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Studies on vitamin D and related compounds XIV Investigations on sterols XVII: The photoisomerization of pre-ergocalciferol and tachysterol2

✍ Scribed by M. P. Rappoldt

Publisher
Elsevier Science
Year
2010
Tongue
English
Weight
389 KB
Volume
79
Category
Article
ISSN
0165-0513

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✦ Synopsis

Abstract

The quantum yields of the isomerizations of pre‐ergocalciferol and tachysterol~2~ in ether at 20Β° under the influence of ultraviolet light of 2537 Γ… were found to be 0.49 and 0.11 respectively. Ergosterol is not formed from tachysterol~2~ during irradiation but originates exclusively from pre‐ergocalciferol. The origin of lumisterol~2~ is somewhat less certain; it seems to be formed from tachysterol~2~.

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