https://doi.org/10.1351/goldbook.F02425
@F02423@ tightly bound or covalently attached to a protein chain, commonly through the 8-methyl carbon atom.
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1335 [Terms] [Paper]