Hypoxanthine formula

Therapeutic Function Cardiotonic Chemical Name 9-/3-D-ribofuranosylhypoxanthine Common Name Hypoxanthine riboside Structural Formula ... 

In the early attempts to identify the nitrogenous bases of desoxy-ribosenucleic acid, some confusion arose for two reasons. At first, the products obtained by hydrolysis of nucleoprotein were studied, and there was no assurance that any particular base came from the nucleic acid rather than from the protein. Then, when the nucleic acid itself became available, the hydrolytic agents at first employed were sufficiently drastic to cause some deamination of the amino-purines (with the production of some xanthine and hypoxanthine) and some demethylation of thymine to uracil. In 1874, Piccard isolated guanine (and h3T>oxanthine) from sperm nuclein. Kossel and Neumann discovered in the hydrolysate of thymus nucleic acid two new pyrimidine bases which they named thy-mine and cytosine but they assigned incorrect empirical formulas to them. In 1894, they correctly described thymine as CsHgOjNs, but cytosine was not purified and characterized till much later. " " Levene now analyzed a series of nucleic acids from a variety of sources and found " that they all contained guanine and adenine. By mild hydrolysis of thymus nucleic acid, Steudel obtained guanine and adenine as the sole purine bases and demonstrated that they occur in equi-molecular proportions. Levene and Mandel confirmed this result and showed that the two purine bases and the two pyrimidine bases (thymine and cytosine) all occur in thymus nucleic acid in equimolecular proportions. 

This new sugar had the formula C5Hio04- In other words, it possesses one atom of oxygen less than does a pentose. Analysis of its benzyl-phenylhydrazone, of its guanine and hypoxanthine nucleosides, and of its thymine and cytosine nucleosides, confirmed this composition. It therefore appeared probable that the sugar might be a desoxypentose. 

The in vitro semi-automated microdilution assay technique that measures the ability of the extracts to inhibit the incorporation of [G- H] hypoxanthine (Amersham International, Buckinghamshire, UK) into the malaria parasite was used. The extracts were tested in duplicate at ten concentrations in two-fold dilutions and the experiment was repeated twice for each extract. Computation of the concentration of drug causing 50% inhibition of [G- H] hypoxanthine uptake (IC50) was carried out by interpolation after logarithmic transformation of both concentration and counts per minute (cpm) values using the formula ... 

Hypoxanthine, Hyp 6-hydroxypurine, a widely distributed purine derivative in plants and animals (formula, see Inosine), M, 136.11, m.p. 150 C (d.). It is produced during aerobic Purine catabolism (see) by deamination of adenine compounds or by hydrolysis of inosine compounds. It is found as a rare base in certain transfer RNAs. 

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