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An Australian estuarine isolate of an Acremonium sp. (MST-MF588a) yielded the two known compounds 19- O-acetylchaetoglobosin D ( 1) and 19- O-acetylchaetoglobosin B ( 2), as the sole cytotoxic principles, along with the known aromatic metabolite RKB 3564S ( 3), and a novel family of lipodepsipeptides, acremolides A-D ( 4- 7). Structures were assigned to 4- 7 on the basis of detailed spectroscopic analysis and chemical derivatization and by application of a new C 3 Marfey's method for amino acid analysis.

Chemical analysis of an Australian marine-derived isolate of Penicillium bilaii, collected from the Huon estuary, Port Huon, Tasmania, yielded the known fungal aromatic polyketides citromycetin (1) and citromycin (2) together with two dihydro analogues, (-)-2,3-dihydrocitromycetin (3) and (-)-2,3-dihydrocitromycin (4). An Australian terrestrial isolate of Penicillium striatisporum collected near Shalvey, New South Wales, also yielded citromycetin (1), citromycin (2), and the new dihydro analogue (-)-2,3-dihydrocitromycetin (3), together with fulvic acid (5), anhydrofulvic acid (6), and a selection of new methoxylated analogues, 12-methoxycitromycetin (7), 12-methoxycitromycin (8), (-)-12-methoxy-2,3-dihydrocitromycetin (9), and 12-methoxyanhydrofulvic acid (10). P. bilaii also yielded the rare siderophore pistillarin (11), the known diketopiperazines cyclo-(L-Phe -L-Pro) (12), cyclo-(L-Pro-L-Tyr) (13), cyclo-(L-Pro-L-Val) (14), and cis-bis(methylthio)silvatin (15), and three new diketopiperazines, bilains A-C (16-18). The structures for the Penicillium metabolites 1- 18 were assigned by a combination of detailed spectroscopic analysis, including correlation with relevant literature data, chemical derivatization, degradation, and biosynthetic considerations. The citromycin polyketides 2 and 4 and the diketopiperazine 15 were weakly cytotoxic.