Abstract

The nucleobase modified fluorescent DNA and RNA analogs are synthesized by the conjugation of aromatic scaffolds through linkers, comprising mostly ethyne/ethene or fused ring residues at the pyrimidine/purine ring. These scaffolds are mainly derived from the benzenoid aromatic molecules comprising electron withdrawing/donating characters. However, non-benzenoid aromatic scaffolds such as tropolone and related derivatives are constituents of various troponoid natural products. The conjugation of nucleobases with a troponyl moiety is underutilized for the synthesis of fluorescent DNA analogs. This report describes the synthesis and photophysical studies of 2-aminotroponyl conjugated deoxyuridine nucleosides and their DNA analogs. 2-Aminotropone derivatives are conjugated at the C-5 position of uridine through an ethynyl linker/pyrrolyl ring fusion and their DNA analogs. Their photophysical studies reveal that aminotroponyl deoxyuridine analogs exhibit solvent-dependent fluorescence properties. Moreover, pyrrolyl ring-fused aminotroponyl DNA oligonucleotides enhance the fluorescence after formation of duplexation with complementary sequences of native DNA oligonucleotides. Hence, these modified nucleosides and DNA are promising fluorescent analogs which could be useful to design the sequence-specific DNA probes.

摘要

核碱基修饰的荧光 DNA 和 RNA 类似物是通过连接体结合芳香支架合成的，主要包含乙炔/乙烯或嘧啶/嘌呤环上的稠合环残基。这些支架主要来源于具有吸电子/供电子特性的苯类芳香族分子。然而，非苯类芳香支架如托酚酮和相关衍生物是各种托酚类天然产物的成分。nucleobases 与 troponyl 部分的共轭未被充分利用用于荧光 DNA 类似物的合成。本报告描述了 2-氨基托苯酰结合的脱氧尿苷核苷及其 DNA 类似物的合成和光物理研究。2-氨基托酮衍生物通过乙炔基接头/吡咯环融合及其 DNA 类似物在尿苷的 C-5 位置缀合。他们的光物理研究表明，氨基托苯酰脱氧尿苷类似物表现出溶剂依赖性荧光特性。此外，吡咯环融合的氨基托酰基 DNA 寡核苷酸在与天然 DNA 寡核苷酸的互补序列形成双链后增强荧光。因此，这些修饰的核苷和 DNA 是很有前途的荧光类似物，可用于设计序列特异性 DNA 探针。吡咯环融合的氨基托酰基 DNA 寡核苷酸在与天然 DNA 寡核苷酸的互补序列形成双链后增强荧光。因此，这些修饰的核苷和 DNA 是很有前途的荧光类似物，可用于设计序列特异性 DNA 探针。吡咯环融合的氨基托酰基 DNA 寡核苷酸在与天然 DNA 寡核苷酸的互补序列形成双链后增强荧光。因此，这些修饰的核苷和 DNA 是很有前途的荧光类似物，可用于设计序列特异性 DNA 探针。