Bisditerpenoid alkaloid

The alkaloids of Delphinium staphisagria have been reviewed. Delphidine has been shown to possess the structure (106) whilst delphirine (107) possesses the unusual C-1 hydroxy-group. Staphigine and staphirine are bisditerpenoid alkaloids which have been obtained " from D. staphisagria. Examination of D. tricorne afforded " a new alkaloid tricornine (108) which was shown to be 18-acetyl-... 

Recently, a new class of diterpenoid alkaloids, known as bisditerpenoid alkaloids, has been isolated from the seeds of Delphinium staphisagria (2). The bisditerpenoid alkaloids (e.g., staphisine, iv) may be formally derived by... 

Besides the two bisditerpenoid alkaloids discussed earlier, two new imine-containing alkaloids designated as staphinine and staphimine have been isolated (148) from the seeds of D. staphisagria. The structures of staphinine (188) and staphimine (189) were also assigned on the basis of 13C- and H-NMR spectral analysis. 

It is interesting to note that these two bisditerpenoid alkaloids did not contain the conjugated diene system, which is present in the other six bisditerpenoid alkaloids. Biogenetically, it is worth noting that all these bisditerpenoid alkaloids occur as methoxyl and desmethoxyl pairs in the seeds of D. staphisagria. 

The power of the 13C-NMR spectroscopic technique was demonstrated (148-150) in the elucidation of the structures of some very complex natural products, the bisditerpenoid alkaloids, isolated from D. staphisagria. On the basis of l3C-NMR data of the known alkaloid, staphisine (185), the structures of seven new related alkaloids, staphidine (187), staphinine (188), staphimine (189), staphigine (190), staphirine (191), staphisagnine (193),... 

Research on diterpenoid alkaloids published during the past year has continued to expand the body of structural and synthetic information available on these complex plant bases. The structures of ten new alkaloids from Aconitum and Delphinium species, including seven new bisditerpenoid alkaloids, have been reported. Tlie most significant progress in methods of structure elucidation has been the very successful applications of n.m.r. to the study of complex diterpenoid alkaloids. The New Bruns wick group under Professor Karel Wiesner has continued its progress toward the syntheses of the Ci9-aconitine-type alkaloids. An historical account of the synthesis of talatisamine (1), the first synthesis of a hexacyclic aconite alkaloid, has been published. This work was reviewed in a previous Report. ... 

Diterpenoid Alkaloids.— The alkaloids of Delphinium staphisagria include some bisditerpenoid alkaloids such as staphidine, staphinine, and staphimine. The full paper has appeared on the structure and stereochemistry of delphisine, neoline, chasmanine, and homochasmanine. The application of n.m.r. measurements to these alkaloids has led to the revision of the structure of the alkaloid A from D. bicolor... 

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