27207
The challenge of locating two d - and one l - valine residue in 1 and 2 was accomplished by total synthesis using solid - phase peptide synthetic methods .
 Chemical: d - and one l - valine
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: d - and one l - valine