We have constructed an isolated natural compound library designed to facilitate extensive biological screenings. The library consists of over 1000 isolates, including over 140 'JBIR compounds' that were discovered in our laboratory. To enrich this library, we recently initiated a screening program for rare microbial products using the advanced compound-identification system designated as 'MBJ's special selection'. As a result, our program yielded novel compounds named 'MBJ compounds', such as a cytotoxic hydroxamate MBJ-0003 from Micromonospora sp. 29867; cytotoxic eremophilane derivatives MBJ-0009 and MBJ-0010 from Nectria sp. f26111; MBJ-0011, MBJ-0012 and MBJ-0013 from Apiognomonia sp. f24023; cytotoxic chaetoglobosin derivatives MBJ-0038, MBJ-0039 and MBJ-0040 from Chaetomium sp. f24230; bicyclic depsipeptides MBJ-0086 and MBJ-0087 from Sphaerisporangium sp. 33226; and aziridine-containing peptide MBJ-0035 from Streptosporangium sp. 32552. Further screening for novel compounds led to the identification of MBJ-0110 (1) from the culture of Penicillium sp. f25267. Herein we report the fermentation, isolation, structure elucidation and preliminary biological activity data.