Synthesis of novel tetrakis(2,6-dimethyl-4-phenyl-1,4-dihydropyridinyl)methanes5a–dby acid-catalyzed condensation of the tetrakis-aldehydes6a–dwith eight equivalents of 3-aminobut-2-enenitrile2is reported. Antitumor activities of compounds5a–dwere also investigated.

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A simple, efficient, and eco‐friendly procedure has been developed for the synthesis of bis(4H‐chromene‐3‐carbonitrile) derivatives using chitosan as catalyst under microwave‐assisted reaction conditions. For the sake of comparison, the reaction was also carried out under conventional heating in the presence of each of chitosan and piperidine as basic catalysts.

Mirror symmetry breaking in systems composed of achiral molecules is of importance for the design of functional materials for technological applications as well as for the understanding of the mechanisms of spontaneous emergence of chirality. Herein, we report the design and molecular selfassembly of two series of rod-like achiral polycatenar molecules derived from a π-conjugated 5,5'-diphenyl-2,2'bithiophene core with a fork-like triple alkoxylated end and a variable single alkylthio chain at the other end. In both series of liquid crystalline materials, differing in the chain length at the trialkoxylated end, helical self-assembly of the π-con-* ] ). Further chain elongation results in removing the I23 phase and the re-appearance of the Ia � 3d phase with different pitch lengths. In the second series an additional tetragonal phase separates the two cubic phase types.

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