Axisonitrile from Axinella cannabina

Axisonitrile-1 (1) and axisothiocyanate-1 (2) were the first pair of NC/NCS compounds isolated from Axinella cannabina, see Introduction [1]. That both compounds possessed a new skeleton was evident, when 1 was reduced (Li/EtNH2) to axane (6). Other transformations involving the exocyclic methylene which survived selective reduction (Na/NH3) of 1, coupled with evaluation of the lHNMR data, supported its gross structure. Confirmation of 2 was secured when 1 was heated with sulfur and the resultant purified product found to be identical to the natural product. 

Isocyanide-containing natural products are rare they have been reported only from cyanobacteria, Penicillium fungi, marine sponges, and nudibranchs. Sesquiterpenoid and diterpenoid isocyanides are found in a limited species of sponges and nudibranchs that prey on these sponges. Axisonitrile-1 (106) isolated from Axinella cannabina is the first isocyanide-containing marine natural product. ... 

Cafieri, F., Fattomsso, E., Magno, S., Santacroce, C., and Sica, D. (1973) Isolation and stmcture of axisonitrile and axisothiocyanate two unusual sesquiterpenoids from the marine sponge Axinella cannabina. Tetrahedron, 29, 4259-4262. 

Fattorusso and his co-workers 36, 77) obtained the first two from Axinella cannabina and proposed the names of axisonitrile-1 (47) and axisonitrile-2 (48), respectively. 

The second isonitrile component, axisonitrile-2, of Axinella cannabina is reported by Fattorusso and his co-workers (77) to be (48) based on the aromadendrane skeleton. They have shown that the hydrocarbon formed from axisonitrile-2 on Birch reduction is identical with the hydrogenation product of aromadendrene, whose stereochemistry shown in (57) has... 

Cafieri, F., E. Fattorusso, S. Magno, C. Santacroce, and D. Sica Isolation and Structure of Axisonitrile-1 and Axisothiocyanate-1, two unusual Sesquiterpenoids from the marine sponge Axinella cannabina. Tetrahedron 29, 4259 (1973). 

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