Pentanoic anhydride

Draw the product formed when pentanoic anhydride [(CH3CH2CH2CH2CO)20] is treated with each reagent. With some reagents, no reaction occurs. 

Higher acids or anhydrides give on heating the (acylamino)pyr midines, which may be cyclized to 8-alkylpurines. Thus, 8-butyladenine (2) is formed upon reaction with pentanoic anhydride via cyclization of the intermediate 5-(pentanoylamino)pyrimidine-4,6-diamine. ... 

Ethanoic pentanoic anhydride (acetic valeric anhydride)... 

Draw the two starting materials that will produce 2-methylpro-panoic pentanoic anhydride when they react. 

To name acid chlorides (the same idea applies to other halides, but we will encounter these less frequently), we take the name of the acid and replace the suffix with -oyl chloride. So 15.4 is ethanol chloride (but it mostly goes by its common name of acetyl chloride), 15.5 is 3-butenoyl chloride, and 15.6 is benzoyl chloride. Anhydrides are also named for the acids from which they are derived thus, 15.7 is ethanoic anhydride (but commonly goes by acetic anhydride) and 15.8 is benzoic pentanoic anhydride. 

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