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Furthermore , the goals of lead identification are being expanded accordingly to identify not only ' key ' compounds that fit with a single - target ' lock ' , but also ' master key ' compounds that favorably interact with multiple targets ( i . e . operate a set of desired locks to gain access to the expected clinical effects ) .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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