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A simple and an efficient synthetic protocol were adopted for the synthesis of novel αaminophosphonates derivatives containing pyrazine moiety such as diethyl phenyl (pyrazin-2-yl-amino) methylphosphonates (4a-l) through one-pot three component Kabachnik-Fields reaction. Pyrazino-2-amine (1), different substituted aldehydes and triethyl phosphite (3) were reacted in toluene under microwave irradiation without catalyst to obtain title compounds. The newly synthesized compounds were screened for their in vitro antibacterial activity (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, and Salmonella typhimurium) and antifungal activity (Candida albicans, Aspergillus niger).

A convenient and efficient one-pot reaction has been employed for the synthesis of new aaminophosphonates 4a-4l via Kabachnik-Fields reaction in 89-95 % yields. In the procedure developed, equimolar quantities of 2phenylquinazoline-4-amine 1, various aromatic aldehydes 2a-2l and triethyl phosphite 3 was carried out under solvent-free conditions using Alum (KAl (SO4)2.12H2O). The products were characterized by IR, 1 H and 13 C spectra and elemental analysis. All the synthesized compounds were screened for in vitro antibacterial activity (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, and Salmonella typhimurium) and antifungal activity (Candida albicans, Aspergillus niger).

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.

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.

The results of a solvo-controlled self-assembly process involving a novel non-ionic protoporphyrin IX functionalized with triethylene glycol (Proto-NTEG) chains is discussed. In relatively non-polar aprotic solvents (cyclohexane/CHCl3), the protoporphyrin forms stable, uniformly-sized multilamellar micro-vesicles of approximately 65 nm diameter, while in more polar protic solvent mixes (CHCl3/MeOH), the same protoporphyrin forms micellar aggregates with dimensions of approximately 6 nm. The solvo-control operates based on the differing properties of glycol units in cyclohexane and methanol leading to inverse self-assembled structures.

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

Two complementary routes were developed for preparing novel octaphosphonate porphyrins. The use of protected/deprotected phosphonate-substituted precursors in the rational synthesis gave an overall yield 16%. A more streamlined synthetic path gave 21% overall yield of the target molecule. Octaphosphonate porphyrin possesses promising properties in supramolecular aggregate formation with cyclam. Cofacial reversible self-assembly of a meso-substituted octaphosphonate porphyrin with cyclam yields micrometer-long nanowires with a height of about 1-1.5 nm. The resulting wires were characterized by UV/Vis absorption, emission and atomic force microscopy and transmission electron microscopy.

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).

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 synthesis and characterization of a highly fluorescent core-substituted naphthalene diimide sensor (varphi = 0.34) bearing a bis-sulfonamide group is described. The compound shows a unique selectivity and reactivity for the fluoride ion over other anions in CHCl(3) by a two-stage deprotonation process leading to a colorimetric response. In DMSO solution, the sensor is shown to be highly selective for fluoride (K(a) approximately 10(6) M(-1)) over other anions with more pronounced changes in absorption characteristics.

This paper reports the efficient core-substitution of halogenated naphthalene diimides utilizing the Suzuki cross-coupling reaction to install various aryl substituents at the 2,6 positions. The UV-visible spectra of these compounds show a clear absorbance red shift and an enhanced fluorescence output, making them potential candidates for solar-cell dyes and electroactive elements for supramolecular materials.