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We describe here a rapid process for the preparation of new 9-chloromethyl-12-aryl-10,12-dihydrobenzo[5,6]chromeno[2,3-d]pyrimidin-11-ones 5a-d and 10-chloromethyl-7-aryl-7,9-dihydrobenzo[7,8]chromeno[2,3-d]pyrimidin-8-ones 6a-d by two different methods utilizing microwave irradiation. This methodology provides better yields (72%–80%) and high purity of the title compounds.

Compound (IIIc) is found to exhibit strong antibacterial and moderate antifungal activities.

This new cyclization cascade reaction gives at first Ugi hydrazones, which can be easily converted to the corresponding pyrazoles via a formal [3 + 2]-cycloaddition.

Two simple protocols using Sc(OTf)3 as the catalyst are presented for the synthesis of the title-compounds via three component condensation of pyrazolopyrimidines, aldehydes, and isocyanides.

Title compounds (III) and (V) are formed in a one-pot procedure via Dimroth rearrangement of intermediates obtained primarily from the reaction of pyrazoles (I) with carbon disulfide and Lawesson reagent, respectively.

With a view to their potential biological activity novel fused heterocycles (VII) are synthesized.

Some novel triazolo[4,3‐a]triazines derivatives were synthesized by reaction of N‐cyanoimidates and N‐ethoxycarbonylimidates with 3‐alkyl‐5‐amino‐1‐phenyl‐1,2,4‐triazoles.

Differential scanning calorimetry (DSC), dielectric constant, ac conductivity and Raman spectroscopy measurements are used to study the phase transitions of K 2 (SO 4 )·Te(OH) 6 crystal between 300 and 550 K. Two phase transitions are observed: a ferroelectric to paraelectric phase transition at 480 K and a transition between a low-temperature ordered state and a superionic conductivity state at 490 K. Dielectric data in the region 20–0.2 10 6 Hz show a pronounced dispersion relaxation frequency which obeys the Arrhenius law and two dielectric peaks, respectively, at 480 and 490 K. Raman scattering data provide evidence for the several phase transitions observed.