Figure - PMC

Skip to main content

View full-text article in PMC

. Author manuscript; available in PMC: 2012 Dec 22.

Published in final edited form as: J Med Chem. 2011 Nov 23;54(24):8471–8489. doi: 10.1021/jm201018g

Scheme 6 — Synthesis of pyrano(2,3b)pyridine analogues^a

R₁ = phenyl (20a), cyclohexyl (20b)

^a Reagents and Conditions: (a) (i) BuLi, -78 °C (ii). DMF, anh.ether, 31%; (b) R₁NH₂, ZnCl₂, NaCNBH₃, MeOH, 49%; (c) 3,4-diethoxybenzenesulfonyl chloride, Et₃N, DCM, r.t., 43 – 60%.