John W. Kozarich

A chemical synthesis of adenosine 5′-[γ-32P]triphosphate

Adenosine 5′-[γ-32P]triphosphate has been prepared from adenosine 5′-diphosphate by condensation of the phosphorimidazolidate of ADP with 32Pi. No purification of intermediates is required in this efficient synthesis, which is convenient for micro-scale conversions. This procedure permits the preparation of [γ-32P]ATP of high specific activity and should be applicable to the synthesis of many nucleoside triphosphates, including some which may not be accessible by enzymatic means.

In situ generation of diazomethane

A continuous method for the production of diazomethane comprising the steps of feeding: ```a diazomethane precursor, and ```a base into a reactor vessel where they react to generate diazomethane, and removing the resulting diazomethane as a gas.

Chemical modifications of transfer RNA species. Transfer RNA's terminating in 2′- and 3′-O-methyladenosine

Abstract The preparation of transfer RNAs terminating in 2′- and 3′- O -methyl-adenosine has been undertaken by a combination of chemical and enzymatic techniques to permit a determination of the mechanism of tRNA aminoacylation. Neither of the two synthetic tRNAs was aminoacylated substantially in the presence of aminoacyl-tRNA synthetases, consistent with the hypothesis that the aminoacyladenylate moiety exists in the form of a species with considerable orthoester character.

Demethylation of 7-methylguanosine with lithium 2-methylpropane-2-thiolate

7-Methylguanosine, a component of transfer ribonucleic acid, is demethylated to guanosine, its presumed biochemical precursor, by a powerful new nucleophilic reagent, lithium 2-methylpropane-2-thiolate in hexamethylphosphoramide.