N,O-Bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester(BSA/NHS) as coupling agents for dipeptide synthesis

A method using N,O-bis（trimethylsilyl）acetamide/N-hydroxysuccinimide ester（BSA/NHS） as coupling agents for dipeptide synthesis is descried. The coupling reaction between N-hydroxysuccinimide（NHS）esters and amines could be performed under mild conditions with N,O-bis（trimethylsilyl）acetamide（BSA） as coupling reagent and no additional acid/base is required. All byproducts and excessive reactants are water soluble or hydrolysable and easy to eliminate through water-washing at the purification stage.Moreover, all the reactants are inexpensive and widely used in conventional drug production.

Highly luminescent europium and terbium complexes based on succinimide and N-hydroxysuccinimide

The preparation of two highly luminescent europium（Ill） and terbium（Ill） complexes with succinimide （SI） and N-hydroxysuccinimide （NHSI） were reported, which were further investigated through elemental chemical analysis, thermal analysis, FT-IR, powder X-ray diffraction, SEM and fluorescence spectroscopy. Data collected through these analysis revealed the formation of the Eu（III） and Th（III） complexes with the above mentioned ligands at a metal to ligand （M：L） molar ratio of 1：3. Interesting conclusions regarding the effi- cient sensitization through the coordination site of the lanthanide luminescent centers were retained from the photoluminescent spectra inves- tigation. Strong luminescence emission was observed in case of Eu（III）-SI and Tb（III）-NHSI complexes while the corresponding Eu（III）-NHSI and Tb（III）-SI complexes exhibited no photo luminescent properties. Newly obtained luminescent lanthanide complexes may be of particular interest for various applications in optoelectronics.

Simple Detection Method of Biogenic Amines in Decomposed Fish by Intramolecular Excimer Fluorescence

Biogenic amines are known to have various biological functions such as not only neurotransmitter and cell proliferation but also food poisoning. Bacterially-decomposed amines such as histamine, agmatine, putrescine, cadaverine, spermidine and spermine cause allergic symptoms. We developed simple method for measurement of polyamine as indicator of food decomposition with a fluorometer by using 4-(1-Pyrene)butyric acid N-hydroxysuccinimide ester (PSE). PSE reacts with primary and secondary amino moieties of polyamines and produces the intramolecular excimer fluorescence. Excimer fluorescence with broad peak at around 470 nm was clearly detected in linear type biogenic amines such as putrescine, cadaverine, spermidine and spermine at 10 mM. However neither histamine nor trimethylamine altered the fluorescence. Decomposed sardine and mackerel by improper storage showed stronger intensity than fresh ones. Comparing with OPA-method, PSE method was useful for screening biogenic amines present in food, esp. fish since the analysis was simple after one-step purification procedure. An inexpensive system which can rapidly detect biogenic amines from food is necessary in a medium and small-sized food business. The technique using excimer has potential to realize the high through-put screening system for evaluation of food freshness and is expected to bring the public interests such as food security and safety of consumer.

Engineering BiOBr_(x)I_(1-x)solid solutions with enhanced singlet oxygen production for photocatalytic benzylic C-H bond activation mediated by N-hydroxyl compounds

The aerobic,selective oxidation of hydrocarbons via C-H bond activation is still a challenge.This work shows the achievement of the room temperature visible light driven photocatalytic activation of benzylic C-H bonds with N-hydroxysuccinimide over BiOBr_(x)I_(1-x)(0≤x≤1)solid solutions,whose valance bands were engineered through varying the ratio of bromide to iodide.The optimal BiOBr0.85I0.15 catalyst exhibited over 98%conversion ratio of ethylbenzene,which was about 3.9 and 8.9 times that of pure BiOBr and BiOI,respectively.The excellent photocatalytic activity of BiOBr0.85I0.15 solid solution can be ascribed to the orbital hybridization of the valence band containing both Br 4p and I 5p orbitals,which could promote photo-induced charge carrier separation and improve the generation of singlet oxygen.This work shed some light on the rational design of photocatalysts for targeted organic transformation.