Alkaloids from cigar

Abstract

Phytochemical investigation on cigar tobacco led to identification of 16 alkaloids including two undescribed nicotine dimeric analogs, cigatobines A-B (1-2), as well as new natural products pyridylnicotine (3), cis-5'-(2-oxopropyl)-nicotine (8) 4-(formamido)-1-(3-pyridyl)-1-butanone (14), 5,6-dihydropyridin-2(1H)-one (15). Some chemical mechanisms including Minisci reaction and nucleophilic addition reaction were involved in formation of dimeric nicotine and its derivatives. Molecular docking on this type alkaloids with the α7-nAChR receptor disclosed five active compounds with binding affinity scores of -8.077 of 2, -7.805 of nicotine, -7.804 of 8, -5.788 of 1, -5.707 of 3, -7.452 of epibatidine. This study disclosed the difference in alkaloids between cigar and tobacco.

Keywords: Cigar tobacco; alkaloids; cigatobines A-B; nicotine dimer; α7-nAChR receptor.