Drimane sesquiterpenoids

Heterocycles in synthesis of drimane sesquiterpenoids from labdane diterpenoids 97IZV896. 

Avila, C., Cimino, G., Crispino, A., and Spinella, A., Drimane sesquiterpenoids in Mediterranean Dendrodoris nudibranchs anatomical distribution and biological role, Experientia, 47, 306, 1991. 

The structure of karatavic acid (50) has been revised and as such is the first example of a seco-drimane sesquiterpenoid. ... 

The diverse biological activity (e.g. insect antifeeding, plant growth regulation, molluscicidal) of a number of drimane sesquiterpenoids has stimulated considerable interest in their synthesis and the year under review has seen many new developments and improvements. Much of the synthetic work has centred around the key bicyclic diester (54) derived from 1-vinyl-2,6,6-trimethylcyclohexene and dimethyl acetylenedicarboxylate. In contrast to earlier results,34 Ley et al.8S... 

New drimane sesquiterpenoids include 6p-acetoxyisodrimenin (74), capsico-dendrin, a partially characterized tetramer of cinnamodial (63),45 albicanyl 3,4-dihydroxycinnamate (75), albicanyl 2,4-dihydroxycinnamate (76) (both liverwort constituents),48 and polyveoline (77), an indolosesquiterpenoid.47 Full details of the isolation and structural determination of pebrolide (78) and its congeners (79) and (80) have been published.48 The biosynthesis of pebrolide... 

In this review, the results of our investigations in the field of the synthesis of a number of optically-active, drimanic compounds from norlabdanic derivatives, the cleavage products of many available labdanoids, and also from a mixture of neoabienols (7) are summarized. The respective literature data are also discussed in the present article. A number of the prepared drimanes are naturally occurring biologically active substances. Others have been used as intermediates in the syntheses of important natural bioactive polyfunctional drimane sesquiterpenoids. Below the syntheses of the representatives of the drimane (1) group are described. 

We accomplished the drimenol (2) synthesis from the sclareol (3) [44] (Scheme 9). This was the first synthesis of a drimanic sesquiterpenoid... 

Albicanal (288) and (-)-drimenol (289) are simple drimane sesquiterpenoids isolated from the liverwort, Diplophyllum serrulatum, and many other liverworts and higher plants. The latter compound was incubated with M. plumbeus and R. arrhizus. The former microorganism converted 289 to 6,7a-epojQ - (290), 3p-hydroxy- (291), and 6a-drimenol (292) in the yields of 2%, 7%, and 50%, respectively. On the other hand, the latter species produced only 3p hydroxy derivative (291) in 60% yield (Aranda et al., 1992) (Figure 20.90). 

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