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hello my name is tyler roche and we'll

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be talking today about the formation of

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ribonucleosides from ketose

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intermediates

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prebiotic chemists have long struggled

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to form nucleosides from the canonical

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nucleobases and ribose in addition early

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sugar-forming reactions such as the

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traditional foremost reaction create a

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variety of sugars instead of

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specifically forming ribose

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my research shows that ketosis can

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isomerize to react with non-canonical

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nuclear bases such as barbituric acid

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and form nucleosides first of all

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ribulose can do this to isomerize to

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ribose and arabinos to form pentose

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nucleosides and second of all fructose

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can do this isomerizing to glucose or

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mannose to form hexose nucleosides

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finally fructose can undergo retroaldol

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reactions to form pentoses which form

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pentonucleocides

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this work reveals a pathway from the

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simplest sugar precursors to hexoses and

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pentoses which can form nucleosides

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i'd like to thank my funding sources and