title: On the Plausibility of Pseudosugar Formation in Cometary Ices and Oxygen-rich Tholins.
abstract: 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.
authors.affiliation: Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain. nlavador@gmail.com.
authors.forename: Nieves
authors.identifier: http://orcid.org/0000-0002-5553-1541
authors.initials: N
authors.lastname: Lavado
authors.affiliation: Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain.
authors.forename: Martín
authors.initials: M
authors.lastname: Ávalos
authors.affiliation: Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain. reyes@unex.es.
authors.forename: Reyes
authors.initials: R
authors.lastname: Babiano
authors.affiliation: Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Cintas
authors.affiliation: Department of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Light
authors.affiliation: Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Jiménez
authors.affiliation: Departamento de Química Orgánica e Inorgánica, Facultad de Ciencias-UEX, Avenida de Elvas s/n, E-06006, Badajoz, Spain.
authors.forename: Juan C
authors.initials: JC
authors.lastname: Palacios
mesh_terms: D054329:Carbasugars / Q000737:chemistry*; D004146:Dioxanes / Q000737:chemistry*; D005118:Extraterrestrial Environment; D019110:Meteoroids; D010100:Oxygen; D016082:Solar System; D013237:Stereoisomerism
chemical_list: D054329:Carbasugars; D004146:Dioxanes; D010100:Oxygen
keywords: Comets; Prebiotic chemistry; Racemic compounds; Sugars; Tholins