Benfotiamine is a lipid-soluble form of thiamine (vitamin B-1).  It was developed in Japan in the early 1960's and the Germans have long used it to treat alcoholic neuritis. It is the most effective metabolic precursor of active thiamine, or vitamin B1, available. One of the best description of benfotiamine I have found was assembled by AOR, a Canadian nutraceutical company:  Abstracts & Summary Description of Benfotiamine. 

For you science geeks, here is the benfotiamine molecule: