Hydrolysis of hordein : by Thomas B. Osborne and S.H. Clapp.

Thomas Burr Osborne

Date:: [1907]

Credit: Hydrolysis of hordein : by Thomas B. Osborne and S.H. Clapp. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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$* • OAO Dissolved in 20 per cent hydrochloric acid (a) _ = +26.95°. Fraction. Ill Temp, of bath up to Pressure. 100° 0.48 mm. Weight. 137.2 gm. This fraction consisted mainly of the ester of a proline. It was saponified by boiling with water to the cessation of the alkaline reac- tion and the solution rapidly evaporated to dryness under strongly reduced pressure. The part remaining undissolved in absolute alco- hol consisted almost wholly of leucine. The yield was 30.89 gm. Carbon and hydrogen, 0.1946 gm. subst., gave 0.3930 gm. C02 and 0.1746 gm. H2O. Calculated for C6H1302N = C 54.96 ; H 9.92 per cent. Found . . . . = C 55.08; H 9.97 “ “ The substance decomposed at about 298°. The alcohol solutions of the proline of Fractions II and III were united. After concentrating under reduced pressure and precipitat- ing with ether, the substance was obtained as a white crystalline mass, which when carefully dried weighed 86.32 gm. On redissolv- ing in absolute alcohol, the proline separated in the characteristic prisms, melting at 200°-205°. Carbon and hydrogen, 0.2737 Sm- subst., gave 0.5235 gm. C02 and 0.1981 gm. H2O. Calculated for C5H902N = C 52.18 ; H 7.83 per cent. Found . . . . = C 52.16; H 8.04 “ “ For the strict identification, the substance was converted into the copper-salt and by boiling the latter with alcohol, the laevo separated from the racemic. The insoluble copper-salt of laevo-proline crystallized from water in the characteristic plates containing two molecules of water-of- crystallization. Water, 0.3447 gm. subst. (air-dried), lost 0.0377 gm. H.,0 at no°. Calculated for C10HlcO4N2Cu • 2H20 = H20 10.99 per cent. Found = HoO 10.94 “ “ Copper, 0.3026 gm. subst., gave 0.0817 gm. CuO. Calculated for CioH1i;04N3Cu = Cu 21.Si per cent. Found = Cu 21.57 “ “ The phenylhydantoine of the laevo-proline melted at 143°-$

Hydrolysis of hordein : by Thomas B. Osborne and S.H. Clapp.

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