Integracides F and G: New tetracyclic triterpenoids from the endophytic fungus Fusarium sp.

Integracide K: A New Tetracyclic Triterpenoid fromDesmodium uncinatum(Jacq.) DC. (Fabaceae)

“…C-14)). These NMR data were quite similar to those of integracide-like compounds; 15,16,17 therefore the dienic system was positioned at C-14-C-15 and C-8-C-9 based on the literature. This was thereafter confirmed by HMBC correlations of CH 3 -19 (δ H 0.99) to C-14, C-12 (δ C 77.5), C-17 (δ C 49.1) and C-13 (δ C 46.8); H-12 (δ H 4.96) to C-14 and C-9; OH-11 (δ H 5.31) to C-9; CH 3 -18 (δ H 1.03) to C-9, C-1 (δ C 34.2) and C-10 (δ C 36.7).…”

“…Moreover, the presence of only one singlet signal at δ H 5.31 in the 1 H NMR spectrum and assigned to OH-11 group indicated the substitution of other two oxymethines located at C-3 and C-12. As such, the acetoxy group was located at C-12 based on the literature comparison of the NMR data of 1 with those of integracide A-J, 15,16,17 thus the sulphate group was located at C-3. The stereochemistry of the different chiral centers were established based on the comparison of their spectral data with those of reported compounds.…”

“…More precisely, the stereochemistry at C-11, C-12 and C-17 were confirmed based on the coupling constants observed for their corresponding proton atoms (Table 1) by comparing with those of reported integracides. 15,16,17 Thus the structure of compound 1 was elucidated as 4,4,24-trimethylcholesta-Δ 8,9;14,15;24,28 -trien-3β,11β,12α-triol-12-acetate,3-sulfate sodium salt.…”

“…Up to date, they have been reported only from fungi of Fusarium species such as Fusarium sporotrichioides 921, 18 Fusarium compactum 13 and Fusarium sp 14,15,16 and therefore seem to be the chemotaxonomic markers of these species. The present work is then the first report of an integracide-like compound from plants origin and so far from Desmodium species.…”

“…Integracides have been found to exhibit important inhibitory activity against the HIV-1 integrase 15,19 and to display potent cytotoxic and anti-leishmanial activities. 16,17 Therefore, various bioactivities of D. uncinatum used in Cameroonian folk medicine might not only be attributed to its isoflavonoid but also to integracide K.…”