Oleane triterpene

Friedo-oleane triterpenes with a hemiacetal 24-hydroxy-3-oxo grouping are exclusive to the Celastraceae and several have been isolated from South American species. It has been proposed that these compounds may be intermediates in the biogenetic pathway to the Celastraceae triterpene quin ones. 

Dammar is produced by trees belonging to the Dipterocarpaceae family. It is mainly composed of triterpenoids, but it also contains a polymeric fraction based on polycadinene, a polysesquiterpene [37,38]. The main components of the triterpene fraction are compounds with a dammarane type skeleton and oleane/ursane type molecules [39,40]. 

By using betulin as substrate, some mechanistic studies were performed and it was demonstrated that these reactions are catalyzed by Brpnsted acid species generated in situ from the hydrolysis of Bi(0Tf)3-.vH20. This process was also applied to other terpenic compounds. The sesquiterpene ( )-caryophyllene oxide originated clov-2-en-9a-ol by a cariophyllene-clovane rearrangement (Scheme 41) whereas 3-oxo- l 8a-olean-28- l 3(3-olide was obtained from oleanonic acid (Scheme 42). With this triterpene derivative, only 28,13(3-lactonization occurred, with inversion of the configuration of the stereocenter at C18 [133],... 

Maniladiol (= Olean-12- ene-3P,16P-diol) (triterpene) Helianthus annuus (Asteraceae) CHY (-100 pM) [105]... 

The fatty/waxy products contained the lipophilic substances, including fatty oils, waxes, resins and colorants. Valuable pharmacological effects were proved for some minor constituents of these products (e.g. triterpenes, diterpenes, sterols and carotenoids). Thin layer chromatography and on-line UV-VIS spectroscopy were used for the quick identification and quantity determination of these compounds using authentic samples as standards. The SFE method proved favorable in terras of both extraction yield and speed of carotenoids. The CO2 extracts of the lavandin, clary sage and thyme have been enriched in triterpenic compounds (a-es P-amyrin, oleanic acid, ursolic acid, etc.) and phytosterols. Both free and esterified triterpenoids were present in the extracts of the different samples. Furthermore camosol and other diterpenes were detected in the SFE extract of Lamiaceae plants. The fatty acid composition was only slightly different for extracts obtained by SFE and conventional hexane extraction. 

Ardisicrenoside C (= 3(3,16a,28-Trihydroxy-olean-12-en-30-oic acid 3-0-Rha-Glc-[Glc] -Ara-30- 0-Glc (triterpene glycoside) Ardisia crenata (Myrsinaceae) [root] cAMP PDE (46)... 

The two main triterpene dialcohols in olive oil are erythrodiol (homo-olestranol, 5a-olean-12-ene-3 3,28-diol) and uvaol (A-12-ursen-3(>,28-diol) (Figure 9.7). 

Figure 8. Transposed Friedo-olene Type Skeleton Triterpenes [58] 3-oxo-25(9->8) abeo-friedoolean-(4)(23)-en-24->l-olida (119) y 3-oxo-25(9->8) abeo- riedoolean-(4)(23)-en-24-al (120) transposed friedo-oleane type skeletons isolated from Schaefferia cuneifolia...

Recently, the ethanol extract of dried root bark of T. wilfordii yielded another triterpene with friedo-oleane skeleton, isolated by Yang et. al. [32]. The H and 13C-NMR, HMBC, HMQC and NOESY data, and their comparison with those from triptocaline-A, allowed to establish the structure of the new compound as 6a-hydroxytriptocalline-A (7), Fig. (4). 

Oleanes comform the other group of triterpenes found in Celastraceae that- with friedelanes- are the most common skeletons isolated from the family. 

Also from T. wilfordii [33] others six triterpenes have been isolated. 2a,3 p-dyhydroxy-olean-12-ene-22,29-lactone (20) had an olefinic proton signal, three hydroxyl methine protons and seven tertiary methyl signals based on its H NMR spectrum. Examination of its 13C NMR data showed... 

Compound (21) showed a C NMR spectrum very similar to that of (20), except for the A-ring. Thus, it was also a 22,29-lactone-oleane-12-ene-type triterpene. According to the degrees of insaturation and the data provided by the HMBC experiment, the A-ring showed to be disunited between C-2 and C-3. Thus, (21) was elucidated to be 2,3-seco-22,29-lactone-oleane-12-ene-2,3-dioic acid 3-methyl ester, Fig. (14). 

Compounds (22), (23) and (24) were also 12-ene oleane-type triterpenes based on comparison of their 13C NMR spectra with that of (20). They differed with regard to the substituted functions at C-3. According to its 2D NMR spectroscopic data, (22) was 28-hydroxy-3-oxo-olean-12-en-29-oic acid. In the same way, the coupling constant of H-3 in (23) and (24) and analysis of the NOESY spectrum suggested that (23) and (24) were 3p,28-dihydroxy-olean-12-en-29-oic acid and 3a,28-dihydroxy-olean-12-en-29-oic acid respectively, Fig. (15). 

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