Dereplicated novel actinomycetes from neglected habitats provide high quality biological material for screening programs designed to detect novel bioactive secondary metabolites. Neutrotolerant acidophilic streptomycetes which grow from pH 4.5 to 7.5, with an optimum between pH 5.0 and 5.5, were isolated from a hay meadow soil taken from Cockle Park Experimental Farm in Northumberland, UK. The isolates were grown as submerged cultures in complex media, and extracts from the culture filtrates and mycelia included in an HPLC-diode array screening program to detect novel secondary metabolites by means of an in-house HPLC-UV-Vis database. Strain BK 190 was of interest because of the presence of three prominent peaks in the HPLC profile of a culture filtrate extract, and was assigned to the genus Streptomyces by morphological and chemotaxonomic properties. Phylogenetic analyses showed it was most closely related to the type strain of Streptomyces sanglieri with a 16S rRNA similarity of 99.9%. The metabolite with retention time of 12.3 min was identified as elaiomycin (1), an azoxy antibiotic. Two further prominent peaks were elaiomycin B (2) and elaiomycin C (3), novel alkylhydrazides. A significant production of 1–3 was observed in oatmeal medium, reproducible in scale up to a 20-liter fermentor. Compounds 1–3 were isolated from the culture filtrate by Amberlite XAD-16 column, ethyl acetate extraction, and purified by diol-modified silica gel, Sephadex LH-20, and preparative reversed-phase HPLC. Pure 1 was a colorless oil, 2 and 3 white powders, with their physico–chemical properties summarized. Antimicrobial assays showed 2 and 3 were slightly active against Staphylococcus lentus (23% and 24% growth inhibition at 100 mM). Enzyme inhibition assays showed 2 and 3 inhibited acetylcholinesterase (IC50=1.0 mM and 2.0 mM, respectively) and phosphodiesterase PDE-4B2 (IC50=6.5 mM and 8.0 mM, respectively), while 1 was not active in both assays but showed moderate inhibition of HepG2 cell line (IC50=16.3 mM). As far as we know, elaiomycins B (2) and C (3) are the first natural occurring alkylhydrazides with therapeutic potential as shown by their inhibitory activity against clinically relevant enzymes.