Pimarane-type diterpenoids

Generally, terpenoids have been believed to be biosynthesized via acetate-mevalonate pathway. Aphidicolin, a tetracyclic diterpenoid isolated from moulds, Cephalosporium aphidicola [47] and Nigrospora sphaerica [48], was also proved to be biosynthesized from mevanonic acid [49]. In this pathway, isopentenyl pyrophosphate (IPP), geranylgeranyl diphosphate (GGPP), labdane-type and pimarane-type diterpenoids were proposed to be intermediate precursors of aphidicolin [50]. 

Labdane and pimarane type diterpenoids are rather rare in Turkish Sahna species, and only a few of these compounds have been obtained. Sclareol and manool were isolated from S. scktred. Manool was also obtained from S.limbaia, while manoyl oxide was reported from S. camlidissiiru/ together with 11 P-hydroxymanoyl oxide and 8,13-di-e/rr-manoyl oxide . Although these two compounds were... 

Colophony is a complex mixture of resin acids (about 90%) and neutral substances, i.e. diterpene alcohols, aldehydes and hydrocarbons (about 10%). Its composition varies with the species from which it is obtained and also depends on the recovery processes and storage conditions. The acids are diterpenoid acids, of which the abietane- and pimarane-type structures are the most abundant (Fig. 1). Tail-oil rosin contains less abietane-type acids and more dehydroabietic acid than gum rosin does. This is due to oxidation-... 

The distribution of diterpenoids in the Hepaticae is restricted to certain genera. Representatives of two new types, the sacculatanes and verruco-sanes, as well as labdane-, pimarane- and kaurane-type diterpenoids have been encountered so far in the Hepaticae, although there are many minor unidentified diterpenoids in each species. 

The labdane-, pimarane- and kaurane-type diterpenoids so far isolated from the Hepaticae belong to the -series while higher plants produce both normal and /-labdanes, pimaranes and kauranes. 

From the comparative study of the diterpenoids, the genus Jungermannia is divided into two types a labdane-pimarane-type (erect stem type, such as Jungermannia rosulans, J. thermarum and J. torticalyx) and a kaurane-type [creeping stem type, J. infusca and J. tristis ( = /. atrovirens)] (228). 

We ve classified more than 550 diteipenoids (listed in Table 3 whith corresponding sources) from all the reported Salvia species which we ve divided into 2 categories. The first one contains the monocyclic and bicyclic diterpenoids including labdanes and clerodanes and related diterpenes. The second category concerns tricyclic and tetracyclic diterpenes including pimaranes and abietanes and related diterpenes. The clerodane type diterpenes are mainly represented by american species while abietane type are found in european and asian species. 

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