A series of 1,8-dihydro-1-aryl-8-alkyl pyrazolo(3,4-b)indoles 4a-j, 5a-j and 6a-j has been synthesized and tested for their anti-inflammatory and anticonvulsant activities. Formation of the pyrazoloindole derivatives was achieved by treating arylhydrazones of N-alkyl indole-3-carbox-aldehydes 1a-j, 2a-j and 3a-j with ten times their mass of polyphosphoric acid as a condensing agent. The newly s...

New mixed-substituent amino/carboxyphenylporphyrins for a dye-sensitized TiO2 solar cell were prepared using several synthetic routes. The reaction of 4-carbomethoxyand 4-acetamidobenzaldehydes with pyrrole in propionic acid under aerobic conditions afforded mixtures of mixed amide/ester substituted tetraphenylporphyrins which were separated using centrifugal chromatography then deprotected to ...

A new series of substituted 8-fluro-4H-pyrimido[2,1-b] [1,3]benzothiazole-4-ones () substituted 7-methyl-4H-isoxazolo[2,3-a]pyrimidin-4-ones, and substituted 2-methyl-5,6,7,8-tetrahydro-9H-isoxazolo[2,3-a]pyridopyrimidin-9-ones, compounds I-VII, have been prepared via condensation of beta-keto esters with 2-aminopyridine derivatives, in the presence of polyphosphoric acid. The same technique ha...

A series of 5-(2'-indolyl)thiazoles were synthesized and evaluated for their cytotoxicity against selected human cancer cell lines. The reaction of thioamides 3 with 3-tosyloxypentane-2,4-dione 4 led to in situ formation of 5-acetylthiazole 5 which upon treatment with arylhydrazines 6 in polyphosphoric acid resulted in the formation of 5-(2'-indolyl)thiazoles 2. Among the synthesized 5-(2'-indo...

The first general procedure for the synthesis of 5 to 7-membered 1-aryl-2-iminoazacycloalkanes is presented, by microwave-assisted ring closure of ω-arylaminonitriles promoted by polyphosphoric acid (PPA) esters. 1-Aryl-2-iminopyrrolidines were easily prepared from the acyclic precursors employing a chloroformic solution of ethyl polyphosphate (PPE). The use of trimethylsilyl polyphosphate (PPS...