Vitamin E acetate

Vitamin E acetate [58-95-7] serves primarily as an antioxidant and is closely associated with selenium. Vitamin E usually is present in... 

GC analyses of the pupal secretion of E. borealis have indicated the presence of vitamin E acetate and other tocopherol derivatives [49,50]. However, in tests with ants, these compounds proved to be essentially inactive, whereas the secretion itself was potently deterrent. To find and identify the active components in the pupal Epilachna borealis secretion, NMR spectroscopic studies on the fresh secretion were carried out. One and two-dimensional NMR experiments revealed that the tocopheryl acetates account for only a relatively small percentage of the beetles5 total secretion (20%), whereas the major components represented a group of previously undetected compounds. By analysis of the COSY, HSQC and HMBC spectra of the mixture, these components were shown to be esters and amides derived from three (co-l)-(2-hydroxyethylamino)alka-noic acids 44-46. HPLC analyses coupled to a mass spectrometric detector revealed that the secretion contain a highly diverse mixture of macrocyclic polyamines, the polyazamacrolides (PAMLs) 47-52 (Fig. 8). 

Note In recovery experiments, the spike levels were 150mg for vitamin C, 2-20mg for the other WSVs, 5.0mg of vitamin A acetate, 0.5mg of vitamin D2 and 25mg of vitamin E acetate. 

Vitamin E acetate (DL-a-tocopberyl acetate) [7695-91-2] M 472.8, m -27.5°, b 194-196°/0.01mm, 222-224°/0.3mm, d 0.958, n 1.4958. It is a viscous liquid which is purified by distn under high vacuum in an inert atm and stored in sealed ampoules in the dark. It is considerably more stable to light and air than the parent unacetylated vitamin. It is insoluble in H2O but freely soluble in organic solvents. All eight stereoisomers have been synthesised. The commercially pure d-a-tocopheryl acetate (2R,4 R,8 R) has b 18O-2OO°/O.7mm and +3.9° (c 5, EtOH). [Cohen et al. HCA 64 1158 1981]. 

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