Synthesis of novel 1,3,4-oxadiazole derivatives as potential antimicrobial agents.

Some new 3-acetyl-5-(3-chloro-1-benzo[b]thiophen-2-yl)-2-substituted phenyl-2,3-dihydro-1,3,4-oxadiazoles and 2-(3-chloro-1-benzo[b]thiophen-2-yl)-5-substituted phenyl-1,3,4-oxadiazoles have been synthesized and evaluated for antimicrobial activity. Initially, 3-chloro-1-benzo[b]thiophene-2-carbonyl chloride (1) was prepared from cinnamic acid in the presence of chlorobenzene and thionyl chloride. This compound (1) was treated with hydrazine hydrate to afford 3-chloro-1-benzo[b]thiophene-2-carbohydrazine (2) which was further reacted with various aromatic aldehydes to yield hydrazones (3a-h).

Thiadiazole fused indolo[2,3-a]carbazole based oligomers and polymer.

Indolo[2,3-a]carbazole-based heteroacenes containing thiadiazole units were synthesized. Compounds showed a sandwich herringbone packing in solid state with improved stability. The change in photophysical and electrochemical properties upon incorporation of an acceptor moiety (benzothiadazole) in a fused ring system was studied.

Synthesis and evaluation of the biological activities of some 3-{[5-(6-methyl-4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidin-5-yl)-1,3,4-oxadiazol-2-yl]-imino}-1,3-dihydro-2H-indol-2-one derivatives.

Reaction of ethyl-6-methyl-2-oxo-4-aryl-1,2,3,4-tetrahydropyrimidin-5-carboxylates (1a-i) with hydrazine hydrate yielded 6-methyl-2-oxo-4-aryl-1,2,3,4-tetrahydropyrimidin-5-carbohydrazides (2a-i). These products, on reaction with cyanogen bromide, gave 5-(5-amino-1,3,4-oxadiazol-2-yl)-6-methyl-4-aryl-3,4-dihydropyrimidin-2 (1H)-ones (3a-i). The resultant aminooxadiazolylpyrimidinones were condensed with isatin to obtain various 3-{[5-(6-methyl-4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidin-5-yl)-1,3,4-oxadiazol-2-yl]-imino}-1,3-dihydro-2H-indol-2-ones (4a-i).

Light scattering and luminescence studies on self-aggregation behavior of amphiphilic copolymer micelles.

The self-aggregation behavior of three amphiphilic graft copolymers, oligo(9,9-dihexyl)fluorence-graft-poly(ethylene oxide) (OHF-g-PEO), with different architectures was studied by dynamic and static light scattering (DLS and SLS) in combination with fluorescence spectroscopy and transmission electron microscopy (TEM). The formation of self-assembled polymeric micelles was confirmed by SLS and TEM. DLS and SLS analyses showed that the architecture of graft copolymers has a dramatic effect on critical aggregation concentration (CAC), micelle size distribution, apparent aggregation number (Nagg app), and apparent molecular weight of polymer aggregates (Mw,agg app).

Prevalence of pyridoxine dependent seizures in south Indian children with early onset intractable epilepsy: A hospital based prospective study.

Objectives: Determine the prevalence of pyridoxine dependent seizures in children less than 16 years of age attending a teaching hospital in south India with early onset (before 3 years) intractable epilepsy of unknown aetiology, using the criteria proposed by Baxter.

Method: A cohort of 81 children, fulfilling the above criteria, was given 15 mg/kg/day of oral pyridoxine for 7 days. Non-responders were given a further 7-day trial of 30 mg/kg/day.

Vialetto-Van Laere syndrome in two sisters born to consanguineous parents.

Vialetto-Van Laere syndrome is a rare anterior horn cell disease affecting young persons. Bulbar palsy with deafness is the characteristic feature. Of the total 35 cases reported in the literature, only one case was from India.