Camosic acid synthesis

ABSTRACT This article reviews the literature published dealing with the synthesis of some bioactive diterpenes. It describes the biological activity and synthesis of only four diterpenes pisiferic acid, camosic acid, triptolide and miltirone. This review excludes the discussions of Taxodione, a bioactive diterpene, because it has already been reviewed [85], The utility of several reagents in the total synthesis of terpenoid compounds has been documented. It can be observed that several routes have been developed for the synthesis of a single diterpene. 

The first total synthesis of camosic acid (89). was accomplished by Meyer et al. [28], Meyer developed two different routes for the synthesis of camosic acid. This is exhibited in Figs. (12) and (13). 

Meyer also developed another route for the synthesis of camosic acid (89) and this is described in Fig. (13). 

The synthesis of camosic acid dimethyl ether by Meyer et al records some interesting aspects. Michael addition of ketoaldehyde with two new reagents proved very useful in the synthesis of tricyclic ketone. In the second approach a very easy method has been described for the introduction of hydroxyl group at C-l 1 position. 

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