Development of Fluorescent Reagents for Chirality Recognition Based on π-Electron Interaction

分子识别的目标客体是在寡肽链末端含有Py基团的氨基酸试剂的研制。分子设计如下：在1，4-二氨基丁烷上以酰胺键的方式引入L-苯丙氨酸或相关分子。对于这种化合物，还引入了萘或芘的部分。该试剂有望通过氢键与客体分子形成络合物，并在络合物形成过程中观察到荧光变化，而与L或D-苯丙氨酸酯形成络合物时，荧光变化不大，而~1H核磁共振谱显示了对L或D-苯丙氨酸酯的手性识别。环糊精基试剂的研制选择环糊精作为分子识别基团，在环糊精的亚甲基上引入几个碳原子，该试剂的荧光强度随水溶液的pH变化而变化，可用作pH传感器。该试剂与客体分子如(-)冰片或1-金刚烷醇形成络合物时也有荧光变化。该试剂被客体分子诱导产生圆二色谱，对手性识别具有一定的应用价值。

Development of the reagent with pyrene moieties in the terminal of oligopeptide chain Amino acid[ was selected as a target guest of molecular recognition. A molecular design was carried out as follows: L-Phenylalanine or related molecules were introduced on 1,4-diaminobutane by amide bond. To this compound, naphthalene or pyrene moieties were also introduced. This reagent was expected to form a complex with guest molecule by the hydrogen bonds, and to show a fluorescence change was observed at the complex formation.However, a little fluorescence change was observed at the complex formation with L- or D- phenylalanine esters.On the other hand, the ^1H NMR spectra showed the chirality recognition for L- or D- phenylalanine esters.2. Development of cyclodextrin base reagentsCyclodextrin was selected as a molecular recognizing moiety, and naphthalene group was introduced on the cyclodextrin via methylene chain with several carbon atoms.This compound (reagent) exhibits a change of fluorescence intensity depending on pH off the aqueous solution, and can be used for a pH sensor.This reagent also shows a fluorescence change at the complex formation with guest molecules such as (-)borneol or 1-adamentanol. Induced circular Dichroism of this reagent by the guest molecules shows the usefulness for the chirality recognition.