostructures from CHCl3/cyclohexane solvent mixes is explored. The protoporphyrin IX derivative is synthesised in two efficient steps by amidation of the two propylenic acid groups followed by a cross metathesis of the vinyl groups using Grubbs' second-generation catalyst. The self-assembly of the functionalised protoporphyrin is sensitive to solvent and under favourable conditions forms ‘nanowires’ of micrometre length. The nanowires were characterised by absorption and fluorescence spectroscopy, transmission electron microscopy and atomic force microscopy.

A protoporphyrin IX amphiphile bearing hydrophobic–hydrophilic functional regions was synthesised by coupling protoporphyrin IX with methoxytriethylene glycol using (3-(dimethylamino)propyl)ethyl carbodiimide hydrochloride/1-hydroxybenzotriazole followed by a double-cross metathesis with 1-undecene using second-generation Grubb's catalyst. The self-assembling behaviour of the amphiphile in varying concentration of CHCl3/MeOH was investigated, with well-defined nanostructures described as worm-like fibrils and particular aggregates being formed in 1:1 and 1:9 v/v of MeOH/CHCl3, respectively.

A simple one-pot synthesis has been developed for the synthesis of 2,4,5-trisubstituted imidazoles using an efficient and recyclable MoO3/SiO2 solid acid catalyst by condensation of benzil or benzoin, benzaldehyde, and ammonium acetate in acetonitrile as a solvent. Using this solid catalyst, the reactions could be carried out under mild reaction conditions with very good yield of imidazoles, up to 95%. This catalyst could be recycled very easily, which makes this methodology environmentally benign.

2-Arylbenzothiazoles formed in good yields (65–90%) by the condensation of aminothiophenols with aromatic aldehydes using P2O5 at ambient temperature.

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

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

2-Arylbenzothiazoles formed in good yields (65–90%) by the condensation of aminothiophenols with aromatic aldehydes using P2O5 at ambient temperature.

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).

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).

The self-assembly of spherical silver nanoparticles with variable size and controlled organization using triglycine as an organic template is described. Triglycine and silver nitrate were used as the starting materials for the preparation of the spherical nanoparticles, and in the presence of copper cations, the particles further self-assembled into one dimensional nanostructures. The formation of supramolecular nanoaggregates was evaluated by means of UV/vis, TEM, SEM, and energy dispersive X-ray spectroscopy.