compound 5-acetamidopentanoate KEGG:C03087 UPa:UPC03087 C7H13NO3 CHEBI:2024 InChI=1S/C7H13NO3/c1-6(9)8-5-3-2-4-7(10)11/h2-5H2,1H3,(H,8,9)(H,10,11) compound