Aromadendrane, Maaliane

Plagiochila are divided into four chemotypes, an aromadendrane-maaliane-type (Type I), a 2,3-secoaromadendrane-type (Type II), a bibenzyl-type (Type III) and one in which the above constituents are absent (Type IV). Pedinophyllum truncatum is chemically quite similar to Type II of Plagiochila, since it elaborates 2,3-secoaromadendrane-type sesquiterpenes, plagiochiline C (48) and plagiochiline H (53) (2(5). Syzygiella liberata is chemically quite different from Plagiochila and Pedinophyllum species (25a). 

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. 

Partheniol, Sa-hydroxybicyclogermacrene (108) isolated from Partheniutn argentatum x Parthenium tomentosum, was cultured in the media of Mucor circinelloides ATCC 15242 to afford six metabolites, a humulane (109), three maaliane (110,112,113), an aromadendrane (111), and a tricylohumulane triol (114), the isomer of compound 111. Compounds 110, 111, and 114 were isolated as their acetates (Figure 20.36). 

Bicyclogermacrene (228) is widespread in the Hepaticae and an important biosynthetic intermediate for aromadendrane-, 2,3-secoaroma-dendrane- and maaliane-type sesquiterpenoids which are often coexist with (228) 21, 64). 

Some Porella species contain (—)-bicyclogermacrene (228), together with e r-gurjunenes (33, 35) and e r-cyclocolorenones (38, 39) (59). Compound (228) cooccurs together with aromadendranes (34, 38—42), 2,3-secoaromadendranes (45—54, 56—60) and maalianes (455, 458, 459) in most Plagiochila species 21, 64). Chiroptical properties of (228) are opposite to those found for the same compound in the peel oil of Citrus species 273, 274). 

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