Labdane-type diterpenoids

Suzuki M, Nakano S, Takahashi Y, Abe T, Masuda M, Takahashi H, Kobayashi K (2002) Brominated Labdane-Type Diterpenoids from an Okinawan Laurencia sp. J Nat Prod 65 801... 

Hashimoto. T K. Shiki, M. Tanaka, S. Takaoka, and Y. Asakawa, 1998b. Chemical conversion of labdane-type diterpenoid isolated from the liverwort Porella perrottetiana into ( ) amhrox. 9 ... 

Labdanum resin (from the Cistaceae family) contains diterpenoid compounds with a labdane-type structure, namely laurifolic, cistenolic and labdanolic acids [100 103]. 

Four bicyclic type diterpenoids have been reported from Salvia species labdanes, neo-clerodanes and clerodanes, seco-clerodanes, rearranged clerodanes. 

Whole plants of Scoparia dulcis collected in Paraguay were extracted with 70% EtOH at boiling temperature. The extract was partitioned between CHC13 and H2O and the CHC13 soluble part was further fractionated by combination of column chromatography on silica gel and HPLC method using reversed phase ODS column. As a result, three types of diterpenoids were isolated, i.e., labdane-type scoparic acids A (SA, 1), B (SB, 2), and C (SC, 3), scopadulan-type scopadulcic acids A (SDA, 4) and B (SDB, 5), and aphidicolan-type scopadulin (SD, 6). On the other hand, scopadiol... 

SDX, 7, labdane-type) and scopadulciol (SDC, 8, scopadulan-type) were newly isolated from Formosan collection of this plant. It is interesting that all isolated diterpenoids possess a benzoyl group in the molecule as shown in Fig. (1). In addition, quantitative HPLC analyses of diterpenoids in individual plants collected in Paraguay, Taiwan, China, Indonesia and Thailand revealed that there are three chemotypes in this plant as to the major component, i.e., SDB type, SA type and SDX type [21,22]. 

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]. 

The most widespread diterpenes reported in Baccharis genus are clerodanes, but labdane- and kaurane-type, and to a lesser extent beyerane-type diterpenoids have also been isolated. The investigation of ten Baccharis species afforded four new enr-labdane diterpenes from Baccharis oxydonta... 

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... 

C22H34O7, Mr 410.51, cryst., mp. 230-232 °C, [a]u -26.2 (CHCI3). Cardioactive diterpenoid (" labdane type) from the Indian medicinal plant Coleusforskolii (Lamiaceae). F. has a positive inotropic effect, it lowers blood pressure and has general vasodilatatory activity, especially on intravenous administration. The activity results from a direct stimulation of adenylate cyclase. F. is the archetype for all substances with this mechanism of action. In laboratory experiments it has been used successfully in therapy of congestive cardiomyopathy, glaucoma, or asthma. Several F. derivatives with improved solubility in water have been prepared. ... 

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. 

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. 

The diterpenoids are a large and ubiquitous family of isoprenoids derived from 2E,61% ] 0 -geranylgeranvl pyrophosphate. Of all the families of natural products, the diterpenoids have one of the widest ranges of biological activity. The clearest classification of the cyclic diterpenoids (abietane, labdane, clerodane,...) is based on biogenetic considerations. The variety of structural types found amongst the diterpenoids has led to their use as phytochemical markers. Indeed, many of the diterpenoids found in recent years have been isolated in the course of phytochemical surveys of the Compositae. 

Annomosin A (T43) is the first dimeric of the two ent-kaurane monomeric units isolated from the Annonaceae. In previous reports on Annonaceae plants, dimeric ent-kaurane diterpenoids have been reported composed of one e /-kaurane monomer and one labdane monomer, and were isolated only from Xylopia species [109-111], T43 consists of 19-al-ercr-kauran-17-oic acid and 16,17-dihydroxy-ewr- kauran-19-al. In the NOESY spectrum of T43, a correlation between H-12 and H-16 confirmed that the stereochemistry of H-16 was [3. The stereochemistry of OH-16 (3 was established by the NOE correlations between H-177H-13 and H-177H-14. On the other hand, the two aldehyde groups in C-19 and C-19 were confirmed unambiguously to be in an axial orientation from the NOEs between Me-18/H-3 3 and Me-18 /H-3 (3, respectively. Thus, the structure of T43 was determined to be 16(3-hydroxy- 19-al-e t-kauran -17-yl 16[3-hydro-19-al-e t-kauran-17-oate. This type of dimer... 

Compounds (308) to (311), which are considered to be breakdown flavors from labdane diterpenoids, were also exclusively found in Oriental-type tobaccos. Nor-ambreinolide (308), obtained for the first time from Manila cigar-type tobacco (284), its hemi-acetal and dehydro derivative (309), sclareol oxide (310), the unsaturated hydroxyketone (311) (75) and the drimane metabolite (238) (556) impart a pleasant cedar-like odor which is detectable to some extent in the cigarette package but is particularly detectable and pleasing in the mainstream and sidestream smokes when the cigarette is smoked (556). 

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). 

Diterpenoid distribution was contrasted to that of other terpenoids for the two genera, Baccharis and Helianthus. These two taxa were selected for a more detailed examination, because their chemistries represented the two major types of diterpene complements a bicyclic labdane/clerodane type Baccharis) and a polycyclic type Helianthus). 

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