NoteAs part of our research program on the utilization of bioresouces in Thailand, we have been screening fungal extracts for in vitro assays inclusive of antimycobacterial and antiplasmodial activities. An extract from Aspergillus terreus BCC 4651 exhibited moderate activity against Mycobacterium tuberculosis H37Ra (minimum inhibitory concentration (MIC) 25 mg/ml) and the 1 H-NMR spectrum of the extract showed a unique profile, therefore, we selected the strain for large scale fermentation and chemical investigation. This study led to the isolation of two new butenolides, butyrolactones VI (1) and VII (2), together with the known compounds, butylolactone I (3), 1) butyrolactone II (4), 2) butyrolactone IV (5),3) butyrolactone V (6), 4) and aspernolide B (7). 5) A known diketopiperazine, bisdethiodi(methylthio)-acetylaranotin (8), [6][7][8] was also isolated as an antimycobacterial constituent of the culture extract. We report herein the structure elucidation of the new compounds and biological activities of isolated compounds. Results and DiscussionInitial study of the cultures grown in a common liquid medium, Czapek-Dox broth, under shaking resulted in the isolation of the known compounds 3-5, 7, and 8. Further studies revealed that butyrolactone derivatives were efficiently produced when the fungus BCC 4651 was fermented in yeast extract sucrose medium (YES; a sucrose-rich liquid medium) under static conditions. The culture provided with two new compounds 1 and 2 along with 3, 5, 6 and terrein, which is one of the commonly occurring Aspergillus toxins. 9)These compounds were isolated by column chromatography (Sephadex LH-20, silica gel, and reversed-phase HPLC), wherein fractions were analyzed by TLC and 1 H-NMR. Compounds 3-5, and 7 were identified on the basis of the MS and NMR data as butyrolactone I, 1,3) butyrolactone II, 12) Methylation of 6 (MeI, K 2 CO 3 , N,N-dimethylformamide (DMF)) gave the dimethylated derivative 9, which was subsequently converted to the (S)-and (R)-a-methoxy-a-(trifluoromethyl)phenylacetic acid (MTPA) ester derivatives 10a and 10b, respectively. The Dd-values (d S -d R ) of the Mosher esters unambiguously indicated the 8ЉS-configuration (Fig. 1).Butyrolactone VI (1) was isolated as a colorless solid. The molecular formula was determined to be C 24 H 26 O 9 by high resolution-electrospray ionization-mass spectra (HR-ESI-MS). The IR spectrum showed broad and intense absorption bands at n max 3442 (broad) and 1739 cm Ϫ1. The 1 H-and 13 C-NMR spectra were similar to those of other butyrolactone Butyrolactones from the Fungus Aspergillus terreus BCC 4651Rachada HARITAKUN, Pranee RACHTAWEE, Rungtiwa CHANTHAKET, Nattawut BOONYUEN, and Masahiko ISAKA* National Center for Genetic Engineering and Biotechnology; 113 Thailand Science Park, Phaholyothin Road, Klong Luang, Pathumthani 12120, Thailand. Received July 16, 2010; accepted August 3, 2010; published online August 6, 2010 Two new butenolides, butyrolactones VI (1) and VII (2), were isolated together with six known compounds, but...

A novel cyclodepsipeptide, cordycommunin (1), and two dihydroisocoumarins (2 and 3) were isolated from the insect pathogenic fungus Ophiocordyceps communis BCC 16475. The absolute configurations of the amino acid residues of 1 were addressed by application of Marfey's method. Cordycommunin (1) showed growth inhibition of Mycobacterium tuberculosis H37Ra with an MIC value of 15 microM. This compound also exhibited weak cytotoxicity to KB cells with an IC50 of 45 microM, while it was inactive against BC, NCI-H187, and Vero cell lines at a concentration of 88 microM (50 microg/mL).

The base-induced propargylation of the dye indigo results in the rapid and unprecedented one-pot synthesis of highly functionalized representatives of the pyrazino[1,2-a:4,3-a′]diindole, pyrido[1,2-a:3,4-b′]diindole and benzo [b]indolo [1,2-h]naphthyridine heterocyclic systems, with the last two reflecting the core skeleton of the anticancer/antiplasmodial marine natural products fascaplysin and homofascaplysins and a ring Bhomologue, respectively. The polycyclic compounds 6-8, whose structures were confirmed through singlecrystal X-ray crystallographic analysis, arise from sequential inter/intramolecular substitution-addition reactions, and in some cases, ring rearrangement reactions. Preliminary studies on controlling the reaction path selectivity, and the potential reaction mechanisms, are also described. Initial biological activity studies with these new heterocyclic derivatives indicated promising in vitro antiplasmodial activity as well as good anticancer activity. The chemistry described is new for the indigo moiety and cascade reactions from this readily available and cheap starting material should be more broadly applicable in the synthesis of additional new heterocyclic systems difficult to access by other means. Preliminary studies on controlling the reaction path selectivity, and the potential reaction mechanisms, are also described. Initial biological activity studies with these new heterocyclic derivatives indicated promising in vitro anti-plasmodial activity as well as good anti-cancer activity. The chemistry described is new for the indigo moiety and cascade reactions from this readily available and cheap starting material should be applicable more broadly in the synthesis of additional new heterocyclic systems difficult to access by other means.

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