Six new (1-6) and nine known (7-15) staurosporine derivatives were isolated from the rice solid fermentation of the marine-derived Streptomyces sp. NB-A13. The structures of the new staurosporine derivatives were established by extensive spectroscopic data interpretation. The absolute configurations of 1 and 2 were assigned by quantum chemical calculations of the electronic circular dichroism (ECD) spectra. All of these compounds were screened for their cytotoxic activities against PC-3 and SW-620 cell lines. Compound 7 exhibited stronger inhibitory activity against SW-620 cell lines than the positive control staurosporine (25.10鈥痭M), with IC(50) values of 9.99鈥痭M. Moreover, compounds 1-5, 8-13 and 15 also showed significant cytotoxicities with IC(50) values ranging from 0.02 to 16.60鈥痬uM, while 6 exhibited no cytotoxic potency. Additionally, compounds 1-7 were also tested for enzyme inhibition activities of Protein kinase C theta (PKC-theta), and showed activity with IC(50) values ranging from 0.06 to 9.43鈥痬uM except for compound 6, which has no inhibition activity. CI - Copyright (c) 2018 Elsevier Inc. All rights reserved.