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10–15 ꢀC; Step 3: KOH, ethanol, water, reflux; overall yield
for three steps: 50% for 2-Et and 64% for 2-iPr].
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a Ac-His6-DPhe7-Arg8-Trp9-NH2 tetrapeptide template and
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14. Atc related non-coding amino acids used in our study
include the following: