Glucosamine Sulfate

Glucosamine (C6H13NO5) is an amino sugar and a prominent precursor in the biochemical synthesis of glycosylated proteins and lipids. Glucosamine is part of the structure of two polysaccharides, chitosan and chitin. Glucosamine is one of the most abundant monosaccharides.[2] Produced commercially by the hydrolysis of shellfish exoskeletons or, less commonly, by fermentation of a grain such as corn or wheat. Glucosamine has various names depending on the country and its intended use.   Glucosamine is a dietary supplement and is not a prescription drug in the United States.   https://en.wikipedia.org/wiki/Clinical_trials_on_glucosamine_and_chondroitin