Jan A. Glinski

The Diterpenoid Alkaloids of Delphinium Tatsienense Franch

From the roots of Delphinium tatsienense Franch (Ranunculaceae) two new and six known alkaloids have been isolated. The isolation and structure determination of deacetylambiguine (2) and a novel C 19 -diterpenoid alkaloid designated as tatsiensine (1) are described. The structure of tatsiensine was established on the basis of spectroscopic data and correlation with delpheline (12). Deacetylambiguine (2) has been isolated for the first time from a natural source. The known alkaloids that were isolated are the C 19 -diterpenoid alkaloids, browniine (3), delcosine (4), lycoctonine (8), and the C 20 -alkaloids ajaconine (6), hetisine (7) and hetisinone (5).

Hetisine derivatives. Part 1. Acetylation and oxidation of hetisine

Acetylation of hetisine (1) under drastic conditions afforded 2-acetyl (8), 11-acetyl (9), 13-acetyl (5), 2,11-diacetyl (7), 11,13-diacetyl (2) and 2,11,13-triacetyl (6) hetisines. Sarett oxidation of the compounds (9), (5), (7) and (2) gave 11-acetyl-2,13-didehydro (11), 13-acetyl-2,11-didehydro (12), 13-dehydro-2,11-diacetyl (14) and 2-dehydro-11,13-diacetyl (10) hetisines, respectivsly. Alkaline hydrolysis of (12) and (8) gave 2,11-didehydrohetisine (13) and 2-dehydrohetisine (hetisinone) (3), respectively. Sarett oxidation of hetisine (1) afforded (13) as the major product besides 11-dahylrohetisine (15). All the compounds have been characterized by their ir, ms, 1 H nmr and 13 H nmr data. The location of keto groups in the hetisine derivatives (3), (10), (11), (12), (13), (14) and (15) has been confirmed by CD and ORD meaeurements.

The structures of four new C 19 - diterpenoid alkaloids from Aconitum forrestii stapf

From the root extracts of Aconitum forrestii Stapf, we have isolated four new alkaloids: acoforine (6), acoforesticine (8), acoforestine (10) and acoforestinine (14), besides crassicauline A, forestine and yunaconitine. The structures of these alkaloides were determined on the basisi of spectral data and correlation with alkotoids of established structures. The structure and stereochemistry of acoforestine (10) was confirmed by an X-ray crystal structuer determination.

The structure and partial synthesis of delelatine, an alkaloid from Delphinium species

A new C-19-diterpenoid alkaloid designated as delelatine has been isolated from Delphinium elatum L. and D. tatsienense Franch. and its structure has been elucidated by spectroanalytical methods. Delelatine has been correlated with 14-acetyl-10-deoxydictyocarpine and synthesized from dictyocarpine, thus confirming its structure and stereochemistry.

The structure of tatsinine, a novel c19-diterpenoid alkaloid from delphinium tatsienense franch

A novel C19-diterpenoid alkaloid designated as tatsinine has been isolated from the roots of Delphinium tataienence and its structure (3) has been derived from 1H NMR and 13C NMR spectroscopic evidence.

Hetisine derivatives. Part 2. Novel rearrangement of 11-dehydrohetisine and 2,11-didehydrohetisine

Heating 11-dehydrohstisine (2) with sulfuric acid gave the rearragement produot 9. belongs to the orthorhombic space group P212121. 2,11-Didehydrohetisine (3) likewise afforded the rearranged triketone (10). The structure of the latter was confirmed by oxidation of 9 with pyridinium chlorochromate to 10.

Hetisine derivatives. Part 3. Rearrangement of 11-acetyl-2,13-didehydrohetisine and 13-dehydro-2,11-diacethylhetisine

Heating 11-Acetyl-2,13-didehydrohetisine (1) with apueous potassium carbonate in methanol afforded a rearrangement product, C20H25NO4,mp 313-315°C. The structure of this compound has been shown to be 4 by an X-ray crystallographic study. Mild treatment of 13-dehydro-2,11-diacetylhetisine (5) with base gave 2-acetyl-13-dehydro-11-epihetisine (7). Under refluxing conditions, 5 gave the rearrangement compound 8. The structure of 8 was assigned by chromium-trioxidepyridine oxidation to give 4.