Acyl

It refers to the atomic group RCO- obtained by removing OH from the carboxyl group of carboxylic acid RCOOH (R is a hydrocarbon group). It is named by changing the suffix -ic acid or -oic acid of the carboxylic acid name to -yl or -oyl. For example, acetylCH ₃ CO-, propionyl C ₂ H ₅ CO-, stearoyl C ₁₇ H ₃₅ CO-, oxalyl-CO-CO-, malonyl-COCH ₂ CO-, benzoyl C ₆ H ₅ CO-, cinnamoyl C ₆ H ₅ CH=CHCO-.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

カルボン酸RCOOH(Rは炭化水素基)のカルボキシル基からOHを除いた原子団RCO-をいう．カルボン酸名の語尾-ic acidまたは-oic acidを，-ylまたは-oylにかえて命名される．たとえば，アセチルCH₃CO-，プロピオニルC₂H₅CO-，ステアロイルC₁₇H₃₅CO-，オキサリル-CO-CO-，マロニル-COCH₂CO-，ベンゾイルC₆H₅CO-，シンナモイルC₆H₅CH=CHCO-．

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