17592-07-3Relevant articles and documents
Triene Photophysics and Photochemistry: Previtamin D3
Dauben, William G.,Share, Paul E.,Ollmann, Richard R., Jr.
, p. 2548 - 2554 (1988)
The origin of the wavelenght dependent photochemical behavior of previtamin D3 was investigated.The fluorescence spectrum and quantum yield of previtamin D3 were determined at 302 and 307 nm, and both the intensity distribution and the fluorescence quantum yields were found to be independent of excitation energy.A large Stokes shift was observed which is consistent with an excited state torsional relaxation about the central double bond of the triene.The excited state displacement was reproduced by QCFF/PI calculations of the ground and excited states of a model compound.The excited state involved in the absorption and emission spectra is discussed.
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van de Vliervoet et al.
, p. 1179,1182 (1956)
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Photo-conversion of two epimers (20R and 20S) of pregna-5,7-diene-3β, 17α, 20-triol and their bioactivity in melanoma cells
Zmijewski, Michal A.,Li, Wei,Zjawiony, Jordan K.,Sweatman, Trevor W.,Chen, Jianjun,Miller, Duane D.,Slominski, Andrzej T.
scheme or table, p. 218 - 228 (2009/04/14)
Pregna-5,7-dienes and their hydroxylated derivatives can be formed in vivo when there is a deficiency in 7-dehydrocholesterol (7-DHC) Δ-reductase function, e.g., Smith-Lemli-Opitz syndrome (SLOS). Ultraviolet B (UVB) radiation induces photoconversion of 7-DHC to vitamin D3, lumisterol3 and tachysterol3. Two epimers (20R and 20S) of pregna-5,7-diene-3β,17α,20-triol (4R and 4S, respectively) were synthesized and their UVB photo-conversion products identified as corresponding 9,10-secosteroids with vitamin D-like and tachysterol-like structures, and 5,7-dienes with inverted configuration at C-9 and C-10 (lumisterol-like). The number and character of the products and the dynamics of the process were dependent on the UVB dose. At high UVB doses, the formation of multiple oxidized derivatives of the primary products, and the formation of 5,7,9(11)-triene, were observed. The production of vitamin D-like, tachysterol-like and lumisterol-like derivatives was also observed in human skin treated with 4R and 4S, and subjected to UV irradiation, as shown by RP-HPLC. Newly synthesized compounds inhibited melanoma growth in dose dependent manner, and some of them showed equal or higher potency than 1,25(OH)2D3. In summary, we have characterized for the first time the products of UV induced conversion of pregna-5,7-diene-3β,17α,20-triols and documented that the newly synthesized compounds have antiproliferative properties against melanoma cells.
ROUTES TO OPTIMIZATION OF PREVITAMIN D PHOTOSYNTHESIS USING IRRADIATION BY A SUNLAMP
Terenetskaya, I. P.,Bogoslovskii, N. A.,Vysotskii, L. N.,Luknitskii, F. I.
, p. 589 - 596 (2007/10/02)
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