Synthesis o novel arylboronic acids and their analytical use as luminescent reagents

基于洛芬具有较强的荧光(FL)和化学发光(CL)的特性，合成了四种新的芳基硼酸，它们是洛芬及其类似物的衍生物。鉴于某些芳基硼酸对鲁米诺-过氧化氢-辣根过氧化物酶(HRP)CL反应有促进作用，我们首先对它们的促进剂进行了评价。在所考察的化合物中，4-[4，5-二(2-吡啶)-1H-咪唑-2-基]苯基硼酸(DPPA)是最有效的促进剂。DPPA对HRP的检出限为0.15 ng(约3.5fmol)，约为不加增强剂时的180倍。利用具有延长发光效果的DPPA，将化学发光体系应用于硝酸纤维素膜上HRP的照相检测。在优化了化学发光反应条件后，仅有0.1 ng的HRP可被照相检测到。将该方法成功地应用于抗人T细胞白血病病毒I型的免疫印迹实验，考察了芳基硼酸的FL、FL和CL特性，为研制二醇类化合物FL探针或FL/CL标记剂奠定了基础。4-(4，5-二苯基-1H-咪唑-2-基)苯基硼酸(DPA)比洛芬具有更强的FL，而其他衍生物的FL较弱。与洛芬相比，并不是所有的衍生物都有更强的化学发光。尽管目前已用TLC法研究了DPA与部分二元醇的反应，但其反应活性和光谱仍需进一步研究。

Four kinds of novel arylboronic acids, which are the derivatives of lophine and its analogues, were synthesized based on the fact that lophine shows strong fluorescence (FL) and chemiluminescence (CL).Since some arylboronic acids are known to enhance the luminol-hydrogen peroxide-horseradish peroxidase (HRP) CL reaction, we evaluated those as enhancers at first. Among the compounds examined, 4-[4,5-di(2-pyridyl)-1H-imidazol-2-yl]phenyl boronic acid (DPPA) was found to be the most potent enhancer. The detection limit of HRP with DPPA was 0.15 ng (ca. 3.5 fmol) which was ca. 180 times better than that in the absence of the enhancer. By using DPPA with the effect of prolonging the light emission, the CL system was applied to the photographic detection of HRP on a nitrocellulose membrane. After optimizing the CL reaction conditions, as little as 0.1 ng of HRP was photographically detectable. This method was successfully applied to the western blotting assay of anti-human T-cell leukemia virus type-I.Next, FL and CL characteristics of the arylboronic acids were examined as fundamental studies on developing FL probes or FL/CL labeling reagents for diol compounds. 4-(4,5-Diphenyl-1H-imidazol-2-yl )phenylboronic acid (DPA) showed a stronger FL than lophine whereas the other derivatives had weaker FL. Stronger CL was not observed for all derivatives, compared to that of lophine. Although the reaction of DPA with some diols was estimated by TLC so far, further investigation on the reactivity and spectral studies will be required.