Friedelane

Morikawa, T. Kishi, A. Pongpiriyadacha, Y. Matsuda, H. Yoshikawa, M. Structures of new friedelane-type triterpenes and eudesmane-type sesquiterpene and aldose reductase inhibitors from Salacia chinensis. J. Nat. Prod. 2003, 66, 1191-1196. 

Kishi A, Morikawa T, Matsuda H, Yoshikawa M. (2003) Structures of new friedelane- and norfriedelane-type triterpenes and pPolyacylated endes-mane-type sesquiterpene from Salacia chinensis Linn. S. prinoides DC., Hippocrateaceae) and radical scavenging activities of principal constituents. Chem Pharm Bull 51 1051-1055. 

XIV, R = CH3 and C2H5, respectively, Fig. 10b), whereas the sediment contains additional friedelin, i-friedelanol and ursolic acid. Furthermore, the friedelin photoproducts, i.e. dihydroputranjivic acid (3,4-r c<7-friedelan-3-oic acid, XV) and 4a- and 4P-3-norfriedelane (XVI) are dominant sedimentary components. Thus, characterizing photoproducts from terpenoids may provide additional biomarker tracer compounds for environmental studies. 

Methyl trisnorshionanoate (126) has been synthesized from friedelan-19a-ol (127) via the ring-contracted intermediate (128) and the trisnor-ketone (129). Irradiation of (129) in methanol afforded the desired ester (126). An investigation of the effect of solvent on the backbone rearrangement of 3/8,4/3-epoxyshionane (130) by boron trifluoride etherate has shown that nucleophilic solvents tend to interrupt the rearrangement at an early stage (see Vol. 6, p. 130). 

Full papers have appeared on the friedelanes from Hydnocarpus octandra and Trichadenia zeylanica, the mechanism of the photochemical reaction of friedelin with acetone, and the rearrangement of 3/8,4/3-epoxyfriedelane (195) to... 

Some oleanane type triterpenoids with highly oxygenated were isolated form Barringtonia racemosa as shown in Fig 6. Six friedelane type triterpenoids were isolated from bark of Hibiscus tiliaceus collected from Flainan province as shown in Figure 7. 

Figure 7. Structures of friedelane type triterpenoids from Hibiscus tiliaceus...

The conversion of shionone into dihydrobaccharis oxide (80) has been reported.59 3/3,4/3-Epoxyshionane (81), on treatment with boron trifluoride etherate, afforded (80) and bacchar-12-en-3j8-ol (82). The high-resolution mass spectral fragmentation patterns of a number of shionane and friedelane derivatives have been examined.60... 

Simplification and clarification of spectra often yield a good deal of information. An elegant example of the use of shift reagents is shown in Fig. 10.13. This figure shows the NMR spectrum of friedelan-3//J-ol with and without added shift reagent Eu(thd)3. 

Fig. 10.13. NMR spectrum of friedelan-3/l-ol (10mg, 0.24 x 10-4 mol in 0.4 ml of CDCI3) (a) normal spectrum at 100 MHz, (b) partial 220-MHz spectrum of solution of friedelan-3/l-ol containing one mol equivalent of...

Friedelin (friedelane triterpene) Ceratopetalum petalum (Cunoniaceae), Quercus suber (Fagaceae) [cork], Viola odorata (Violaceae), lichens PKA... 

Kotalagenin 16-acetate (friedelane triterpene) Salacia oblonga (Gelastraceae) [root] AR (rat lens) (-100)... 

The full paper on the partial synthesis of methyl trisnorshionanoate (115) from friedelan-19a-ol has appeared (see Vol. 8, p. 168). 

The structure of salaspermic acid (143), a new friedelane hemiacetal from the stem and root wood of Salacia macrosperma, was confirmed by X-ray analysis of the rearrangement product (144). Six new oxygenated friedelanes have been isolated from Kokoona zeylanica. Kokoonol (145), kokoonidiol (146), and kokoononol (147) provide rare examples of C-27 oxygenation and zeylanol (148), zeylanonol U49), and zeylandiol (150) are 6/3-hydroxy-derivatives. ... 

The two different C31H54 pentacycles (m/e 426), one observed in BB2 extract and one in POWl extract had no M-29, M-43 or M-57 fragments. The m/e 205 was small, ruling out structures like lupan-3-one (16). Other differences also eliminate friedelan-3-one and oleanan-3-one type of structure ( 16). 

The friedelanes (146)—(148) have been isolated from Catha cassinoides (Celas-traceae). The structure and stereochemistry of (147) were proved unambiguously by X-ray analysis of the corresponding acetate.102 Structure (147) had previously been assigned to octandronal (see Vol. 4, p. 214), a compound with different... 

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