Synthesis of indazolo[5,4-b][1,6]naphthyridine and indazolo[6,7-b][1,6]naphthyridine derivatives

Abstract

A simple method for the synthesis of the title compounds by an efficient in-situ reduction and cyclization reactions of aromatic aldehydes, tert-butyl 2,4-dioxopiperidine-1-carboxylate and 5-nitro-1H-indazole or 6-nitro-1H-indazole was developed.

Synthesis of 1,6‐Naphthyridine and Its Derivatives: A Systematic Review

“…Very recently, Chen et al (2019) adopted the same one-pot synthetic protocol to prepare indazolo [6,7-b] [1,6]naphthyridine (203) and indazolo [5,4-b][1,6]naphthyridine derivatives (205) from piperidin-2,4-dione (Scheme 51 and 52). [69] Here, the aromatic nitro compound is used instead of aromatic amine. The nitro group reduced to an amino group in situ using an excess amount (3 equivalents) of iron.…”

Experimental and theoretical study on the regioselective bis- or polyalkylation of 6-amino-2-mercapto-3H-pyrimidin-4-one using zeolite nano-gold catalyst and a quantum hybrid computational method

“…[11][12][13][14][15][16][17][18] As a result, the continued development of diverse pyrimidine derivative compounds remains in high demand. Some previously published protocols for the formation of analogues of the target moiety using acid, [19][20][21] basic, 22 metal catalysts, 23 or catalyst-free protocols under microwave 24 or thermal conditions. Unfortunately, all previous methods produce very low yields; thus, it was our goal to develop new conditions based on the use of a nanocatalyst in the hope of improving yields.…”