Synthesis of 1-Amino-3-oxo-2,7-naphthyridines via Smiles Rearrangement: A New Approach in the Field of Chemistry of Heterocyclic Compounds

Abstract

In this paper we describe an efficient method for the synthesis of new heterocyclic systems: furo[2,3-c]-2,7-naphthyridines 6, as well as a new method for the preparation of 1,3-diamino-2,7-naphthyridines 11. For the first time, a Smiles rearrangement was carried out in the 2,7-naphthyridine series, thus gaining the opportunity to synthesize 1-amino-3-oxo-2,7-naphthyridines 4, which are the starting compounds for obtaining furo[2,3-c]-2,7-naphthyridines. The cyclization of alkoxyacetamides 9 proceeds via two different processes: the expected formation of furo[2,3-c]-2,7-naphthyridines 10 and the ‘unexpected’ formation of 1,3-diamino-2,7-naphthyridines 11 (via a Smiles type rearrangement).

New Bicyclic Pyridine-Based Hybrids Linked to the 1,2,3-Triazole Unit: Synthesis via Click Reaction and Evaluation of Neurotropic Activity and Molecular Docking

“…We synthesized terminal alkines from the 3(6)-hydroxy derivatives of cyclopenta[ c ]pyridine 1a [ 25 ], 5,6,7,8-tetrahydroisoquinolines 1b – d [ 25 ], pyrano [3,4- c ]pyridines 1e – g [ 14 , 26 ], and 2,7-naphtyridines 1h , i [ 27 ] to obtain the aimed hybrids, the 1,2,3-triazoles. It should be mentioned that tautomerism is possible in compound 1 lactam-lactim (NH/OH) via proton-migration of a hydrogen atom between the two basic centers.…”

Synthesis of new pentaheterocyclic systems based on the triazolo[3,4-a]-2,7-naphthyridine core

“…13−15 2,7-Naphthyridines occupy a special place in our research in the field of the synthesis of fused heterocyclic systems -in our previous papers we have examined their reactivity with several amines and found a new unexpected rearrangement, 16,17 other chemical transformations leading to heterocyclizations 18,19 and an azide-tetrazole equilibrium. 20 Furthermore, in an our recent paper we successfully synthesized furo[2,3-c]-2,7naphthyridines 21 whose synthesis until recently failed. Some of these investigations revealed that bicyclic 1,3dihydroxy-2,7-naphthyridines showed antiarhythmic activity, 22 while tricyclic pyrazolo [3,4-c]-2,7naphthyridines 23 and triazolo [3,4-a]-, as well as some triazolo[5,1-a]-2,7-naphthyridines, 24 displayed high neurotropic activity.…”