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Synthesis and Evaluation of Reducing Capacity and Calcium Channel Blocking Activity of Novel 3,5-Dipropargylcarbonyl-Substituted 1,4-Dihydropyridines*

Novel pyridinium salts based on 4-(3-pyridyl)-3,5-dipropargylcarbonyl-1,4-dihydropyridine were obtained by quaternization of pyridine moiety with different alkyl halides. The reducing capacity of the synthesized compounds was evaluated using the phosphomolybdenum complex method. The obtained results confirmed that all tested compounds possessed reducing capacity. Ca2+ channel antagonist and agonist activities of the compounds were additionaly assayed by changes in intracellular Ca2+ ion concentration in H9C2 and A7R5 cell lines. The obtained data confirmed that all synthesized 1,4-dihydropyridine derivatives have smooth muscle selective antagonist activities, and in the case of 4-phenyl derivative the activity was 4.7 times higher than that of amlodipine.

PV Effect of Fullerene/Poly(3-Hexylthiophene) Blend Sensitized By Phthalocyanine Having Infrared Absorption Ct Band

An attempt was made to extend the photosensitivity spectral range of fullerene/poly(3-hexylthiophene) blend to NIR region by adding extra electron donor — hydroxygallium phthalocyanine (GaOHPc) with a strong and wide intermolecular charge transfer (CT) band around 830 nm. Multilayer cells of ITO/PEDOT: PSS/6 GaOHPc/P3HT: C61(CO2Et)2 have been prepared by spin coating with vacuum evaporated Al or In top electrodes. Significant photosensitivity of the cells was in 370–900 nm spectral range. However charge carrier photogeneration efficiency was 3 times higher for illumination in P3HT absorption band as compared with the GaOHPc CT band at 830 nm. But when GaOHPc was mixed in the blend forming P3HT:C61(CO2Et)2:GaOHPc active layer its CT band shifted to infrared part at 875 nm. At the same time the charge carrier photogeneration efficiency for illumination in GaOHPc CT band increased significantly, exceeding its value for illumination in P3HT absorption band.