Synthesis of New Pyrano‐fused Quinolines as Antibacterial and Antimicrobial Agents

Abstract

This manuscript describes a brief overview of latest research involving the use of pyrano‐fused quinolines as new antibacterial and antimicrobial agents. The synthesis begins with 4‐hydroxy quinolone‐2‐one 1a and 6‐fluoro‐4‐hydroxyquinolin‐2(1H)‐one 1b, which were obtained by condensation of aromatic amines with diethyl malonate. 9‐Fluoro‐6H‐pyrano[3,2‐c]quinoline‐2,5‐dione 3b and 6H‐pyrano[3,2‐c]quinoline‐2,5‐dione 3a were obtained by reaction with diethyl malonate in presence of ammonium acetate. These pyranoquinolones on refluxing in phosphorous oxychloride were converted to 5‐chloro‐2H‐pyrano[3,2‐c]quinolin‐2‐one 4a and 5‐chloro‐9‐fluoro‐2H‐pyrano[3,2‐c]quinolin‐2‐one 4b in good yields. The chloro functionality in compound 4a and 4b, which are reactive, can be replaced by various nucleophilic reagents such as amines and amino acids. The resulted amino pyrano[3,2‐c]quinolines showed moderate‐to‐excellent antibacterial and antimicrobial activity.

Synthesis of novel thiazol‐5‐ylpyrimidine derivatives and their antimicrobial evaluation

“…Inspired by the above‐mentioned potential biological activities of thiazolylpyrimidines, and our ongoing work aims for the synthesis of new molecules of pharmacological interest. [ 12–16 ] In this article, we disclosed an efficient method toward the synthesis of new series of thiazolylpyrimidine derivatives and were screened for their antimicrobial activity.…”

ZrOCl2·8H2O as an efficient and recyclable catalyst for the one‐pot multicomponent synthesis of novel [1,3]oxazino[5,6‐c]quinolin‐5‐one derivatives

“…[6][7][8][9][10][11][12][13][14][15][16][17] This wide range of biological properties has stimulated interest in the synthesis of quinolinone derivatives. [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] Recently, ZrOCl 2 ·8H 2 O has attracted much attention as catalysts in organic synthesis. Due to its easy availability, low costs, moisture stability, and low toxicity, ZrOCl 2 ·8H 2 O is effectively used as a green catalyst in organic reactions, such as synthesis of functionalized piperidine scaffolds, [34] synthesis of 5-amino-1-aryl-1H-tetrazoles, [35] synthesis of bis-β-amino ketones, [36] synthesis of homoallylic alcohols and amines, [37] synthesis of enaminones and enamino esters, [38] synthesis of N-substituted pyrroles, [39] synthesis of α-aminophosphonates, [40] synthesis of 2-substituted benzothiazoles, [41] synthesis of 3,4-dihydropyrimidin-2(1H)-ones, [42] synthesis of 1,8-dioxo-octahydroxanthene, [43] synthesis of imidazolines and bisimidazolines, [44] synthesis of 2-aryloxazolines and bisoxazolines, [45] synthesis of isobenzofuran-1(3H)-ones, [46] synthesis of β-acetamido ketones, …”

“…The quinolinone alkaloids isolated from the Rutaceae family of plants have been reported to exhibit a variety of biological properties . This wide range of biological properties has stimulated interest in the synthesis of quinolinone derivatives …”

Substituted quinolinones. 31. Some new pyrano[3,2‐c]quinoline‐3‐carboxamides and their antioxidant activity

“…[3,4] For instance, some pyrano [3,2-c]quinolines proved to be interesting antiviral agent against HIV, [5] potent topoisomerase TOP-IIβ and breast tumor inhibitors, [6] anticancer and anti-inflammatory agents, [7] and antimicrobial agents. [8] On the other hand, carboxamide derivatives exhibited a vital importance in medicinal applications. Thus, literature is full of examples for bioactive carboxamides especially as antioxidant agents.…”

“…In general, pyranoquinolines are mostly bioactive molecules, particularly pyrano[3,2‐ c ]quinolines revealed various potent medicinal properties . For instance, some pyrano[3,2‐ c ]quinolines proved to be interesting antiviral agent against HIV, potent topoisomerase TOP‐IIβ and breast tumor inhibitors, anticancer and anti‐inflammatory agents, and antimicrobial agents . On the other hand, carboxamide derivatives exhibited a vital importance in medicinal applications.…”