Three novel antitrypanosomal alkaloids, named spoxazomicins A-C, were isolated by silica gel column chromatography and HPLC from the culture broth of a new endophytic actinomycete species, Streptosporangium oxazolinicum K07-0460 T . The structures of the spoxazomicins were elucidated by NMR and X-ray crystal analyses and shown to be new types of pyochelin family antibiotic. Spoxazomicin A showed potent and selective antitrypanosomal activity with an IC 50 value of 0.11 lg ml À1 in vitro without cytotoxicity against MRC-5 cells (IC 50 ¼27.8 lg ml À1 ).

Five new anti-trypanosomal macrolides, actinoallolides A-E (1-5), were discovered from the cultured broth of Actinoallomurus fulvus MK10-036. The structures of the actinoallolides, including absolute stereochemistry, were elucidated by a combination of spectroscopic analyses and a series of chemical derivatization studies. Actinoallolide A showed the most potent and selective in vitro anti-trypanosomal activity without cytotoxicity. A new class of promising lead compounds was identified for the development of drugs for both sleeping sickness and Chagas disease.

Three new natural products, designated trehangelins A, B and C, were isolated by solvent extraction, silica gel and octadecylsilyl silica gel column chromatographies and subsequent preparative HPLC from the cultured broth of an endophytic actinomycete strain, Polymorphospora rubra K07-0510. The trehangelins consisted of a trehalose moiety and two angelic acid moieties. Trehangelins A (IC50 value, 0.1 mg ml(-1)) and C (IC50 value, 0.4 mg ml(-1)), with symmetric structures, showed potent inhibitory activity against hemolysis of red blood cells induced by light-activated pheophorbide a. However, trehangelin B, with an asymmetric structure, displayed only a slight inhibition (IC50 value, 1.0 mg ml(-1)).

A type B radical-SAM methylase homologue catalyses thiazoline C-methylation as the final step of watasemycin biosynthesis in Streptomyces venezuelae ATCC10712.