Volume 2

Recent advances in organic chemistry / by Alfred W. Stewart.

  • Stewart, Alfred W. (Alfred Walter), 1880-1947.
Date:
1927
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Recent advances in organic chemistry / by Alfred W. Stewart. Source: Wellcome Collection.

    60/408 (page 40)
    CHO CH. OH I CH. OH Rhamnose. CH. OH I CH. OH ch3 The hydroxyl group which is unattached by methylation is obviously the one which has lost its hydrogen atom in order to form the cyclic chain of the oxide-ring ; and thus if the positions of the three methoxy-radicles can be ascertained, the point of attachment of the oxide-ring is also established. Now on oxidation with nitric acid, trimethyl-rhamnose yields Carabo-trimethoxy-glutaric acid, the space formula of which is : COOH H-C-OMe | H-C-OMe MeO-C-H COOH This result proves beyond doubt that the three methoxy-groups in trimethyl-rhamnose lie on three directly-connected carbon atoms. But this limits the possible formulae of trimethyl- rhamnose to the two which are shown below: -CH. OH H—C—OMe I 0 H—C—OMe MeO—C—H I -C—H CH—OH i 0 IT—C^ H—C—OMe IT—C—OMe MeO—C—H CH3 Trimethyl-rhamnose. ch3 Alternative formula.