Photochemistry of Previtamin D3 at 92 K;
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Dr. Paul A. Maessen; Dr. Harry J. C. Jacobs; Prof. Dr. Jan Cornelisse; Prof. Dr.
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Article
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1983
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John Wiley and Sons
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English
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m.p.= 123-125 "C] from 11. 12 reacts with trimethyloxonium tetrafluoroborate to yield 3,6-bis[bis(methylthio)methylenel-1,4-dimethyl-2,5-bis(methylthio)3,6-dihydropyrazindium bis(tetrafluorob0rate) 13 [83%, orange needles, blackens above 225 "C; UV/VIS (CH,CN): A, , , (lgE)=205 (4.15), 300 (sh, 4.09