Aromadendrane

These compounds range through monocyclic (with a bisabolane framework), bicyclic (with an eudesmane, amorphane, axane, guaiane, isodaucane, or gorgonane framework), tricyclic (with an aromadendrane, cubenane, maaliane, pupukeanane, or trachyopsane framework), and spiro[4,5]decane carbon skeletons. 

Alkenes of the aromadendrane series rearrange into tricyclic ring systems in fluorosulfuric acid828 [Eq. (5.301)]. The transformation of related compounds under similar conditions and calculations suggest the involvement of cation 212 as the key intermediate. 

Plagiochila acanthophylla subsp. japonica. Taylorione (294), a congener of myliol (295) in the liverwort Mylia taylorii, has been assigned the seco-aromadendrane structure (294) on the basis of chemical and spectroscopic evidence.127... 

Zhao WM, Ye QH, Dai JQ, Martin MT, Zhu JP (2003) a//o-Aromadendrane- and Picrotox-ane-type Sesquiterpenes from Dendrobium moniliforme. Planta Med 69 1136... 

A reinvestigation of the structures of the two marine metabolites lemnalactone and 7-epilemnalactone has resulted in definitive evidence in favour of (645) and (646) respectively. The three aromadendrane sesquiterpenoids (647)—(649)... 

A continuing investigation of the sesquiterpenoids from liverworts (Plagiochila species) has revealed the presence of more seco-aromadendrane compounds, namely plagiochilines A (652), B (653), C (654), D (655), E (656), and F (657). Plagiochilide (658) has been found in the Swiss species of P. asplenioides but not in the French version. The presumed precursor of these compounds, (-)-bicyclogermacrene (659), has also been identified in the extracts... 

C12 hydrocarbon (271)135 by a similar route but this compound is not identical to a tricyclic hydrocarbon isolated from East Indian sandalwood oil and reported to have this structure. (+)-Copacamphor (272) and (+)-copaborneol (273) have been isolated from Espeltiopsis guacharaca.136 The interesting sinularene derivative (274) and the acetoxycyclosinularane (275) have been isolated from the marine source, Clavularia inflata.137 These compounds, together with an aromadendrane derivative (see p. 181) are the first sesquiterpenoids from Octocorallia of the order Stolonifera. 

In addition to the two sinularane derivatives isolated from the marine source Clavularia inflata (see p. 114), the aromadendrane derivative (802) has also been identified in the related species Clavularia koellikeri.137 Another aromadendrane compound is the diol (803) obtained from the plant Senecio nemorensis.314 An X-ray analysis of nardosinone has confirmed its structure as (804).366 The soft coral Lemnalia africana is a rich source of sesquiterpenoids and recent investigations 383 e Trifilieff, Phytochemistry, 1980, 19, 2467. 

Stserk, D., Skole, B. and j0rgensen, F.S. (2004) Isolation of a library of aromadendranes from Landolphia didcis and its characterization using the VolSurfapproach./. Nat. Prod., 67, 799-805. 

Chemical and spectroscopic evidence has been provided to support the seco-aromadendrane structures assigned to plagiochilide (621) and plagiochiline A (622). ... 

Finally, Sm -induced reduction of strained alkyl halides has also resulted in cleavage of carbon-carbon bonds [102], The method has been utilized as the key step in the synthesis of dictamnol (Eq. 92). Further development of the method has led to an approach to the aromadendrane carbon skeleton [103] by a radical frag-mentation/3-exo cyclization process (Eq. 93). 

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