RESUMO
An operationally simple, one-pot multicomponent reaction has been developed for the assembly of pyrido[2,3-d]pyrimidine and pyrazolo[3,4-b]pyridine derivatives (4a-4am) in excellent yields (92-94%) with high purity. The reactions were easy to perform simply by mixing of electron-rich amino heterocycles (including aminouracils and aminopyrazoles), aldehyde, and acyl acetonitrile in the presence of [Et3NH][HSO4] under solvent-free conditions. The remarkable feature of the present approach is that the ionic liquid possesses dual solvent-catalytic engineering capability. Results of this study revealed that 1 mmol of the ionic liquid catalyst under solvent-free conditions at 60 °C is the best reaction parameter for the construction of fused pyridine and pyrimidine derivatives in excellent yields. The present methodology showed good results under gram-scale conditions, thereby indicating its applicability in industrial as well as academic settings in the near future.
RESUMO
An economic, sustainable, and straightforward environmentally friendly synthesis of highly diversified polyfunctional dihydrothiophenes is successfully achieved via diisopropyl ethyl ammonium acetate as a room-temperature ionic liquid. Multicomponent synthesis contains domino processes; the benefit of this present protocol is highlighted by its readily available starting materials, superior functional group tolerance, purity of synthesized compounds was checked by high-performance liquid chromatography results in up to 99.7% purity for the synthesized compounds, reaction mass efficiency, effective mass yield, and excellent atom economy. In addition, a series of 2-(N-carbamoyl acetamide)-substituted 2,3-dihydrothiophene analogs were synthesized, and selected samples were chosen for testing their in vitro antibacterial and antifungal activities. Furthermore, a molecular docking study against sterol 14α-demethylase could provide valuable insight into the mechanism of antifungal action providing an opportunity for structure-based lead optimization.
RESUMO
The diisopropyl ethyl ammonium acetate (DIPEAc)-promoted Biginelli protocol has been developed for the first time by a successive one-pot three-component reaction of aldehydes, ethylcyanoacetate/ethyl acetoacetate, and thiourea/urea to afford pharmacologically promising 1,2,3,4-tetrahydropyrimidines in high yields at room temperature. The key benefits of the present scheme are the capability to allow a variability of functional groups, short reaction times, easy workup, high yields, recyclability of the catalyst, and solvent-free conditions, thus providing economic and environmental advantages. In addition, a series of 4-oxo-6-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitriles analogues were synthesized and selected for their in vitro antifungal and antibacterial activities.
RESUMO
In this paper we examine the issues pertaining to development of a low-cost telerehabilitation framework for upper-limb dysfunction, that is suitable for deployment in patients' homes. We use the example of a Virtual Driving Environment (VDE) to present the overall architecture and discuss issues of: (i) quantitative data-acquisition using commercial-off-the-shelf gaming devices; (ii) model-based parametric data transmission/playback; and (iii) parametric biomechanical identification and data reduction; to support individualization within the telerehabilitation regimen.