Nocardia is the causative microorganism of a human infection called nocardiosis. It is also known to produce a variety of compounds with antitumor,1,2 antimicrobial3,4 and immunosuppressive activity.5,6 To take up iron, which is an essential element for all organisms, into cells under iron-deficient conditions, microorganisms produce iron chelators, namely, siderophores. Five types of siderophores have been isolated: hydroxamates, catecholates, salicylates, nitrosophenols and carboxylates.7 Some siderophores, such as brasilibactin A,8 asterobactin,9 nocobactin NA10 and nocardamine,11 are produced by Nocardia spp. In the course of our screening program for biologically active compounds of microbial origin, we isolated a novel heterobactin12 analog, JBIR-16 (1), containing hydroxamate and catecholate, from the culture broth of Nocardia tenerifensis NBRC 101015 (Figure 1). In this paper, we report the production, isolation, structural determination, and briefly the biological activity of 1.