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Abstract: A novel route for the efficient synthesis of a target psoralen moiety, 4,4′-dimethylxanthotoxol, has been developed, which need only four steps using cheap pyrogallol as a starting material. Subsequently, a range of new glycosylated psoralen derivatives were synthesized in good yields with simple procedures and mild reaction conditions. The experiment of biological activity shows that some of the glycosylated psoralen derivatives have antiproliferative activities against human cancer cell lines. A strong photo-induced antiproliferative effects were found under UVA. All of the glycosylated psoralen derivatives exhibited antioxidant activities against the oxidation of DNA induced by Cu2+/glutathione (GSH). Further experiment also demonstrates that the introduction of sugar moieties in some glycosylated psoralen derivatives can improve their antioxidant activities significantly. [Copyright &y& Elsevier]

Abstract: A series of tri-O-alkylated inherently chiral fluorescent calix[4]crowns in the cone conformations and a series of tetra-O-alkylated inherently chiral fluorescent calix[4]crowns in the partial cone conformations have been synthesized. By condensing with chiral auxiliary (S)-BINOL, the resulting diastereomers could be separated via preparative TLC. We found that the size of the crown moiety effected the separation of the diastereomers. Further, removal of the BINOL unit by hydrolysis furnished pairs of enantiomers with optical purity. Moreover, we found that a tetra-O-alkylated inherently chiral fluorescent calix[4]crown-6 in the partial cone conformation 6c showed considerable enantioselective recognition capability towards chiral leucinol. [Copyright &y& Elsevier]

Abstract: The synthesis, structure and ring-closing metathesis (RCM) reactions of polyether bridged biscalix[4]arenes 6 in the partial cone conformation with upper rim allyl substituents are reported. The RCM reaction modes depend on the length of polyether chain. Diethylene glycolic chain produced the dimer 7a and linear oligomer 7a′ with multi-cavities, whereas triethylene and tetraethylene glycolic chains allowed direct cyclization through intramolecular head-to-tail pattern to yield novel bridged biscalix[4]arenes 7b–c. [Copyright &y& Elsevier]

A family of novel calix[4]arene derivatives containing nucleoside bases were designed and synthesized. Coupling reaction between para mono- or bis-amino calix[4]arenes 5, 6 or 7 and thymin-1-ylacetic acid in the presence of DCC afforded mono- or bis-thymine-substituted calix[4]arenes 8, 9 or 10 in over 70% yield. Owing to the low solubility of adenine-N9-ylacetic acid in DMF and DMSO and the weak nucleophilicity of aminocalix[4]arene derivatives, alternatively, the substitution reaction of bromoacetylated aminocalix[4]arenes derivatives 11, 12, 13 with adenine in the presence of sodium hydride was carried out to synthesize mono- or bis-adenine-substituted calix[4]arenes. Two kinds of isomers 15 and 16 or 17 and 18 were obtained due to the non-regiospecific alkylation of adenine, and their structures have been confirmed by 13C NMR and 1H NMR spectra. [Copyright &y& Elsevier]