PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 6030305-9 1967 Stepwise degradation of the acetic acid by standard procedures gives two samples of carbon dioxide, which correspond to C-2 and C-3 of the nicotinic acid. Niacin 139-153 complement C3 Homo sapiens 128-131