The natural molecule 2-methylamino-1-phenyl-1-propanol has 2 chiral centers and is derived from the Chinese shrub Ma Huang. The shrub contains 2 physiologically active compounds ephedrine and pseudoephedrine-both of which are stereoisomers of the molecule 2-methylamino-1-phenyl-1-propanol. Each compound has an enantiomer, which isn’t found in the natural shrub but can be synthesized. The two active compounds can not be enantiomers as they have such different properties. Ephedrine has a melting point of 35-40*c and pseudophedrine has a melting point of 119*C. Pseudoephedrine, in particular, can be used as a decongestant and the salts pseudoephedrine hydrochloride and pseudoephedrine sulfate help to relieve nasal/sinus problems-it can be found in many common prescription or over-the-counter drugs such as Sudafed. Pseudoephedrine works by shrinking the blood vessels in the nasal passage as this is what can cause a blocked nose. Some ADHD patients have also been prescribed pseudoephedrine due to its properties as a stimulant. The drug, along with many others, works by having a calming effect on the patient.