Edinburgh Research Archive logo

Edinburgh Research Archive

University of Edinburgh homecrest
View Item 
  •   ERA Home
  • Chemistry, School of
  • Chemistry thesis and dissertation collection
  • View Item
  •   ERA Home
  • Chemistry, School of
  • Chemistry thesis and dissertation collection
  • View Item
  • Login
JavaScript is disabled for your browser. Some features of this site may not work without it.

Methionine, a naturally occurring amino acid containing sulphur: an investigation into the structure and a synthesis

View/Open
CoyneFP_1928redux.pdf (8.901Mb)
Date
1928
Author
Coyne, Frederick Philip
Metadata
Show full item record
Abstract
 
 
(1) Isolation of amino acid.
 
Mueller obtained the amino acid by precipitation with mercuric sulphate after hydrolysis of casein. The precipitate was decomposed with baryta, the barium and mercury removed with sulphuric acid and hydrogen sulphide respectively and the solution evaporated to small volume. A second precipitation, this time with mercuric chloride, was brought about, and the precipitate was decomposed by passing hydrogen sulphide into an aqueous suspension. The silver oxide method was used to obtain the free amino acid which was finally crystallised from 75 per cent. alcohol. This method did not give a pure product, the chief contamination being apparently phenyl alanine. By repeating the mercuric chloride precipitation, the substance was obtained pure, but only at the expense of a large loss. The yield of crude product varied from 1 -2 grams per lb. of casein. The same method used with gelatin gave smaller yields.
 
(2) Investigation of structure of amino acid.
 
The first experimental work carried out with the amino acid was a repetition of Mueller's comparison with ethyl cysteine. The results obtained confirmed his statement regarding their relative stabilities to alkali.
 
(3) Synthesis of amino acid.
 
The methods of synthesis of amino acids used by Erlenmeyer and by Strecker were considered.
 
(4) Derivatives of amino acid.
 
The α-naphthyl isocyanate described by Mueller was prepared and the synthetic and natural products were again identical. Further confirmation was obtained by the preparation of the thio hydantoin and the picrolonpate. In each case the products from the synthetic and natural amino acid were identical.
 
URI
http://hdl.handle.net/1842/30133
Collections
  • Chemistry thesis and dissertation collection

Library & University Collections HomeUniversity of Edinburgh Information Services Home
Privacy & Cookies | Takedown Policy | Accessibility | Contact
Privacy & Cookies
Takedown Policy
Accessibility
Contact
feed RSS Feeds

RSS Feed not available for this page

 

 

All of ERACommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsPublication TypeSponsorSupervisorsThis CollectionBy Issue DateAuthorsTitlesSubjectsPublication TypeSponsorSupervisors
LoginRegister

Library & University Collections HomeUniversity of Edinburgh Information Services Home
Privacy & Cookies | Takedown Policy | Accessibility | Contact
Privacy & Cookies
Takedown Policy
Accessibility
Contact
feed RSS Feeds

RSS Feed not available for this page