Amoxicillin

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Amoxicillin

OVERVIEW

Amoxicillin (uh-MOX-uh-sill-in) is also known as D-(-)-alpha-amino-p-hydroxybenzyl penicillin and (2S,5R,6R)-6-[(R)-(-)-2-amino-2-(phydroxyphenyl)acetamido]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid. It is an off-white crystalline antibiotic, a substance that inhibits the growth of microorganisms. It is generally available in the form of the trihydrate (having three molecules of water for each molecule of amoxicillin) with the formula C₁₆H₁₉N₃O₅S·₃H₂O. Amoxicillin is effective against a number of disease-causing bacteria, including streptococci, the bacterium that cause strep throat, and most strains of pneumo cocci, the bacterium that cause pneumonia, gonococci, the bacterium that cause gonorrhea, and meningococci, the bacterium that cause meningitis. Amoxicillin works by blocking the formation of bacteria cell walls. Without cell walls, the bacteria die.

KEY FACTS

OTHER NAMES:

See Overview.

FORMULA:

C₁₆H₁₉N₃O₅S

ELEMENTS:

Carbon, hydrogen, nitrogen, oxygen, sulfur

COMPOUND TYPE:

Organic (pharmaceutical)

STATE:

Solid

MOLECULAR WEIGHT:

365.40 g/mol

MELTING POINT:

No data available

BOILING POINT:

No data available

SOLUBILITY:

Soluble in water and alcohol; insoluble in most organic solvents

Amoxicillin belongs to a group of semisynthetically produced antibiotics called the aminopenicillins. The term semisynthetic means that some stages in the preparation of the compound make use of naturally-occurring organisms, such as bacteria or yeast, and some stages involve chemical synthesis. Preparation of the aminopenicillins begins with the antibiotic penicillin itself, usually made by one of the molds in the Penicillium family, such as Penicillium chrysogenum or Penicillium notatum. The penicillin molecule is then modified by the addition of a hydroxyl, methyl, or some other group. Other semisynthetic antibiotics related to amoxicillin and penicillin are ampicillin, benzylpenicillin (penicillin G), and phenoxymethylpenicillin (penicillin V).

Scottish bacteriologist Alexander Fleming (1881–1955) discovered penicillin in 1928. The antibiotic was first produced for human use in the early 1940s. Over time, researchers discovered ways of changing the chemical structure of penicillin to create semisynthetic versions. The new antibiotics they created were more effective than penicillin against a wider range of bacteria, often with fewer side-effects. Amoxicillin was discovered by researchers at the Beecham pharmaceutical laboratories in 1962 and marketed about a decade later under the trade name of Amoxil®. The drug is now available under a number of trade names, including Larotid®, Trimox®, Wymox®, Polymox®, and Augmentin®.

HOW IT IS MADE

The preparation of amoxicillin involves a complex series of reactions that begins with penicillin produced by molds or other microorganisms. A variety of chemical reagents is then used to replace one hydrogen atom in the penicillin molecule by the CH(NH₂)C₆H₄OH group that converts penicillin into amoxicillin.

COMMON USES AND POTENTIAL HAZARDS

Amoxicillin is available only by prescription and is used against a variety of disease-causing bacteria, such as the cocci bacteria listed above, as well as Bordetella pertussis, the bacterium that causes whooping cough, Salmonella typhi, the bacterium that causes typhoid, and Vibrio cholerae, the bacterium that causes cholera.

Interesting Facts

The original U.S. patent on amoxicillin granted to Beecham Laboratories in 1965 has expired, allowing other pharmaceutical manufacturers to make the drug. This fact accounts for the more than three dozen trade names under which it is sold.

The safety of amoxicillin has been extensively tested in trials with both experimental animals and humans. It poses no risk to the vast majority of people. As with all drugs, however, some individuals may experience adverse reactions to the use of amoxicillin. These reactions include fever, skin rash, joint pain, or swollen glands. More serious reactions can include nausea, diarrhea, or anaphylaxis, a potentially fatal allergic reaction. Adverse reactions are most likely to occur among people who have asthma, kidney disease, leukemia, intestinal problems, chronic illness, or a known allergy to other penicillin drugs.

Words to Know

ANAPHYLAXIS: A serious allegic reaction to a substance that may include respiratory symptoms, fainting, swelling and itching.
REAGENT: A substance used in a chemical reaction.
SEMISYNTHETIC: A compound that is prepared in such a way that some stages in the preparation use naturally-occurring organisms, such as bacteria or yeast, and some stages involve chemical synthesis.
SYNTHESIS: A chemical reaction in which some desired chemical product is made from simple beginning chemicals, or reactants.