Actinomycetes have an important role in the production of lead/seed compounds for pharmaceutical development, numerous useful bioactive compounds have been isolated from this extraordinary species. Approximately 40% of known bioactive compounds of microbial origin are derived from actinomycetes. In the course of our screening program to discover unique secondary metabolites, we previously reported several new metabolites from Streptomyces sp. (RK85-270 and RK88-1335). Here, we report that a continuation of our metabolite investigation of actinomycetes has resulted in the isolation of a new benadrostin derivative, RK-144171 (1), together with two known compounds, 3-indolylcarbonyl α-L-rhamnopyranoside (2) and 2-aminobenzoyl α-L-rhamnopyranoside (3) (Figure 1) from Streptomyces sp. RK88-1441. Details of the fermentation, isolation, structure elucidation and biological activities of the compounds are presented here.