Dicentra eximia

Eukaryotes quantitated in various plants e.g. Phaseolus vulgaris, Pisum sativum (Fabaceae) fea mays (Poaceae) seedling tissues involvement in plant defence stomatal opening Annona squamosa (Annonaceae), Dicentra eximia, Corydalis ambigua (Fumariaceae), Beilschmiedia podagrica (Lauraceae), Eschscholzia californica, Glauciumflamm (Papaveraceae)... 

In the light of established pathways to aporphine alkaloids (see p. 15) study of the biosynthesis of glaucine (6) and related bases in Dicentra eximia might have been expected to yield orthodox results. On the contrary, however, a novel pathway was unearthed which implicates dienone intermediates of quite un-... 

Aporphine Alkaloids.—Isothebaine (65) derives from orientaline (62) along a pathway which involves thedienone(63)and the dienol(64). The biosynthesis of the aporphine alkaloids of Dicentra eximia is quite different but dienone intermediates are also implicated. By comparison the biosynthesis of bulbocapnine (66) is simple, for the alkaloid arises directly from reticuline (67), in Corydalis cava, by ortho-ortho phenol oxidative coupling. 

Occurrence. Coreximine, C19H21O4N, has been isolated only from Dicentra eximia (0.007%) (28). It crystallizes with great facility when a concentrated solution of it in chloroform is diluted with methanol. The colorless stout prisms thus obtained melt at 262° to an orange-colored liquid. 

The structures of the Dicentra eximia bases, glaucine [6.138) dicen-trine [6.140) and, particularly, corydine [6.139) indicate a similar pattern of biosynthesis to that already discussed. Quite unexpectedly the biosynthetic route turned out to be different. Painstaking work established [93] that biosynthesis is from norprotosinomenine [6.136) the likely following steps are indicated in Scheme 6.27 (the point of A -methylation is unknown). Boldine [6.131) is a logical, and... 

Diatraea grandiosella. See Southwestern corn borers Dicentra, 90-91 Dicentro eximia, 91 Dicentra spectahilis, 90 Dieback... 

Cularine, C20H23O4N, has been isolated from Dicentra cucuUaria (L.) Bernh., D. eximia (Ker-Gawl.) Torr., D. oregana Eastwood, D. formosa (Andr.) Walp., and Corydalis claviculata (L.) DC. (1, 2). Only in the last-named plant does it constitute a major constituent, but its presence in very minute amounts can be ascertained by virtue of the fact that it forms an acid oxalate which is virtually insoluble in cold water or methanol. It is, therefore, readily isolated from mother liquors from which other alkaloids have been separated either as free bases or as salts other than oxalates. It is readily extractable as its hydrochloride from aqueous solutions by means of chloroform and thus separates along with dicentrine, glaucine, bicuculline, corlumine, etc. 

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