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Microwave-Assisted Preparation of 1-Aryl-1H-pyrazole-5-amines
Published on: June 23, 2019
Regiospecific one-pot synthesis of pyrimido[4,5-d]pyrimidine derivatives in the solid state under microwave
Dipak Prajapati1, Mukut Gohain, Ashim J Thakur
1Department of Medicinal Chemistry, Regional Research Laboratory, Jorhat 785 006, Assam, India. dr_dprajapati@rediffmail.com
Abstract:
Electron rich 6-[(dimethylamino)methylene]amino uracil 1, undergoes [4+2] cycloaddition reactions with various in situ generated glyoxylate imine and imine oxides 6 to provide novel pyrimido[4,5-d]pyrimidine derivatives of biological significance, after elimination of dimethylamine from the (1:1) cycloadducts and oxidative aromatisation. This procedure provides a convenient method for the direct synthesis of pyrimido[4,5-d]pyrimidines in excellent yields when carried out in the solid state and under microwave irradiations.
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