High-resolution tandem mass spectrometry (HR-MS<sup>2</sup>)-based metabolomic studies of <i>Amycolatopsis saalfeldensis</i>, isolated from the "Saalfelder Feengrotten" caves in Germany, led to the isolation of three ribosomally synthesized and post-translationally modified type II thiopeptides, saalfelduracin B-D (<b>1</b>-<b>3</b>) and the known saalfelduracin A (<b>4</b>). The structures of all four compounds were determined by comparative two-dimensional NMR analysis and high-resolution tandem mass spectrometry.