Synthesis of [1,2,5]selenadiazolo[3,4-f]quinolone derivatives by the Gould-Jacobs reaction of 5-amino-2,1,3-benzoselenadiazole

Abstract

Dedicated to Prof. Paweł Kafarski in honor of his scientific achievements within his career AbstractThe Gould-Jacobs reaction of 5-amino-2,1,3-benzoselenadiazole afforded solely angularly annulated 8-substituted 9-oxo-6,9-dihydro-[1,2,5]selenadiazolo[3,4-f]quinoline derivatives. In the course of thermal cyclization no linear products were observed. Nucleophilic vinylic substitution of activated enolethers with 5-amino-2,1,3-benzoselenadiazole was also studied.

Synthesis of 9-ethyl[1,2,5]selenadiazolo[3,4-h]quinolones by the application of modified Gould-Jacobs reaction to N-ethyl-2,1,3-benzoselenadiazol-4-amine

“…The starting compounds 1, 4, 7 and 21 were prepared according to procedures described in our previous papers. 7,8 The alkoxymethylidene derivatives 17a and 17b are commercially available . NaH (60 % suspension in mineral oil, 23 mg, 0.57 mmol) was added to a stirred suspension of selenadiazoloquinolone 1 (100 mg, 0.4 mmol) in dry DMF (2 mL) under the Ar atmosphere at room temperature and stirring was continued for 1 hour.…”

“…3,4 The presence of selenium in the structure of 4-quinolones can bring new characteristics, and plenty of selenaheterocyclic compounds showed positive biological impact. 5,6 In our previous research, 7-substituted selenadiazolo [3,4-h]quinolones and 8-substituted selenadiazolo [3,4-f]quinolones (R 7 , R 8 = H, CN, COCH 3 , COOMe, COOEt, COOH) were successfully synthetized by the GouldJacobs reaction 7,8 and their biological/photobiological activity was investigated together with their EPR spectroscopy. [9][10][11][12] Antimicrobial activity of 7-substituted selenadiazolo [3,4-Analogously, treatment of selenadiazoloquinolone 4 with EtI in the presence of K 2 CO 3 afforded a mixture of N-and O-ethylated products 5 and 6 in almost the same ratio as in the previous case.…”

New syntheses of 5,6- and 7,8-diaminoquinolines

“…Moreover, in the case of 3-nitro- and 3-chloroaniline, the Skraup reaction affords a mixture of 5- and 7-substituted quinolines, making their separation necessary. To avoid these drawbacks, the readily available angularly annelated selenadiazoloquinolones, prepared as detailed in our previous papers [ 13 – 14 ], were employed as the precursors of o -diaminoquinoline derivatives. The preparation and application of 7,8-diaminoquinoline hydrochloride in the synthesis of nitrogen heterocycles is discussed in datail.…”

Stable Radical Trianions from Reversibly Formed Sigma-Dimers of Selenadiazoloquinolones Studied by In Situ EPR/UV–vis Spectroelectrochemistry and Quantum Chemical Calculations

“…7−10 Our effort to prepare selenaheterocyclic compounds resulted in a successful utilization of the Gould−Jacobs reaction in the efficient synthesis of selenadiazoloquinolones. 11,12 The presence of selenium in a molecule can provide new attributes, and some of the synthesized selenaheterocyclic compounds demonstrated biological impact, as previously reviewed. 13−15 Comprehensive studies of potential biological/photobiological activities of selenadiazoloquinolones, as well as their capacity to promote the formation of photoinduced reactive oxygen species were recently performed in our group.…”

“…The four-generation family of antibacterial agents with 4-oxoquinoline structure represents an important tool in the treatment of bacterial infections. − In particular, the latest fourth-generation fluoroquinolones reveal a broad-spectrum bactericidal activity against gram-positive and gram-negative pathogens coupled to improved pharmacokinetic properties. , However, because of the increased bacterial resistance to quinolone antibiotics, there is a permanent interest in the synthesis of novel 4-oxoquinoline derivatives possessing an extended number of biological activities. , Recently, quinolone-annulated derivatives with an additional heterocyclic ring containing nitrogen, sulfur, or selenium atoms were synthesized, and their biological effects were examined. − Our effort to prepare selenaheterocyclic compounds resulted in a successful utilization of the Gould–Jacobs reaction in the efficient synthesis of selenadiazoloquinolones. , The presence of selenium in a molecule can provide new attributes, and some of the synthesized selenaheterocyclic compounds demonstrated biological impact, as previously reviewed. − Comprehensive studies of potential biological/photobiological activities of selenadiazoloquinolones, as well as their capacity to promote the formation of photoinduced reactive oxygen species were recently performed in our group. ,, The ability of selenadiazoloquinolones to generate paramagnetic intermediates and singlet oxygen upon photoexcitation was studied by means of EPR spectroscopy using the spin-trapping technique and oxidation of sterically hindered amines. Ultraviolet A photoexcitation of the selenadiazoloquinolones in dimethylsulfoxide (DMSO) or acetonitrile resulted in the activation of molecular oxygen generating the superoxide radical anion and singlet oxygen.…”