Mansonone isolation

Gerber has isolated (+ )-epicubenol (81) from a Streptomyces species. This compound is the enantiomer of that found in the essential oil of Cedrela toona Roxb. The syntheses of four naturally-occurring phenolic sesquiterpenoids obtained from the essential oil of elm wood have been reported, viz. (82 R = Me), (82 R = CHO), (83 R = Me), and (83 R = CHO). The known o-quinone, mansonone C (84), has also been isolated from elm wood. The structure (85) of sesquichamaenol, a minor component of the essential oil of Chamaecyparis forrnosensis, has been deduced on the basis of spectroscopic evidence and synthesis. Piers et al. have published complete details of their syntheses of a- and ) -cubebenes (86). 

Dumas et al.67 isolated Mansonone A (138), Mansonone C (139), Mansonone D (140), Mansonone E (121), Mansonone F (120) and Mansonone G (141) from the elm ulmus americana infected with... 

Benzenoid (-)-(75, 105)-calamenene is isolated from Ulmus thomasii (Uhnaceae), and (-l-)-3,8-calamenenediol from Heterotheca subaxillaris. The naphthalene sesquiterpene cadalene oeeurs in eonifers, for example in flie resin of fir Abies sibirica (Pinaceae). The wood of several trees contains 3-cadalenol. Cadalen-2,3-qutnone, also known as mansonone C, is a constituent of Mansonia altissima and Ulmus lactinata (Table 3). 

Ulmus species (Ulmaceae) (99, 100) may also be mentioned in this context. Some of these naphthalene derivatives cause staining of painted surfaces on the wood of slippery elm Ulmus rubra) (99). Related pigments of wood is mansonones -e.g. mansonone F (44) - that have been isolated from Mansonia altissima Chev. (Sterculiaceae) (81). The wood of this species is used for furnitures. Several allergic symptoms and heart troubles have been reported for workers handling this wood (81). 

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