NAPROC-13 is a freely accessible compound database containing over 24,000 NPs, with detailed information on their chemical structures and C NMR data. Notably, more than 4,000 compounds in NAPROC-13 have yet to be included in large NP databases, such as COCONUT, highlighting its unique contribution to the field. Our analysis shows that the chemical structures of NPs in NAPROC-13 exhibit similar physicochemical and constitutional properties to those in a broad and diverse set of NPs. However, they also contain distinct molecular fragments, scaffolds, and ring systems of pharmaceutical relevance, distinguishing them from other databases.