The invention provides substituted pyrrolo[1, 2-a]pyrimidines and related organic compounds, compositions containing such compounds, medical kits, and methods for using such compounds and compositions to treat medical disorders, e.g., Gaucher disease, Parkinson' s disease, Lewy body disease, dementia, or multiple system atrophy, in a patient. Exemplary substituted pyrrolo[1, 2-a]pyrimidines compounds described herein include substituted 2, 4-dimethyl-N-phenylpyrrolo[1, 2-a]pyrimidine-8-carboxamide compounds and variants thereof.