A novel crown functionalized diacetylene monomer, N-(2,3,5,6,8,9,11,12octahydrobenzo[b][1,4,7,10,13] pentaoxacyclopentadecin-15-yl) pentacosa-10,12-diynamide (BCDA), was synthesized successfully. The copolymerized composite vesicles of BCDA and 10,12pentacosadiynoic acid (DA) with embedded receptor sites for metal ions have been prepared and characterized. Their response to the presence of metal cations in aqueous solution has been investigated by monitoring changes of color and UV-vis absorption. Upon addition of a series of alkali, alkaline earth and transition metal cations such as

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Herein, we report a novel model that combines supramolecular chemistry and the LB technique for the chirality regulation of the PDA films. The helical packing of PCDA molecules and the chiroptical properties of the resulting PDA LB films can be easily modulated by different azobenzene derivatives. Moreover, the effect of the photo-isomerization of azobenzene chromophores on the helical formation of PCDA assemblies is investigated in detail.

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The aim of this research was to evaluate insecticidal activities of the essential oil of Rhynchanthus beesianus rhizomes against adults of Liposcelis entomophila and Tribolium castaneum. Gas chromatography-mass spectrometry analyses revealed the presence of 44 compounds with β-eudesmol (19.1%), elemol (8.1%), α-terpineol (8.0%), methyl eugenol (6.5%), and caryophyllene (4.8%) being the major constituents. Bioactivity-directed chromatographic separation of the oil led to the isolation of four constituents, elemol, β-eudesmol, methyl eugenol, and α-terpineol. The essential oil exhibited fumigant toxicity against the adults of L. entomophila and T. castaneum with LC50 values of 0.57 and 4.96 mg/L air while the two isolates, methyl eugenol and α-terpineol possessed fumigant toxicity against the booklice (LC50 = 0.15 and 0.48 mg/L air, respectively) and the beetles (LC50 = 1.81 and 4.96 mg/L air, respectively). The oil also possessed contact toxicity against the booklice and the beetles with LD50 values of 121.56 μg/cm2 and 54.93 μg/adult, respectively, while the two isolates β-eudesmol and elemol showed contact toxicity against L. entomophila (LD50 = 99.21 and 35.19 μg/cm2, respectively) and T. castaneum (LD50 = 35.26 and 8.89 μg/adult, respectively). The results indicate that the oil of R. beesianus rhizomes and its isolates have potential as a source for natural insecticides.