Larkspur, garden

Ajaconine, the major alkaloid of the seeds of Delphinium ajacis syn. Consolida ambigua (garden larkspur) and D. consolida, has been known since 1913 (S3). Recently, ajaconine has been isolated from the whole plants of D. virescens Nutt (84) and D. carolinianum (85), two relatively rare plants native to the southeastern United States. In 1961, Dvornik and Edwards (86) reported a full account of the structure elucidation of ajaconine as 80. 

During the mass spectral studies of diterpenoid alkaloids of the seeds of garden larkspur (Consolida ambigua ), Waller and his co-workers (134) reported the presence of delcosine (163), acetyldelcosine (164), and delsoline (165). The mass fragmentation patterns of these alkaloids will be discussed in Section VI. 

This plant (garden larkspur) is designated in the older literature as D. ajacis. It is now correctly named as Consolida ambigua (L.) P. W. Ball Heywood (C. S. Keener, Castanea, 41, IS (1976)). In our review the name Consolida ambigua will be used to designate the garden larkspur. 

Alkaloids from Consolida ambigua-. Dihydroajaconine.— With the C19 diterpenoid alkaloids discussed in Section 2, dihydroajaconine, C22H35NO3, m.pt. 99—100 °C, was isolated from C. ambigua (garden larkspur). It was obtained from the mother liquors of the ajaconine isolation. Structure (58) for dihydroajaconine was proposed on the basis of the spectral data and confirmed by reduction of ajaconine (59) to (58) by borohydride. 

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