Facile synthesis of new pyrazolo[4′,3′:5,6]pyrano[2,3-d]pyrimidin-5(1H)-ones via the tandem intramolecular Pinner–Dimroth rearrangement and their antibacterial evaluation

• Published in: Zeitschrift für Naturforschung. B, A journal of chemical sciences Vol. 74; no. 2; pp. 175 - 181
• Main Authors: Dorostkar-Ahmadi, Nadieh, Davoodnia, Abolghasem, Tavakoli-Hoseini, Niloofar, Behmadi, Hossein, Nakhaei-Moghaddam, Mahboobeh
• Format: Journal Article
• Language: English
• Published: BERLIN De Gruyter 25.02.2019; Walter De Gruyter
• Subjects: antibacterial; carboxylic acids; Chemistry; Chemistry, Inorganic & Nuclear; Chemistry, Organic; Physical Sciences; Pinner–Dimroth rearrangement; POCl; pyrazolo[4′,3′:5,6]pyrano[2,3; pyrimidine; Science & Technology; DESIGN; pyrazolo[4 ',3 ':5,6]pyrano[2,3-d] pyrimidine; PYRAZOLES; POCl3; antibacterial; MOLECULAR DOCKING; ANTITUMOR; IN-VITRO; ANTICANCER; carboxylic acids; BIOLOGICAL EVALUATION; BEARING; INHIBITORS; Pinner-Dimroth rearrangement; DERIVATIVES
• ISSN: 0932-0776; 1865-7117
• DOI: 10.1515/znb-2018-0166

Some new 7-alkyl-4,6-dihydropyrazolo[4′,3′:5,6]pyrano[2,3- ]pyrimidin-5(1 )-ones were prepared through heterocyclization of 6-amino-1,4-dihydropyrano[2,3- ]pyrazole-5-carbonitriles with aliphatic carboxylic acids in the presence of phosphoryl chloride under reflux in high yields. The suggested mechanism involves a tandem intramolecular Pinner–Dimroth rearrangement. The products were characterized on the basis of FT-IR, H NMR, and C NMR spectral and microanalytical data and evaluated for their antibacterial activity against Gram-positive bacteria ( and ) and Gram-negative bacteria ( and ) using the disk diffusion method.