Two novel reddish-orange alkaloids, mycoleptodiscin A (1) and mycoleptodiscin B (2), were isolated from liquid cultures of the endophytic fungus Mycoleptodiscus sp. that had been isolated from Desmotes incomparabilis in Panama. Elucidation of their structures was accomplished using 1D and 2D NMR spectroscopy in combination with IR spectroscopic and MS data. These compounds are indoleterpenes with a new skeleton uncommon in nature. Mycoleptodiscin B (2) was active in inhibiting the growth of cancer cell lines with IC 50 values in the range 0.60−0.78 μM.