Forsythide

The aglucone of the dimethyl ester of forsythide (105)195 has been synthesized according to Scheme 9 196 when the aldehyde produced by photolysis of the... 

Three other structurally related oxygenated bicyclic molecules are verbenalol (242), iridomyrmecin (247), and forsythide aglycone dimethyl ester (256). All have been synthesized in racemic form. Sakan and Abe s preparative route to 242 is elegantly designed (Scheme 37).301) Readily available ketone 234 was treated in turn... 

The first of these proposals (Scheme 2) is based on feeding experiments [25] in Forsythia viridissima and Forsythia europea. The C-10 site of deoxyloganic acid is oxidised to alcohol to give adoxosidic acid, and further oxidation at the same position result in forsythide which, in turn, must be the common origin to a series of derivatives found in Forsythia. This route may be exclusive for this tribe. 

Damtoft et al. carried out feeding experiments in Forsythia viridissima and F. europaea using deuterium-labeled deoxyloganic acid and found incorporation into forsythide (36). On the basis of the results, they concluded that deoxyloganic acid was oxidized at C-10 to adoxosidic acid followed by further oxidation at C-10 to forsythide in Forsythia spp. [71]. 

Inouye H, Nishioka T (1973) Uber die monoterpenglucoside und verwandte naturstofre. XX. liber die struktur des forsythids, eines neuen iridoidglucosides aus Forsythia viridissima. Chem Pharm Bull 21 497-502... 

Liao, C.-C. and Wei, C.-P., Synthetic applications of masked o-benzoquinones. A novel total synthesis of ( ) forsythide aglucone dimethyl ester, Tetrahedron Lett., 30, 2255,1989. 

Takemoto, T. and Isoe, S., Tricyclo[3.3.0.0 > ]octanones as building blocks in natural product synthesis. Synthesis of ( ) forsythide aglycone dimethyl ester, Chem. Lett. 1931, 1982. 

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