Step Cyclization to Give Part Belt Oxygen-Functionalized Pillar[6,10]arenes.

Part belt oxygen-functionalized pillar[6,10]arenes are synthesized by step cyclization. An oxygen-substituted tetramer and hexamer have been prepared to construct the O3 pillar[6]arene via a hexamer cyclization reaction and the O6 pillar[10]arene through a [4 + 1+4 + 1] cyclization reaction. X-ray crystallographic studies reveal that both macrocycles have a large cavity and indicate that the part belt oxygen-functionalized pillar[6,10]arenes have both similar cyclic structures and certain differences in configuration compared to pillararene.

Highly Reversible "On-Off-On" Fluorescence Switch Governed by pH, Utilizing Bis(Benzimidazole) Derivatives with Varied Link Groups.

In this work, a series of dibenzimidazole derivatives 1-4, act as highly reversible colorimetric and fluorescent pH chemosensor, were designed and synthesized. Excellent reversible pH response of these sensors could be found by a specific pH change through obvious fluorescent color changes. The response is not affected by common cations (including Al, Cu, Ca, Cd, Co, Cr, Mg, Na, K, Ni, Pb and Zn) and anions (including F, Cl, Br, I, ClO, HPO, HSO, HCO and CHCOO).

Identification of genes regulated by Wnt/beta-catenin pathway and involved in apoptosis via microarray analysis.

Background: Wnt/beta-catenin pathway has critical roles in development and oncogenesis. Although significant progress has been made in understanding the downstream signaling cascade of this pathway, little is known regarding Wnt/beta-catenin pathway modification of the cellular apoptosis.

Methods: To identify potential genes regulated by Wnt/beta-catenin pathway and involved in apoptosis, we used a stably integrated, inducible RNA interference (RNAi) vector to specific inhibit the expression and the transcriptional activity of beta-catenin in HeLa cells.