Lavado Nieves, Ávalos Martín, Babiano Reyes, Cintas Pedro, Light Mark E, Jiménez José Luis, Palacios Juan C
Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain.
Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
Orig Life Evol Biosph. 2016 Mar;46(1):31-49. doi: 10.1007/s11084-015-9456-z. Epub 2015 Oct 1.
We revisit herein the formation and structure of dihydroxy dioxanes, which can be obtained from prebiotically available precursors and can be regarded as primeval sugar surrogates. Previous studies dealing with the heterogeneous composition of interstellar bodies point to the existence of significant amounts of small polyalcohols along with oxygen-containing oligomers. Even though such derivatives did not give rise to nucleosides and oligonucleotides, nor they were incorporated into subsequent metabolic routes, molecular chimeras based on sugar-like species could be opportunistic scaffolds in pre-evolutionary scenarios. We could figure out that pseudosugars, assembled by hemiacetalic bonds from available precursors in both interstellar and terrestrial scenarios, were presumably more abundant than thought. Moreover, these species share some key features with naturally-occurring sugar rings, such as anomeric preferences, coordinating ability, and the prevalent occurrence of racemic compounds.
我们在此重新审视二羟基二氧六环的形成与结构，其可由益生元前体获得，且可被视为原始糖类替代物。先前关于星际天体异质组成的研究表明，存在大量小分子多元醇以及含氧低聚物。尽管此类衍生物未产生核苷和寡核苷酸，也未纳入后续代谢途径，但基于类糖物种的分子嵌合体在进化前的场景中可能是机会性支架。我们可以推断，在星际和地球场景中由可用前体通过半缩醛键组装而成的假糖，可能比想象中更为丰富。此外，这些物种与天然存在的糖环具有一些关键特征，如异头物偏好、配位能力以及外消旋化合物的普遍存在。
