21738-16-9Relevant articles and documents
Probing Labdane-Related Diterpenoid Biosynthesis in the Fungal Genus Aspergillus
Xu, Meimei,Hillwig, Matthew L.,Tiernan, Mollie S.,Peters, Reuben J.
, p. 328 - 333 (2017/03/09)
While terpenoid production is generally associated with plants, a variety of fungi contain operons predicted to lead to such biosynthesis. Notably, fungi contain a number of cyclases characteristic of labdane-related diterpenoid metabolism, which have not been much explored. These also are often found near cytochrome P450 (CYP) mono-oxygenases that presumably further decorate the ensuing diterpene, suggesting that these fungi might produce more elaborate diterpenoids. To probe the functional diversity of such biosynthetic capacity, an investigation of the phylogenetically diverse cyclases and associated CYPs from the fungal genus Aspergillus was undertaken, revealing their ability to produce isopimaradiene-derived diterpenoids. Intriguingly, labdane-related diterpenoid biosynthetic genes are largely found in plant-associated fungi, hinting that these natural products may play a role in such interactions. Accordingly, it is hypothesized here that isopimarane production may assist the plant-saprophytic lifestyle of Aspergillus fungi.
Partial Synthesis of 9,10-Syn Diterpenes via Tosylhydrazone Reduction: (-)-(9β)-Pimara-7,15-diene and (-)-(9β)-Isopimaradiene
Chu, Min,Coates, Robert M.
, p. 4590 - 4597 (2007/10/02)
(9β)-Pimara-7,15-diene (3), a proposed intermediate in the biosynthesis of the momilactone phytoalexins (1 and 2) from rice, and its C-13 epimer, (9β)-isopimara-7,15-diene (4), were synthesized from methyl pimara- and isopimara-8,15-dien-18-oates (8b and 8a, respectively).Allylic oxidation of 8a and 8b as well as the derived diterpene hydrocarbons 15a and 15b with chromium trioxide-dipyridine complex afforded 8,15-dien-7-ones 9a, 9b, 16a, and 16b (35-54percent).Lithium-ammonia reduction of 9a, 16a, and 16b gave predominantly trans,anti,trans-isopimara- and -pimara-15-en-7-ones 10, 17a, and 17b.In contrast, catecholborane reduction of the tosylhydrazones of 9a and 9b provided methyl (9β)-isopimara- and (9β)-pimara-7,15-dien-20-oates (23a and 23b) having the 9,10-syn stereochemistry.The parent diterpenes, 3 and 4, were obtained by carboxyl-to-methyl conversions.In a collaborative investigation 3 was tentatively identified as one of five diterpene hydrocarbons produced upon incubation of (E,E,E)-geranylgeranyl pyrophosphate with a crude enzyme extract from UV-treated rice plants.