The Croonian lectures on some points in the pathology of rheumatism, gout and diabetes : delivered at the Royal College of Physicians, London, March 30, April 1, 6, 1886 / by P. W. Latham, M.A., M.D., F.R.C.P.
- Peter Wallwork Latham
- Date:
- 1887
Licence: Public Domain Mark
Credit: The Croonian lectures on some points in the pathology of rheumatism, gout and diabetes : delivered at the Royal College of Physicians, London, March 30, April 1, 6, 1886 / by P. W. Latham, M.A., M.D., F.R.C.P. Source: Wellcome Collection.
Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.
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![Leucine is very largely diffused in the animal organism, and may be obtained by various processes from albumen, flesh, gelatine, casein, &c.* By oxidising amylic alcohol with potassium chromate and sulphuric acid, and distilling, we obtain amylic or valerianic alde- hyde t— C,H^,.HO + O = C^H^.CHO + H,0 amylic alcohol valerianic aldehyde Mixed with aqueous ammonia the aldehyde is converted into valeral ammonia, and this digested with hydrocyanic acid and hydrochloric acid is converted into leucine— C^H^. CHO + NH3 = C^Hg. CH (NH,) 0H + valerianic aldehyde valeral ammonia. C,H,. CH (NHJ. 0H+ HCN + H,0 = C^H^. Ch|^^jj + NH3§ valeral ammonia leucine This is the usual way of obtaining leucine artificially; but Tiemann has shown II that the amido-acids, both of the fatty and * Watts, Dictionary, Vol. iii. p. 574. + lb. Vol. V. p. 973. t lb. Vol. V. p. 974. § Fownes, Manual of Org. Chem., 1877, p. 385. II Berichte der deutsch. chem. GeselL, xiv. s. 1985. The amido acids of the fatty series are easily obtained by the familiar reactions which take place on treating aldehyde ammonia with hydrochloric and hydrocyanic acids, and which led Strecker to the discovery of alanine The reactions indicated by Strecker take place unquestionably according to the following general formul£e: (NH2 (NH3 B... c]h + HCN = E...C KH +H,0, (oh (cn and E... C H + 2H2O + HCl = B... CH (NH^)... COOH + H^NCI. (cN](https://iiif.wellcomecollection.org/image/b21445278_0013.jp2/full/800%2C/0/default.jpg)
