Twelve new compounds, variecolorins A-L ( 1- 12), together with eleven known analogues ( 13- 23) were isolated from the broth of a halotolerant fungus, Aspergillus variecolor. The structures of compounds 1- 12 were determined by chemical and spectroscopic methods. Compounds 1- 11, 13- 15, and 20- 23 exhibited weak radical scavenging activity against DPPH, with IC 50 values from 43 to 103 microM. The new compounds 1- 12 all were essentially nontoxic against the P388, HL-60, BEL-7402, and A-549 cell lines with IC 50 values from 70 to 260 microM.

Three new diketopiperazine alkaloids, 6-methoxyspirotryprostatin B (1), 18-oxotryprostatin A (2), and 14-hydroxyterezine D (3), with an oxaspiro[4.4]lactam moiety, 14-norpseurotin A (4), and the 29-nordammarane triterpenoid 6beta,16beta-diacetoxy-25-hydroxy-3,7-dioxy-29-nordammara-1,17(20)-dien-21-oic acid (5), as well as 12 known compounds (6- 17), were isolated from the ethyl acetate extract of a marine-derived fungal strain, Aspergillus sydowi PFW1-13. The structures of compounds 1- 5 were elucidated by comprehensive spectroscopic analysis. Compounds 1- 3 exhibit weak cytotoxicity against A-549 cells, with IC 50 values of 8.29, 1.28, and 7.31 microM, respectively. Compound 1 also shows slight cytotoxicity against HL-60 cells, with an IC 50 value of 9.71 microM. Compounds 4 and 5 display significant antimicrobial activities against Escherichia coli, Bacillus subtilis, and Micrococcus lysoleikticus with MICs of 3.74, 14.97, and 7.49 microM and 10.65, 5.33, and 10.65 microM, respectively.

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Six new indole alkaloids including five new glyantrypine derivatives (1, 2a, 2b, 3, 4) and a new pyrazinoquinazoline derivative (5), together with eight known alkaloids (6-13), were isolated from the culture of the mangrove-derived fungus Cladosporium sp. PJX-41. Their structures were elucidated primarily by spectroscopic and physical data. The absolute configurations of compounds 1-9 were established on the basis of CD, NOESY data, and single-crystal X-ray diffraction analysis. Compounds 2b, 5, 7-9, and 11 exhibited significant activities against influenza virus A (H1N1), with IC50 values of 82-89 μM.