Page 1. Tetrahedron Letters,Vo1.27,No.28,pp 3271-3274,1986 0040-4039/86 $3.00 + .OO Printed in Great Britain Pergamon Journals Ltd. ... References 1) a) MXBoudakin, "Heterocyclic Compounds, Pyridine and Its Derivatives," ed by RAAbramovitch, Vol. ...