Pentanoyl

Part of speech: noun

Definitions

1. The five-carbon acyl radical derived from pentanoic acid, found in many organic compounds and esters
2. A chemical group with the formula C4H9CO that is obtained by removing the hydroxyl from valeric acid
3. An acyl substituent containing five carbon atoms, formed from the parent acid by losing its hydroxyl group

Etymology: Pentanoyl is a chemistry term built from two parts: "pent-", from Greek "pente" meaning five, and "-anoyl", the systematic name ending for an acyl group derived from an alkane with five carbons. Pentane is the five-carbon alkane, and the "-oyl" ending, which chemists use for acyl groups (the group left when a hydroxyl is removed from a carboxylic acid), was adopted as part of the systematic naming of organic compounds. The word is therefore a technical coinage rather than a term with an old everyday history. Its meaning comes straight from its construction: a five-carbon acyl group, written CH3(CH2)3CO-, that attaches to other molecules when chemists build esters, amides, and related compounds.