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3‐methyl‐4‐(hetero)arylmethylidene isoxazole‐5(4H)‐one derivatives (4a‐r) derivatives (4a‐r) were synthesized by the multi‐component reactions. The multi‐component reactions (MCRs) of hydroxylamine hydrochloride, ethyl acetoacetate and aromatic/ heteroaromatic aldehyde catalyzed by novel Glutamic acid (Glu) as a biodegradable and eco‐friendly organocatalyst in ethanol on oil bath stirring at 60 °C. The final product homogeneity was examined by various spectroscopic techniques. In this work prepared compounds 4 q and 4 r are novel derivatives. The molecular dynamics of total energy and energy gap was calculated using DFT/B3LYP/6–31G (dp) method. The selected derivatives (4 l–r) screened against in vitro MCF‐7 breast cancer cell line by MTT assay, derivatives 4 l and 4 o displayed very good activity with IC50 of 6.57±2.31, and 21.93±1.34 as compared to doxorubicin of IC50 (3.69±0.17). Molecular docking studies were performed to evaluate interaction of PDB id: 1 M17 with led molecules of MCF‐7. Later, 1 M17 and 4 l underwent 200 ns molecular dynamics and simulation within physiological conditions, the outcomes showed that during the simulation, the ligand stayed in the same form. Further, the selected derivatives drug like computed using swissADME, and derivatives 4 l–r obeyed rule of Lipinski's. Furthermore, selected derivatives tested for electrochemical behavior using cyclic voltammetry, and compound 4 l and 4 q showed strong oxidation and reduction potential, thus these derivatives can present better antioxidant properties. [ABSTRACT FROM AUTHOR]

Rapid and inexpensive one-pot multicomponent synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione through a condensation reaction of aryl aldehyde, malononitrile or ethyl cyanoacetate and phthalhydrazide catalyzed by water extract of papaya bark ash (WEPBA) solvent medium under microwave irradiation is described. The catalytic medium is used environmentally friendly, and provides several benefits of being simple, inexpensive, high yield, simple work-up and not required hazardous solvent for the reaction. Some of the selected derivatives were characterized by FT-IR, 1H-, and 13C-NMR, and mass spectrometry techniques. The oxidation-reduction properties of the synthesized compounds (4b, 4e, 4f, 4i, and 4k and 6f, 6g, 6h, 6i, and 6j) were studied using cyclic voltammetry (CV). The voltammetry peak current for the oxidation-reduction of the compounds examined at different scan rates. Further, some of the selected 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives were evaluated in vitro antioxidant activity using DPPH assay method. The result appears that, compounds 4b, 4e, 4i, 6f, 6g, and 6h possess significant antioxidant properties in comparison with the ascorbic acid reference. [ABSTRACT FROM AUTHOR]

In this work, we have described an efficient one-pot three-component preparation of 2-amino-4H-chromene by the reaction of aromatic aldehyde (1), malononitrile, or ethylcyanoacetate (2), and α or ꞵ-naphthol or resorcinol (3) in the presence of catalyst Water Extract of Orange Fruit Peel Ash agro-waste extracted solvent medium (4 mL) with few drops of ethanol as co-solvent accelerated by microwave irradiation. The reaction is optimized by various methods such as magnetic stirring, mechanochemical, ultrasound, and microwave irradiation, but the microwave irradiation in 180 W power gave excelled yield and faster rate product isolation (4–5 min). The method developed found eco-friendly, metal-free, chemical-less, and solvent-less, inexpensive, and facile approach for the synthesis of 2-amino-4H-chromene derivatives. The final product isolated recrystallized in ethanol, and characterized by FT-IR, 1H-, and 13C-NMR and LC-MS spectrometry techniques. Some of the selected chromene derivatives are subjected to antioxidant activity with concentration range 200–1,000 µg/µL by 2,2-diphenyl-1-picrylhydrazyl method. The derivatives 4a, 4 g, 4h, 6a, 6b, 6c, 8a, and 8f showed antioxidant activities and were comparable to standard ascorbic acid used. Further, studies on electrochemical behavior of selected chromene derivatives (4e, 4f, 4 g, 4i, 6c, 6f, 8d, and 8f) by cyclic voltammetry technique with 50 mVs−1, and revealed that, some of these molecules are good oxidation and reduction potential. [ABSTRACT FROM AUTHOR]

The present work describes one-pot synthesis of pyrano[2,3-d] pyrimidine derivatives using aromatic aldehyde, ethyl cyanoacetate and barbituric or thiobarbituric acid accelerated by microwave irradiation in the presence of agro-waste extract solvent medium with few drops of ethanol as a co-solvent presented. The reaction is optimized by various methods such as magnetic stirring, ultrasound, mechanochemical and microwave irradiation, but the microwave irradiation method excelled product formation faster rate with high yield and purity. The advantages of the present approach are the metal-free, chemical-less, and hazardous solvent-less employed and considered as an eco-friendly protocol for the synthesis of pyrano[2,3-d] pyrimidine derivatives developed. The final product isolated was recrystallized in ethanol and characterized by FT-IR, 1H-, 13C-NMR and LC-MS spectrometry. Further, some of the selected pyrano[2,3-d]pyrimidine derivatives (4a, 4b, 4d, 4f, 4m and 4o) are subjected to electrochemical behavior and anti-microbial activity studies. The anti-microbial activity tested derivatives showed comparable activities, and also electrochemical behavior of oxidation and reduction potentials observed by these compounds. [ABSTRACT FROM AUTHOR]

Environmentally benign, facile, and efficient one-pot three-component synthesis of pyrano[2,3-d]pyrimidine-2,4,7-trione derivatives by the reaction of aromatic aldehyde, barbituric acid and Meldrum's acid employing recently reported agro-waste catalyst WELFSA (Water Extract Lemon Fruit Shell Ash) from our group is described. The reaction found efficient in ultrasound at room temperature and took about 40 min for the reaction to complete. The catalyst has significant features in the present protocol gave high yield, simple reaction condition, non-hazardous, and not required chromatographic purification. The application of the ultrasound in organic synthesis is fulfilling some of the goals of the 'greener and sustainable chemistry', as it has some advantages over the traditional thermal methods in terms of reaction rates, yields and purity of the products. All the synthesized derivatives are characterized by FT-IR, 1H and 13C-NMR and mass spectrometry. [ABSTRACT FROM AUTHOR]

An efficient and rapid one-pot multicomponent synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-diones through condensation of aldehyde, malononitrile and phthalhydrazide catalyzed by agro-waste solvent catalyst-derived water extract of mango peel ash (WEMPA) under microwave irradiation is described. Further, the catalyst is prepared from agricultural waste and characterized for elemental composition by different techniques such as SEM-EDX, XRD and flame photometry. This green synthetic approach offers various advantages such as inexpensive, abundantly available source, shorter reaction time (6–8 min), good-to-excellent yield (83%–89%), simple workup and a sustainable alternative method to the existing protocols. All the synthesized compounds (4a–l) was confirmed by FT-IR, 1H-NMR, 13C-NMR and LC-MS. [ABSTRACT FROM AUTHOR]