The mycelial cake was extracted with acetone, and filtered. The filtrate was concentrated to give aqueous solution, which was extracted with chloroform. Organic layer was concentrated to yield an oily material, followed by purification on silica gel column chromatography to give crude UK-1 and UK-2. Finally, the recrystallization of each fractions from MeOH, afforded UK-1 and UK-2. UK-1 (1), a novel metabolite, demonstrated potent cytotoxic activity against B16, Hela and P388 cells, and UK-2, novel complex of antibiotics, exhibited strong antifungal activity. The molecular formula of UK-1 was determined as C_<22>H_<14>N_2O_5 by HREI-MS data (M^+: m/z 386.0913). Methylation of UK-1 by CH_3I and anhydrous K_2CO_3 in dry acetone gave monomethyl ether derivative, Me-UK-1 (2). Alkaline hydrolysis of UK-1 afforded carboxylic acid derivative, DeMe-UK-1 (3). Partial structures, A, B, and C were elucidated by COSY, and COLOC experiments. Based on these results, the structure of UK-1 was deduced to be formula 1, the novel benzoxazole dimmer derivative. UK-2, novel metabolite containing complex of antibiotics, exhibited strong antifungal activity was purified by reverse phase HPLC, to give UK-2A, B, C and D. The molecular formulas C_<26>H_<31>N_2O_9 (M^+: 515.2030) for UK-2A, C_<27>H_<30>N_2O_9 (M^++H: 527.2030) for UK-2B and C_<27>H_<32>N_2O_9 (Mt^+: 528.2114) for UK-2C and D were established by EIRFAB-MS and HREI-MS, respectively. Partial structures, (3-hydroxy-4-methoxypicolinyl)-serine (E), 2-benzyl-3,4-dihydroxypentanoic acid (F), and carboxylic acids (G) were indicated by COSY, and COLOC spectra. Chemical degradation of UK-2 by 5% NaOH solution afforded (3-hydroxy-4-methoxypicolinyl)-serine (4) and mixture ester of 2-benzyl-3-hydroxy-4-methyl-4-butanolide (6). Based on these results, the structures of UK-2A, B, C and D were elucidated as nine membered dilactone derivatives, distinguished by acyl group at C-3. From NMR and mass spectral data, the structures of UK-2A, B, C and D were established as isobutyrate, tiglate, isovalerate, and 2-methylbutyrate of nine membered dilactone skeletone, respectively. Based on the result of synthesis of hydrolysis products (6 and 8), the absolute configuration of UK-2 was identified as shown in formula UK-2 [2(R), 3(R), 4(S)].
