Bufothionine
Bufothionine is a sulfur-containing compound which is present in the bufotoxins secreted by the parotoid gland of certain toads of the genera Bufo and Chaunus. The structure has been shown by X-ray crystallography to be (1,3,4,5-tetrahydro-5,5-dimethylpyrrolo-[4,3,2-de]quinolinio)-6-sulfate.