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Milbemycin R, a novel spiro-heterocycle milbemycin, was obtained from the metabolites produced by the mutant strain S. bingchenggensis BCJ60B11. Its structure was determined by spectroscopic and sp...

Two new milbemycin derivatives, milbemycin M (1) and milbemycin N (2), were isolated from the culture of a genetically engineered strain Streptomyces bingchenggensis BCJ60. Their structures were elucidated through the interpretation of NMR and HR-ESI-MS spectroscopic data, as well as comparison with previous reports. The acaricidal and nematicidal activities of them against Tetranychus cinnabarinus and Bursaphelenchus xylophilus were tested. The results showed that compounds 1-2 possessed potent acaricidal and nematocidal activities.

Two new derivatives of cytotoxic substance BE-52211, designed as BE-52211D (1) and BE-52211E (2), were isolated from the fermentation broth of the strain Streptomyces sp. HS-NF-813. Their structure...

Two new naphthalenone derivatives, 5-hydroxy-4-oxo-2-(2-oxopropyl)-1,2,3,4-tetrahydronaphthalen-1-yl acetate (1) and 5-hydroxy-2-(2-hydroxypropyl)naphthalene-1,4-dione (2), together with tw...

A new spectinabilin derivative (1) was isolated from the fermentation broth of the ant-derived Streptomyces sp. 1H-GS5, and the structure was elucidated by extensive spectroscopic analysis. Compound 1 showed cytotoxicity against human tumor cell lines A549, HCT-116, and HepG2 with IC

Two new milbemycin derivatives, 27-methoxylmilbemycin α31 (1) and 27-oxomilbemycin α31 (2), were isolated from the genetically engineered strain Streptomyces bingchenggensis BCJ60. Their structures were determined by 1D NMR, 2D NMR and HR-ESI-MS spectral analysis, and comparison with previous reports. The acaricidal and nematocidal capacities of compounds 1 and 2 were evaluated against Tetranychus cinnabarinus and Bursaphelenchus xylophilus, respectively. The results showed that the two new macrocyclic lactones 1 and 2 possessed potent acaricidal and nematocidal activities.

Two new macrocyclic lactones, 4,25-diethyl-4,25-demethyl-milbemycin β3 (1) and 27-formaldehyde-milbemycin β14 (2), were isolated from a genetically engineered strain Streptomyces bingchenggensis BCJ60. Their structures were determined on the basis of spectroscopic analysis, including 1D and 2D NMR techniques as well as ESI-MS and comparison with data from the literature. The acaricidal and nematocidal capacities of compounds 1 and 2 were evaluated against Tetranychus cinnabarinus and Bursaphelenchus xylophilus, respectively. The results showed that the two new macrocyclic lactones 1 and 2 possessed potent acaricidal and nematocidal activities.

Four novel cyclopentenone derivatives (1-4), characterising a cyclopentenone ring conjugated with a 1,8-dioxadecalin, were isolated from rare actinobacterial strain Actinoalloteichus nanshanensis sp. nov. NEAU 119. The structures of these compounds were elucidated on the basis of extensive spectroscopic analysis. Bioassays indicated that compounds 1-4 showed low cytotoxicities against human leukaemia cell line K562 and human renal carcinoma cell line ACHN. To the best of our knowledge, this is the first example of isolation of C11 cyclopentenones from actinomycetes.

As a continuous work to find more epothilone congeners produced by the epothilones A and B producing Sorangium cellulosum strain So0157-2 in the large-scale fermentation (5000 L), we reinvestigated the chemical compositions of the fermentation broth. Consequently, two new epothilone variants (1-2) and one new natural epothilone derivative (3) were isolated from the fermentation broth. Their structures were established as 16-ethyl epothilone B (1), 6-desmethyl-16-hydroxymethyl epothilone C (2) and 20-ethyl epothilone A (3), respectively, by an extensive NMR analysis.