Estrutura e Composição de Triacilgliceróis

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Chapter 26 755 27. a. There are three triacylglycerols in which one of the fatty acid components is lauric acid and two are myristic acid. Myristic acid can be at C-1 and C-3 of glycerol, in which case the triacylglycerol does not have any chirality centers. If myristic acid is at C-1 and C-2 of compound. glycerol, C-2 is an asymmetric carbon, and consequently, two enantiomers are possible for the b. There are six triacylglycerols in which one of the fatty acid components is lauric acid, one is myristic acid, and one is palmitic acid. The three possible arrangements are shown below (with the fatty acid components abbreviated as L, M, and P). Since each has an asymmetric carbon, each can exist as a pair of enantiomers for a total of six triacylglycerols. *CH-O-P *CH-O-L 28. CH2-OH 3 CH-OH 2 R²CO⁻ 29. The structure at left has a molecular formula = C₉H₁₄O₆ and a molecular weight = 218. Subtracting 218 from the total molecular weight gives the molecular weight of the methylene (CH₂) groups in the triacylglycerol. 722 218 = 504 Dividing 504 by the molecular weight of a methylene group (14) will give the number of methylene groups. 504 = 36 14 Since there are 36 methylene groups, each fatty acid in the triacylglycerol has 12 methylene groups.