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SECTIONAL TRANSACTIONS.—B. 363 
in doses of approximately 12y/diem (y=1/1,000 mg.) have been obtained, the corre- 
sponding value for Jansen’s erystals from rice polishings being 8y. The methods 
used are aqueous extract, purification with lead acetate, baryta and mercuric sulphate, 
followed by absorption upon charcoal at pH 7:0. By successive treatment with 
dilute HC! (X extracts) and alcoholic HCl (Y¥ extracts), it is found that X contains 
mostly B,, whereas Y, B,, B, and B;. Both arefree from B,. Alcohol fractionation 
combined with new methods of using phosphotungstic acid rapidly gives material of 
50y/ diem, and the constancy of precipitation of B, with phosphotungstate at pH 5-0- 
7-0 shows that this is a property of B,. B, is soluble in absolute alcohol as hydro- 
chloride (so also B, and B;). It is insoluble in lipoid solvents. Much impurity may 
mask these solubilities. It is resistant to acid hydrolysis, withstanding even boiling 
with strong nitric acid; it resists oxidising and reducing agents, also treatment 
with nitrous acid, but is inactivated by alkali. The facts suggest a tertiary base 
which is also supported by the pH at which pure B, is absorbed upon charcoal, 
pH 9-0 (Phelps). The reaction given by amounts of B, of two- to four-day doses with 
diazotised sulphanilic acid (Pauly reaction) is yellow with a trace of pink; the pink 
colour is enhanced, however, by choice of a suitable alkalinity for the coupling. 
Vitamin B,, often confused with B, in curative rat tests, is apt to accompany B, 
closely, being present in a sample of Jansen’s crystals recently tested. Difference 
from B, is established by (a) separation by adsorption upon charcoal at acid pH 
prior to adsorption of B,, and (b) the wide divergence between the ratio B,/B, in 
different X and Y concentrates. Following the tryptophane closely, it is precipitated 
by mercuric sulphate and disappears upon prolonged treatment with dilute acid. 
Vit. B; tends to follow B, in phosphotungstic fractionation, and is probably basic. 
Tt seems more stable to alkali than B,. By the use of the pure 24 phosphotungstic 
acid it is hoped to obtain sharp separation of B,, B, and B;. Vitamin B, is not 
extracted from wheat germ by warm 97 per cent. alcohol. When combined, it with- 
stands heat, and also acid hydrolysis, but rapidly disappears when liberated from 
combination. This constitutes a difference from other factors. 
Prof. J. C. Drummonp. 
(c) The Chemistry of Vitamin D and Related Sterols. 
Mr. R. B. Bourpinton and Dr. R. K. Cattow.—Crystalline Preparations 
of Vitamin D. : 
Attempts to isolate a crystalline vitamin D from the resinous mixtures obtained 
by the ultra-violet irradiation of ergosterol have now been partially successful in three 
different countries. In England a group of workers at the National Institute for 
20 ° 
Z Bit 260 
(in alcohol), by vacuum distillation of irradiation products of ergosterol, in a still 
designed to secure fractional condensation of the vapours. This product appears to 
form esters, and to be an isomeride of ergosterol. In Germany Prof. Windaus has 
removed some of the irradiation products of ergosterol by condensation with maleic 
anhydride, and has obtained from the residues a crystalline product somewhat similar 
to the English one, but showing an appreciably lower specific rotation. In Holland 
Drs. Reerink and van Wijk have obtained a crystalline product by irradiating ergos- 
terol under very carefully controlled conditions. The physical properties of this 
product have not yet (July, 1931) been fully described, but it appears to be more 
easily oxidised, and to have lower detro-rotation than the other two crystalline 
products. 
It is suggested that all three products may be mixtures in different proportions of 
two nearly isomorphic antirachitic compounds, one showing a high dextrorotation 
and considerable stability, and the other less stable and with laevorotation or low 
Medical Research have obtained a crystalline product of m.p.124° C and ae 
f dextrorotation. 
Prof. A. Winpaus (not communicated in person). 
The physical and chemical properties of ergosterol will be considered, with especial 
reference to its behaviour on hydrogenation, dehydrogenation and oxidation. Mention 
