Synthesis and Spectroscopic Comparison of the Eight Methyl-2,3’-bipyridyls and Identification of a Hoplonemertine Alkaloid as 3-Methyl-2,3’-bipyridyl
作者:William R. Kem、H. Martin Garraffo、Thomas F. Spande、John W. Daly、Ferenc Sóti、James Rocca
DOI:10.3987/com-08-s(d)80
日期:——
The pyridyl ring is frequently found in natural products and drugs. While bipyridyls have served as useful scaffolds for development of industrial and pesticidal chemicals, their biological properties are still not well understood. Only 2,3'-bipyridyl, of the six isomeric bipyridyls, has been reported as a natural product in tobacco plants and in a hoplonemertine marine worm, Amphiporus angulatus (Aa), which uses its pyridyl alkaloid-rich venom to paralyze its crustacean prey and chemically defend itself against predators. Here we report for the first time the synthesis and spectroscopic properties of all eight possible methyl 2,3'-bipyridyl isomers and use this data to identify a trace alkaloidal constituent of Aa as 3-methyl-2,3'-bipyridyl. This is only the second reported instance of a methyl-bipyridyl being found as a natural product, the first being the tobacco alkaloid 5-methyl-2,3'-bipyridyl.