In this minireview we describe our work on the improvement of the nucleobase analogs Favipiravir (T-705) und its non-fluorinated derivative T-1105 as influenza and SARS-CoV-2 active compounds. Both nucleobases were converted into nucleotides and then included in our nucleotide prodrugs technologies cycloSal-monophosphates, DiPPro-nucleoside diphosphates and TriPPPro-nucleoside triphosphates. Particularly the DiPPro-derivatives of T-1105-RDP proved to be very active against influenza viruses. T-1105-derivatives in general were found to be more antivirally active as compared to their T-705 counterpart. This may be due to the low chemical stability of all ribosylated derivatives of T-705. The ribosyltriphosphate derivative of T-1105 was studied for the potential to act as a inhibitor of the SARS-CoV-2 RdRp and was found to be an extremely potent compound causing lethal mutagenesis. The pronucleotide technologies, the chemical synthesis, the biophysical properties and the biological effects of the compounds will be addressed as well.

中文翻译：

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改善核碱基类似物 T-705/T-1105 作为潜在抗病毒药物的特性。

在这篇迷你评论中，我们描述了我们在改进核碱基类似物 Favipiravir (T-705) 及其非氟化衍生物 T-1105 作为流感和 SARS-CoV-2 活性化合物方面的工作。两种核碱基都被转化为核苷酸，然后包含在我们的核苷酸前药技术中 cycloSal-monophosphates、DiPPro-nucleoside diphosphates 和 TriPPPro-nucleoside triphosphates。特别是 T-1105-RDP 的 DiPPro 衍生物被证明对流感病毒非常有效。与对应的 T-705 相比，T-1105 衍生物通常被发现具有更强的抗病毒活性。这可能是由于 T-705 的所有核糖基化衍生物的化学稳定性较低。研究人员研究了 T-1105 的三磷酸核糖基衍生物作为 SARS-CoV-2 RdRp 抑制剂的潜力，并发现它是一种极强的化合物，可导致致死突变。还将讨论化合物的前核苷酸技术、化学合成、生物物理特性和生物效应。