ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Fast-atom-bombardment (FAB) mass spectra have been used to establish or confirm the nature of the yellow-product and open-chain forms of thiamine produced in the presence of excess (5 mol-equivb.) of strong base. Time-dependent changes in 1H-NMR spectra show that the rates of disappearance of the yellow form and of formation of the open-chain form are the same at pH 12.5, having a pseudo-first-order rate constant of k = 2.2 × 10-3 sec-1. The implications of these results are discussed in the light of current ideas on the acid-base dependence of thiamine structures.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19840670609
