Page 107 - General Biochemistry

2) Systematic (IUPAC) name:
Carbon atom numbering begins from the carboxylic end of the molecule

backbone. Double bonds are labelled with cis-/trans- notation or E-/Z-
notation, where appropriate. This notation is generally more verbose than
common nomenclature, but has the advantage of being more technically
clear and descriptive ex: linoleic acid

Figure 24 linoleic acid

cis,cis-9,12-Octadecadienoic acid

N.B: Most common fatty acids have trivial names in addition to their systematic
names
3) Δx (or delta-x) nomenclature
Each double bond is indicated by Δx, where the double bond begins at the xth
carbon–carbon bond, counting from carboxylic end of the molecule

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