Isopropylideneascorbic acids

Isopropylideneascorbic acid (62) has recently been shown to reduce adrenochrome in a similar manner to ascorbic acid the main products are 28 and an isopropylidene derivative of 60, i.e. 63.1 0... 

The stability constants with ascorbic (31) and 5,6-0,0 -isopropylideneascorbic acids (32) have been estimated and are almost independent of the nature of the ligands,492 which are unidentate, the hydroxyl groups in the lactone ring being involved in the coordination. A vanadyl ascorbate has been synthesized, formulated [V0(C6H7060H)]-2H20.493... 

Evidence has been provided to support a Michael-type mechanism for the addition of LiAHTj to C(3) of L-2,3-di-0-benzyl-5,6-0-isopropylideneascorbic acid, which affords (45, 5/f)-5,6-0-isopropylidene-4-hydroxy-2-benzyloxyhex-2-enol. ... 

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