Predict the structure of a fatty acid that is trans 18:2 ($\Delta$^9,11).

Question

Quizplus · Accepted Answer

The fatty acid is trans 18:2, which means it has 18 carbons with a double bond between the 2nd and 3rd carbons from the omega end, and both bonds are in the trans configuration. The shorthand notation F1F1F1S1F1F1F10S1U1P19,11S1S1P0 can be translated as follows:
- F1F1F1 = three methyl branches on carbon 1
- S1 = double bond between carbons 2 and 3 (delta symbol indicates the location of the double bond)
- F1F1F10 = ten methyl branches on carbon 4
- S1U1 = one unsaturation between carbons 5 and 6 (U symbol indicates one unsaturation)
- P19,11 = carboxylic acid group on carbon 18 (omega end)
- S1S1P0 = no additional substituents on the carbon chain

Based on this information, the structure of the fatty acid can be drawn as:

CH3    CH3    CH3
      |       |       |
    CH2=CH--CH2--CH2--CH2--CH2--CH2--CH2--CH2--CH2--CH2--CH3
                            |
                         CH2--CH2--COOH

This structure matches choice B.

Predict the Structure of a Fatty Acid That Is Trans Δ\DeltaΔ

Predict the Structure of a Fatty Acid That Is Trans $\Delta$