small molecules that bind to CTG trinucleotiderepeats in DNA. 1H-Pyrrolo[3,2-h]quinoline-8-amine (PQA) has a tricyclic aromatic system with unique non-linear hydrogen-bonding surface complementary to thymine. We have synthesized a series of PQA derivatives with different alkylamino linkers. These PQAs showed binding to pyrimidine bulge DNAs and CNG (N = T and C) repeats depending on the linker structure
我们描述了一种新的分子设计,合成以及与DNA中CTG三核苷酸重复序列结合的小分子的研究。1 H-吡咯并[3,2- h ]喹啉-8-胺(PQA)具有三环芳族体系,其独特的非线性氢键表面与胸腺嘧啶互补。我们合成了一系列具有不同烷基氨基接头的PQA衍生物。这些PQA显示与嘧啶凸出的DNA结合,并且CNG(N = T和C)重复序列取决于接头结构,而缺少吡咯环的喹啉衍生物显示出更低的结合亲和力。PQA是CTG和CCG重复结合的有用分子单元。
Rozhkova; Ogrel'; Grigor'ev, Russian Journal of Bioorganic Chemistry, 1996, vol. 22, # 11, p. 732 - 738
Dimeric 2-amino-1,8-naphthyridine selectively binds to a G-G mismatch with hi-h affinity (K-d = 53 nM). We have investigated a binding mechanism of naphthyridine dimer 2 to a G-G mismatch by spectroscopic studies, thermodynamic analysis, and structure-activity studies for the thermal stabilization of the mismatch. H-1 NMR spectra of a complex of 2 with 9-mer duplex d(CATCGGATG)(2) containing a G-G mismatch showed that all hydrogens in two naphthyridine rings of 2 were observed upfield compared to those C of 2 in a free state. The 2D-NOESY experiments showed that each naphthyridine of 2 binds to a guanine in the, G-G mismatch within the pi -stack. In CD spectra, a large conformational change of the G-G mismatch-containing duplex was observed upon complex formation with 2. Isothermal calorimetry titration of 2 binding to the G-G mismatch showed that the stoichiometry for the binding is about 1:1 and that the binding is enthalpy-controlled. It is clarified by structure-activity studies that show (i) the linker connecting two naphthyridine rings was essential for the stabilization of the G-G mismatch, (ii) the binding efficiency was very sensitive to the linker structure, and (iii) the binding of two naphthyridines to each one of two Gs in the G-G pi -dsmatch is essential for a strong stabilization. These results strongly supported the intercalation of both naphthyridine rings of 2 into DNA base pairs and the formation of a hydrogen bonded complex with the G-G mismatch.
A New Generation of SpecificTrypanosoma cruzi trans-Sialidase Inhibitors
作者:Sabrina Buchini、Alejandro Buschiazzo、Stephen G. Withers