Sentence:  Pyruvate is known to <WSD>enolize</WSD> rapidly under the conditions employed by Oshima and Tamiya; in contrast, the a-keto analogs of a number of other amino acids <WSD>enolize</WSD> at much slower rates. 
Meaning of the word marked with <WSD> tags:  To become an enol or enolate, often through isomerization.