(S)-5-Bromocoerulescine, is a derivative of Coerulescine, which is an oxindole that can be found in the plant Horsfieldia superba, and it has analgesic effects.
Jossang, A. et al.: J. Org. Chem. 56 (23): 6527–6530; Lakshmaiah, G. et al.: J. Org. Chem.64 (5): 1699–1704;