## 2 Triterpenoids
### 8,9-ene-triterpenoids
#### 2.2.7 Rearranged Novel Triterpenoids
Except for the above structures, it is noted that two triterpenoid lactones, ganodermalactones G and F (**472** and **473**) containing a spiroketal-lactone and bicyclo-spiroketal-lactone skeletons, were first isolated from the EtOAc extract of the cultured biomass of _Ganoderma sp_. KM01 and a possible biogenetic pathway for ganodermalactone G (**472**) and ganodermalactone F (**473**) were proposed (Figure 24) [210]. Further bioactivity assay showed: (1) Colossolactone V (**461**), colossolactone VI (**462**) and colossolactone E (**467**) exhibited inhibitory activity against HIV-1 protease with IC\({}_{50}\) values of 9.0, \(>\)100 and 8.0 \(\upmu\)g/mL, respectively, El Dine 2008b [312]. (2) Colossolactone C (**464**), colossolactones D (**466**), E (**467**), F (**468**) and colossolactone G (**471**) showed moderate cytotoxicity against L-929, K-562 and HeLa cells with IC\({}_{50}\) values ranging from 15  
Figure 23: Chemical structures of polyoxygenated lanostane triterpenoids: austrolactone (**459**) and australic acid (**460**). to 35 \(\upmu\)g/mL. However, they showed no antimicrobial activity against a spectrum of bacteria and fungi [207]. (3) Colossolactone H (**470**) as a new triterpene dilatactone produces more cytotoxic than colossolactone G (**471**) and shows cytotoxicity against lung, breast, and colon cancers and hepatoma cells, suggesting that it may be a beneficial adjuvant for the therapy involved in treating a wide range of cancers [59]. Compounds **468** and 23-hydroxycolossolactone E (**469**) were active against _P. syringae_ and _B. subtilis_[211]. Ganodermalactone F (**473**) [313]) and colossolactone E (**467**) showed antimalarial activity against _Plasmodium falciparum_ with IC\({}_{50}\) values of 10.0 and 10.0 \(\upmu\)M, respectively [210]. Chemical structures of different rearranged novel triterpenoids are shown in Figure 25.  
Figure 25: Chemical structures of several rearranged novel triterpenoids (**461–473**). Fornicatins A (**474**), B (**475**) and D-F (**476**-**478**) (Figure 26) were 3_A-seco_-tinortriterpenoids. Among them, fornicatins A and B (**474** and **475**) were first isolated from the fruiting bodies of _G. fornicatutum_ and tested for their inhibitory effects on rabbit platelet aggregation induced through either a platelet activating factor (PAF), adenosine diphos-phate (ADP), or arachidonic acid (AA) [314]. These compounds were also obtained from _G. cochlear_. Fornicatins A (**474**), D (**476**) and F (**478**) displayed in vitro hepatotoxicity activities by lowering the ALT and AST levels in HepG2 cells treated with H\({}_{2}\)O\({}_{2}\)[57]. Cochlates A and B (**479** and **480**) (Figure 27) with a 3,4-seco-9,10-seco-9,19-cyclo skeleton were a pair of isomers and were isolated from _G. cochlear_[57]. The only difference between **479** and **480** was the position of the ester. Considering the wide distribution of fornicatin B (**475**) in _G. cochlear_, cochlates A and B (**479** and **480**) could be derived from a modification of **475**. Therefore, a possible biosynthetic route of **479** and **480** was proposed, as shown in Figure 28[57]. Figure 28: The biosynthetic route of cochlates A (**479**) and B (**480**). Figure 27: Chemical structures of cochlate A (**479**) and cochlate B (**480**) as rearranged novel triterpenoids. According to the literature, the unprecedented four-membered framework of methyl ganosinensate A (**481**), ganosinensic acid A (**482**) and ganosinensic acid B (**483**) (Figure 29) was produced by a bond across C-1 to C-11 due to the radical reaction (Figure 30) [315]. These three new triterpenenoids were isolated from _G. sinensis_ and showed weak cytotoxicity against HL-60, SMMC-7721, A-549, MCF-7 and SW480 cell lines [315]. Three new nortriterpenes, ganoboninketals A-C (**484-486**) (Figure 31) featuring rearranged 3,4-_seco-27_-norlanostane skeletons and complex polycyclic systems were isolated from _G. bontinense_[52].