[Existence of "pangamic acid" alias "vitamin B 15"?]

At least 10 pharmaceutical and 3 homeopathic products that supposedly contain "pangamic acid" or "vitamin B-15" are commercially available in the Federal Republic of Germany including Berlin (West) and other European countries. However, neither the structure of "pangamic acid" or its analogs nor its existence in natural or synthetic products has been ascertained. This is a challenge for most interpretations of animal experiments and medicinal applications. Calling "pangamic acid"-compounds "vitamin B-15" is scientifically untenable.