Thursday, March 24, 2011

Aspartic Acid

  Aspartic acid is a non-essential and acidic amino acid.  Aspartic acid is abbreviated as Asp or D.  Aspartic acid was first recognized in 1868 when it was first isolated from legumin in plant seeds.  Aspartic acid is a non-essential amino acid for mammals which means that enough aspartic acid is synthesized by the body from oxaloacetic acid which is formed in metabolism of carbohydrates.  Aspartic acid is found in many different sources of food such as dairy, beef, poultry and sprouting seeds.  Here is a high quality representation of the structure of aspartic acid:

  Aspartic acid's molecular formula is C4H7NO4 and has a molecular weight of 133.10 grams/mole. Aspartic acid is the one of only two amino acids that give a negatively charged carboxylic group on the side chain.  The functional groups present within aspartic acid are an amine and two carboxylic groups.  Aspartic acids are play a vital role as acids in enzyme active centers and also function in maintaining the solubility and ionic character of proteins.  This amino acid is one of the only two acidic amino acids.  There are three pKa values for aspartic acid which are: 1) alpha-carboxylic - 2.10;   2) alpha-amino -  9.82;  3) side chain  -  3.86.  The side chain is a carboxyl group located on the amino acid.  The isoelectric point for aspartic acid is 2.77 pH. 
 
Sources:
1.  Mayer, Michael. "Aspartic acid information page. All about aspartic acid and the role it plays in your diet." Zest for Life vitamins and supplements. 24 Jan. 2011. 24 Mar. 2011 http://www.anyvitamins.com/aspartic-acid-info.html.

2.  Kirste, Burkhard. "Aspartic Acid." Institut für Chemie und Biochemie an der FU Berlin. 23 Jan. 1998. 24 Mar. 2011 http://www.chemie.fu-berlin.de/chemistry/bio/aminoacid/asp_en.html.

3.  "Amino Acids - Aspartic Acid." The Biology Project. 24 Sept. 2003. 24 Mar. 2011 http://www.biology.arizona.edu/biochemistry/problem_sets/aa/aspartate.html.

4.  Parrill, Abby. "Amino Acid Structures." Michigan State University. 4 Feb. 1997. Department of Chemistry. 24 Mar. 2011 http://www.cem.msu.edu/~cem252/sp97/ch24/ch24aa.html.

Sunday, March 6, 2011

Ibuprofen

  The fourth blog assignment was to find an article containing a synthesis of a common drug and to list any of the Electrophilic Aromatic Substitution reactions in the synthesis.  After thoroughly looking through many websites and journals I finally found an article that had a synthesis for a common drug and that drug is...IBUPROFEN!
  Ibuprofen is an over the counter drug which is used to relieve pain of symptoms of arthritis, fever and other occurrences for pain relief.  It was developed in the 1960s and was discovered by Steward Adams in 1961 and also patented in the same year.  Ibuprofen functions as an inhibitor for an enzyme that directs formation of several mediators of inflammation.
  There are five steps in the synthesis of ibuprofen.  The first step is the electrophilic aromatic substitution step where a Friedel-Crafts acylation occurs. The isobutyl group is a ortho and para director and a benzene activator.  However, the para isomer is formed because there is steric hindrance on the ortho isomer.  The next few steps involve the reduction of the ketone to an alcohol, then conversion of alcohol to a chloro group, then the chloro group is substituted by a cyano group.  The last step involves the hydrolysis of the cyano compound to achieve the final product of ibuprofen.  Listed below is the synthesis:


  The site were the article can be found is:
    http://www.pharmainstitute.in/archives.htm  on the May 2008 issue
Hope this is interesting and allows you to understand electrophilic aromatic substitution in a different way with an actual synthesis of a common everyday drug.