Antimalarial and antituberculosis substances from Streptomyces sp. BCC26924

Two new carbazomycin dimers (6 and 7) and 3-hydroxy-1,2-dimethyl-2,3-dihydro-1H-carbazol-4-one (9) together with six known compounds, carbazomycins A-D, cyclomarin C, and pimprinine have been isolated from Streptomyces sp. BCC26924. Carbazomycins B, C, and cyclomarin C exhibited antimalarial activity (against Plasmodium falciparum, K1 multi-drug resistant strain) with IC₅₀ in a range of 0.24-2.37 μg/mL. Cyclomarin C exhibited anti-TB activity with a minimum inhibitory concentration value of 0.10 μg/mL, while carbazomycin D, compound 7, and pimprinine displayed MIC values in a range of 12.5-25.0 μg/mL. In addition, compounds 2, 5, 6, and 7 showed weak cytotoxicity against cancerous (MCF-7, KB, NCI-H187) and non-cancerous (Vero) cells.     

Bis-spiro-azaphilones and azaphilones from the fungi Chaetomium cochliodes VTh01 and C. cochliodes CTh05

Four new dimeric spiro-azaplilones, cochliodones A-D (1-4), two new azaphliones, chaetoviridines E and F (5 and 6), a new epi-chaetoviridin A (7), together with five known compounds, chaetoviridin A (8), ergosterol (9), chaetochalasin A (10), 24(R)-5α,8α-epidioxyergosta-6-22-diene-3β-ol (11), and ergosterol-β-d-glucoside (12) were isolated from the fungi Chaetomium cochliodes VTh01 and C. cochliodes CTh05. Structures and stereochemistry of the atropisomers 1-3 were determined by single-crystal X-ray diffraction analysis. Compounds 5, 10, and 11 exhibited antimalarial activity against Plasmodium falciparum, while 3, 5, 6, 10, and 11 showed antimycobacterial activity against Mycobacterium tuberculosis. In addition, 5 and 6 also showed cytotoxicity against the KB, BC1, and NCI-H187 cell lines.