"Conclusion-

     With the current knowledge of the role of thiamine in cell metabolism, we can assess the effects of its deficiency
as well as the mechanisms and effects of thiamine antimetabolites on our organisms. As a result of this knowledge,
both thiamine and its antimetabolites are becoming increasingly use in medicine and veterinary practice. Thiamine
used as a dietary supplement is important for improving the well being of older people, especially those affected by
neurodegenerative diseases. It is recommended by geriatrics, neurologists, and cardiologists to use it in appropriate
doses and easily absorbed form (such as benfotiamine). Therefore, research on the process of absorption of thiamine
and finding its well-absorbed forms as well as defining of groups of risk of thiamine deficiency become a great interest
of medical doctors.

Taking into consideration the above mentioned results of many studies, thiamine antivitamins could be consid-
ered as useful additional agents in the therapy of cancer, superficial mycoses (especially these caused by species which

cannot provide fermentative metabolism like Malassezia), and bacterial infections. Introducing new therapies is very

important in terms of bacteria and fungi increasing drug resistance. From this point of view, synthesis of new thi-
amine derivatives based on strong thiamine diphosphate-dependent enzymes inhibitors is very interesting scientific

task. The use of new theoretical and organic chemistry tools provides opportunities for the design and synthesis of
compounds with desirable affinity to target proteins in the cell. Comparing the effects of new derivatives with known
anticoenzymes on the level of thiamine diphosphate-dependent enzymes and pathogenic yeast, bacteria and cancer
cells, we can estimate the utility of obtained derivatives and show perspectives for their practical use in medicine.
On the other hand, recent research of Zhang et al. [132] indicates that we can be exposed to trace amounts of

thiamine antimetabolites like oxythiamine as a result of thiamine transformation through cooking under acidic con-
ditions at 100?C. That kind of contamination may cause undesirable effects on our metabolism (e.g. transketolase

inhibition in dialyzed patients with end-stage renal disease). Poultry fed with amprolium as a means of preventing

coccidiosis as well as post-production impurities from poultry farms may be also potential sources of thiamine an-
timetabolites contamination. From this point of view, there is a need for intensive development of new methods for

the measurements of thiamine antimetabolites in food, feedstocks, and environment in order to constant monitoring
of the level of contamination and prediction of the possible effects of thiamine antimetabolits pollution for people
health.

Acknowledgments The authors would like to thank the Computer Center of the University of Bialystok

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