diketopiperazine
noun
di·ke·to·pi·per·a·zine
| \ (ˌ)dī-ˌkēt-ō-pī-ˈper-ə-ˌzēn
\
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Medical Definition of diketopiperazine
1
: a compound C4H6N2O2 that is obtainable from two molecules of glycine by dehydration and may be regarded as a cyclic dipeptide
2
: any of various cyclic compounds formed similarly to diketopiperazine from alpha-amino acids other than glycine or obtained by partial hydrolysis of proteins