2-methyl-6phytylquinol and 2,3-dimethyl- Phytylquinol as Precursors of Tqcopherol Synthesis in Spinach Chloroplasts
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چکیده
The incorporation of [Me-‘“C] from SAM-[Me-r4C] into precursors indicates the following sequence of tocopherol synthesis in spinach: 2-methyl-6phytyIquinol (6-phytyltoluquinol) (la) ---, 2,3-dimethylphytylquinol (ph~ylpl~t~uinol) @n)--, y-tocopberol ($@+a-tocopherol (6). la is particularly preferred to 2methyl-5-phytyiquinol (lb) and Z-methyl-3-phytylquinol (1~). 1~ only forms 2a. 2~ is converted to 6 via ti and, to a lesser extent, 2,54methyl-6-phylquinol (2b) to 6 via f3-tocopherol (5b). Trimethylphytylquinol (3) is not an intermediate in the formation of 6. All reactions are independent of light.
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