The stereochemistry of hyoscine / by Harold King.

  • King, Harold.
Date:
1919]
Catalogue details

Licence: Public Domain Mark

Credit: The stereochemistry of hyoscine / by Harold King. Source: Wellcome Collection.

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    of the base was prepared in aqueous solution by combination with one equivalent proportion (045 gram) of d-tartaric acid. On con¬ centrating the solution to about 10 c.c., apohyoscine ^-hydrogen tartrate crystallised in clusters of radiating, white needles. The product was collected and washed with water. When dried in the air, it amounted to 1*15 grams. It was recrystallised four times from water, the properties of the successive fractions being as follows: I. 1*15 grams, m. p. 97°, [a]D + 8'74D. II. 1*0 gram, ,, 95—97°, Md + 8'35u. III. 0*75 ? y „ 95—97°, [«]d + 7'78°. IV. 0*45 )} „ 95—97°, [o]D + 8'59°. Employing Landolt’s value, [M]D+42*84°, for ammonium hydrogen tartrate, the calculated value for ^-apohyoscine 6?-hydrogen tartrate is [o]D + 9*1°, in approximate agreement with the values recorded above. The base when recovered from the fourth fraction was examined in absolute alcohol, but the solution was devoid of optical activity. dl-apoHyoscine d-hydrogen tartrate is sparingly soluble in cold, but dissolves freely in hot water. It crystallises with two mole¬ cular proportions of water in clusters of long needles. In a capillary tube it melts at 95—97° (95—97° corr.), and effervesces at 115°, but it melts below 90° when exposed on a watch-glass to a temperature of 90—95°. The water of crystallisation is not lost when the salt is dried in a vacuum over sulphuric acid: 0*1037, air-dried, gave 0*2031 C02 and 0*0579 H20. C = 53*4; H = 6*2. C17H1903N,C4H606,2H20 requires C = 53'5; H = 6*2 per cent. The specific rotation was determined in dilute aqueous solution, using the air-dried salt. c = 2*008; 1= 2-dcm.; a+0*345°; [a]D +8*6°; [M]D +40*5°. d-Hyoscine Camphor-fi-sulphonate. Almost pure e£-hyoscine base (1*5 grams) was neutralised with camphor-/3-sulphonic acid (1*15 grams). The syrupy salt was obtained crystalline by boiling with anhydrous ethyl acetate. It amounted to 2*3 grams and had [a]D +27*6°. It was recrystallised thrice more from anhydrous ethyl acetate, the specific rotation of the three fractions being successively [o]D +29*5°, +29*4°, +29*3°. The final fraction amounted to 1*5 grams. d-Hyoscine camphor-fi-sulphonate crystallises well from anhydrous