Single crystal structure of a mixed-chain triacylglycerol: 1,2-dipalmitoyl-3-acetyl-sn-glycerol.
The mixed chain triacylglycerol 1,2-dipalmitoyl-3-acetyl-sn-glycerol was synthesized and its crystal structure was determined to a final reliability factor (R) of 0.11. Two molecules are present in the monoclinic unit cell: space group P2(1); a = 5.375(1), b = 8.286(2), c = 42.96(1) A; beta = 93.30(2) degrees, V = 1910 A3, rho = 1.065 g/cm3, and mu = 5.7 cm-1. The structure is a trilayer: a bilayer of palmitate chains packed in the beta mode (T parallel) and an interdigitated monolayer of acetates. The glycerol backbone and acetate extend roughly linearly from the sn-1 chain. The sn-2 chain bends around the C-2 carbon to lie next to the sn-1 chain. Analysis of the torsion angles indicate that the glycerol conformation of 1,2-dipalmitoyl-3-acetyl-sn-glycerol is markedly different from single acid triacylglycerols and from 1,2-diacyl-sn-glycerols but very similar to 1,2-dimyristoyl-sn-glycero-3-phosphocholine.
Goto
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M
National Chemical Laboratory for Industry, Kagaku Gijutsu Kenkyusho (Tsukuba Research Center), Ibaraki, Japan.
Kodali
D R
DR
Small
D M
DM
Honda
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K
Kozawa
K
K
Uchida
T
T
D003461:Crystallography; D008958:Models, Molecular; D008968:Molecular Conformation; D014280:Triglycerides
D014280:Triglycerides; C076499:1,2-dipalmitoyl-3-acetyl-sn-glycerol