Efficient Preparation of 2-Substituted Pyridazino[4,3-h]psoralen Derivatives

Abstract

An efficient synthesis of 2-chloro-6-methoxypyridazino[4,3-h]psoralen was achieved by Diels-Alder reaction of 3,6-dichloro-1,2,4,5-tetrazine and 8-methoxy-psoralen (8-MOP) in a one-pot procedure. The convenient transformation of this intermediate into the 2-triflate derivative allowed efficient palladium-catalyzed reduction, methoxycarbonylation , and Sonogashira cross-coupling reactions at C₂.

Diels-Alder - catalysis - DNA - palladium - polycycles

References

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Compounds 5, 6, 7, 8, 9 and 10 gave satisfactory analytical and spectroscopic data.