Polyhydric alcohols, oxidation selectivity

In contrast to the oxidation of acyclic polyhydric alcohols in benzene,508 treatment of 1,2-O-isopropylidene-a-D-glucofuranose with silver carbonate-on-Celite in boiling methanol led to selective oxidation of the primary hydroxyl group, with the formation of the al-duronic acid derivative in 68% yield.517... 

Isotope effects have also been observed in whole cells. Acetobacter suboxydans selectively oxidizes polyhydric alcohols having a specific pattern of hydroxyl groups. It oxidizes D-mannitol at C-2 and C-5. When D-mannitol-I-t, D-mannitol-2-t, and D-mannitol-3-t are oxidized to D-ffuctose, the unlabeled half of the molecule is oxidized the more rapidly. This result was attributed188 to a primary isotope-effect at C-3, and a secondary isotope-effect at C-2. 

Protein instability mechanisms have been reviewed by several investigators.3-13 Chemical reactions such as oxidation, deamidation, proteolysis, racemization, isomerization, disulfide exchange, photolysis, and others will give rise to chemical instability. It is critical that when this happens, the denaturation mechanisms must be identified in order to select appropriate stabilizing excipients. These chemical excipients may be in the form of amino acids, surfactants, polyhydric alcohols, antioxidants, phospholipids, chelating agents, and others. 

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