【How-to】How to make bathtub crank

Pseudoephedrine was first known as a natural substance that occurs in shrubs of the Ephedra genus, which grow worldwide. Almost all commercial pseudoephedrine, however, is produced by fermenting dextrose in the presence of benzaldehyde. The primary product, (R)-phenylacetylcarbinol, is aminated to make pseudoephedrine.