Pyrrolophenanthridine alkaloid

Pyrrolophenanthridines and Related Alkaloids Lycorine and Related Alkaloids Galanthamine and Related Alkaloids Crinine and Related Alkaloids Tazettine and Related Alkaloids... 

A definite picture of the biosynthesis of norpluviine (10), the key intermediate to the pyrrolophenanthridine, and the lycorenine-type alkaloids was derived from two sets of feeding experiments. 

This method can be applied to the total synthesis of natural products. The lycorine alkaloids anhydrolycorinone and hippadine have a pyrrolo[3,2,l-de]phenanthridine framework and have been isolated from Amaryllidaceae plants [26]. Hippadine exhibits reversible inhibition of fertility in male rats. Diverse synthetic approaches to the pyrrolophenanthridine alkaloids have been developed because of their potent biological activities [27[. We applied the iron(O)-mediated arylamine cydization described above to a concise synthesis of anhydrolycorinone and hippadine (Scheme 15.7) [28]. 

The total synthesis of the pyrrolophenanthridine alkaloid, hippadine, was accomplished in the laboratory of T. Sakamoto. The last and key step of the synthetic sequence was the Stille-Kelly coupling of the A/-benzoylated indole precursor in 68% yield. 

A chloroacetylarylamine (90.9, n = I) may be converted into quinolin-2-one [2960] by treatment with the Vilsmeier reagent (review [1676]). A novel method of forming this ring was recently described as a stage in the synthesis of pyrrolophenanthridine alkaloids such as ungeremine. A C—C bond is formed by a radical mechanism of debromination by benzyl triethylammonium chloride... 

Moore s group has also exploited his methodology for the synthesis of a variety of 7V-heterocyclic quinones and hydroquinones such as piperidinoquinones 37, dihydrophenanthridinediols 38, benzophenanthridine 39, and assoanine 40, a member of a series of biologically active pyrrolophenanthridine alkaloids. ... 

Applicalion of this methodology toward the synthesis of oxoassoanine (298) [108] and anhydrolycorin-7-one (299) was also carried out [109]. These compounds are members of the pyrrolophenanthridine class of alkaloids, which have... 

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