New dsDNA binding unnatural oligopeptides with pyrimidine selectivity
作者:Zhenyu Zhang、Patrick Chaltin、Arthur Van Aerschot、Jeff Lacey、Jef Rozenski、Roger Busson、Piet Herdewijn
DOI:10.1016/s0968-0896(02)00268-7
日期:2002.11
to redirect the interaction to mixed sequences. This way, newunnatural oligopeptide motifs and hybridmolecules have been developed endowed with different sequence selectivities. The results demonstrate that the unnaturalpeptide library approach combined with subsequent modification of selected amino acid positions, is very suited for the discovery of novel sequence-specific dsDNA binding ligands.
固相肽库筛选,然后延伸前导识别元件以使用溶液相筛选结合到dsDNA序列(IL6的NF结合位点),从而交付了新的DNA结合肽Ac-Arg-Ual-Sar-Chi-Chi- Tal-Arg-CONH2。在本研究中,使用溴化乙锭置换试验研究了不同氨基酸侧链对肽与dsDNA结合强度的贡献。基于这些结果,通过反卷积优化了前导结构。在取代Ual-Sar片段的七肽的两个位置评估了八个新的非天然氨基酸。在这两个位置分别使用([(3-氯苯基)甲基]氨基]乙酸(Cbg)和β-环己基-1-丙氨酸(Cha)观察到最强的dsDNA结合。与Ual-Sar序列相比,亲和力增加了10倍。通过将新开发的肽片段与具有柔性间隔基的an啶衍生物连接的杂合分子,进一步增强了dsDNA的结合。这导致对dsDNA靶标的亲和力在microM范围内(K(d)为2.1 x 10(-6)M)。带有新开发的寡肽基序的DNase I足迹表明存在明
Regio- and stereoselective synthesis of 1,4-dihydropyridines by way of an intramolecular interaction of a thiocarbonyl or carbonyl with a pyridinium nucleus
Chiral 1,4-dihydropyridines were prepared by the regio- and stereoselective addition of ketenesilylacetals and organometallic reagents to pyridinium salts. In the addition reaction, an intramolecular interaction between the thiocarbonyl or carbonyl with the pyridinium nucleus plays an important role in bringing about the selectivities. The absolute configuration of the newly produced stereogenic
Cation−π Interactions of a Thiocarbonyl Group and a Carbonyl Group with a Pyridinium Nucleus
作者:Shinji Yamada、Tomoko Misono、Seiji Tsuzuki
DOI:10.1021/ja0490119
日期:2004.8.1
Attractive interactions between a thiocarbonyl group and a pyridinium nucleus, and between a carbonyl group and a pyridinium nucleus have been proven by (1)H and (13)CNMRstudies, UV-vis spectral analyses, and X-ray crystallographic analyses of nicotinic amides 1 and 3, and pyridiniumsalts 2 and 4. Comparison of the Deltadelta values, which are the differences in the chemical shifts with reference