Adenosine, from ribosenucleic acid

The purine nucleosides from ribosenucleic acid are adenosine and guanosine. Historically, guanosine was the first ribose nucleoside to be discovered, having been isolated from plant extracts by Schulze in 1885 and named vernine. In 1909 it was prepared from ribosenucleic acid by Levene and Jacobs, who also isolated adenosine from the same source. These two nucleosides are readily hydrolyzed by dilute mineral acid to give the respective bases and the same sugar. 

Inosinic and Adenylic Adds, Similarly, Levene and Harris found that the adenylic acid from ribosenucleic acid can be deaminated to an inosinic acid which undergoes hydrolysis at its own pH to give hypo-xanthine and 3-phosphoribose. On the other hand, Thannhauser had shown that ammoniacal hydrolysis of the adenylic acid gives adenosine and phosphoric acid. 

Synthetic 3-phospho-adenosine, identical with that from ribosenucleic acid, has been prepared by direct phosphorylation of adenosine with phosphorus oxychloride in the presence of barium hydroxide, but this method of synthesis affords no confirmation of the above formulation. 

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