Co-occurrence of two terpenoid isocyanide-formamide pairs in a marine sponge (Halichondria sp.)
作者:B.J. Burreson、C. Christophersen、P.J. Scheuer
DOI:10.1016/0040-4020(75)80189-x
日期:1975.1
From a marinesponge (Halichondria sp.) we have isolated amorphane sesquiterpenoids that are substituted at C-10 by isocyanide (1), formamide (2), and isothiocyanate (3), and diterpenoids that are 3,7,11,15- tetramethyl-1,6,10,14-hexadecatetraenes (geranyllinaloyl) bearing isocyanide (13), formamide (14), and isothiocyanate (16) functions at C-3.
The first nonracemic synthesis of (+)-geranyllinaloisocyanide, starting with (–)-lactic acid methyl ester, has been accomplished by exploiting a [3.3] sigmatropic rearrangement of allyl cyanate. The synthesis enables assignment of the S configuration of the C(3) isocyano substituted, quaternary stereogenic center in natural geranyllinaloisocyanide.