SYNTHESIS AND BIOLOGICAL EVALUATION OF 1H-PYRAZOLO [3,4-b] PYRIDINE-5 CARBOXYLIC ACIDS AGAINST VACCINIA VIRUS

Abstract

Several new 3-phenyl and 3-alky 1-l//-pyrazolo[3,4-Z>]pyridine derivatives (3a-e) were prepared and evaluated against Vaccinia virus on BSC-40 cells. The derivatives 3a, 3b and 3d showed an inhibitory activity above 90% at 30 μΜ, 40 μΜ and 50 μΜ concentrations.

An efficient Synthesis and Photophysical Properties of 1H-pyrazolo-[3,4-b]pyridine and pyrazolo[3,4-b][1,8]naphthyridines

“…For preparing pyrazolo [3,4-b]pyridine was used a known synthetic sequence, typically via reaction the 5-aminopyrazole with diethyl ethoxy methylenemalonate. This is general, easy and extensible technology for the construction of this heterocycles system [28][29][30][31][32]. A convenient route was successfully developed for the synthesis of novel synthon 4 with amino and aldehyde functionality adjacent to each other which is depicted in (Scheme 1).…”

Synthesis and antiviral activity of new 4-(phenylamino)/4-[(methylpyridin-2-yl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acids derivatives

“…A halogen in the C-4 position and an ester group in the C-5 position of 1H-pyrazolo[3,4-b]pyridine react readily with nucleophilic compounds to form a good precursor for the synthesis of these derivatives. Ethyl 4-chloro-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (1) was available in our laboratory and could be easily prepared from 5-aminopyrazoles through condensation with diethyl ethoxymethylenemalonate followed by chlorocyclization with phosphorus oxychloride (Hohn et al, 1971;Azevedo et al, 2002a;Azevedo et al, 2002b). Ethyl 4-chloro-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (1) on fusion with appropriate substituted anilines or aminopicolines gave the required new ethyl 4-(phenylamino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylates (2a-l) (52-82%) or new ethyl 4-[(methylpyridin-2-yl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylates (4a-c) (50-60%), respectively.…”

“…Recently our research group described the synthesis and antiviral activity of derivatives of the 1H-pyrazolo [3,4-b]pyridine and thieno [2,3-b]pyridine systems with promising results (Bernardino et al, 1996b;Azevedo et al, 2002a;Pinheiro et al, 2004;Bernardino et al, 2007).…”

Synthesis of Pyrido[2′,3′: 3,4]pyrazolo[1,5‐a]pyrimidine, Pyrido[2′,3′:3,4]pyrazolo[5,1‐c][1,2,4]triazine, and Pyrazolyl Oxadiazolylthieno[2,3‐b]pyridine Derivatives

“…Pyrazolopyridines are a very interesting class of heterocyclic compounds because of their significant and versatile biological and pharmacological activities such as antimalarial [1], antiproliferative [2], antimicrobial [3][4][5], cardiovascular [6][7][8], antiviral [9,10], and antileishmanial [11] activities. In addition, pyrazolotriazine were reported to have numerous biological activities [11,12].…”