Ultrasound-promoted synthesis of bi-, tri- and tetrapodal polyhydroquinolines, 1,4-dihydropyridines and the corresponding pyridines

Abstract

Bi-, tri-and tetrapodal polyhydroquinolines and 1,4-dihydropyridines were synthesised by the reaction of various alkylating agents with polyhydroquinolines and 1,4-dihydropyridines under sonication conditions.These were in turn converted to the corresponding pyridines also using sonication. Sonication produced higher yields in a faster reaction time. All the synthesized compounds were characterized using spectral data.

Use of Ultrasound in the Synthesis of Heterocycles of Medicinal Interest

“…Synthesis of pyrimidine/pyridine derivatives has been reported by numerous methods [83][84][85][86][87][88][89] previously. The first group of pyrimidine derivatives (92) was prepared in aqueous NaOH solution, by the addition of aromatic aldehyde (90) to acetyl acetone (89) and thiourea (91) (Scheme 23(a)). The first group of pyrimidine derivatives (92) was prepared in aqueous NaOH solution, by the addition of aromatic aldehyde (90) to acetyl acetone (89) and thiourea (91) (Scheme 23(a)).…”

“…Balaji et al [90] synthesized bi-(98), tri- (99), and tetrapodal polyhydroquinolines (100) and 1,4-dihydropyridines (101) by the reaction of various alkylating agents with polyhydroquinolines and 1,4-dihydropyridines under ultrasound irradiation. The products were further converted to the corresponding pyridines also using ultrasonic energy, producing higher yields in shorter reaction times (Scheme 24).…”

Evaluation of the antioxidant activities of fatty polyhydroquinolines synthesized by Hantzsch multicomponent reactions

“…[7][8][9] In recent years, much consideration has been given to the synthesis of the PHQ derivatives because of their pharmacological signicance, which makes them potential targets for a number of biological applications. [10][11][12][13] However, the important results around these small biologically active molecules have inspired further research to identify new, similar substances with diverse structures and to better understand the relationship between the variation in the chemical structure and biological activity.…”

Microwave-assisted clean synthesis of xanthenes and chromenes in [bmim][PF6] and their antioxidant studies

“…With all of this in mind, and as part of our ongoing research devoted to the development of novel synthetic methods in heterocyclic chemistry [26][27][28][29][30], here we describe the microwave-assisted synthesis of xanthene and chromene derivatives by the reactions of arylaldehydes, 2-naphthol or 4-hydroxycoumarin and 1,3-cyclodiones in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF 6 ]).…”