title: Microwave-promoted and Lewis acid catalysed synthesis of steroidal A- and D-ring fused 4,6-diarylpyridines.
abstract: The preparation of novel steroidal heterocycles containing 4,6-diaryl substituted pyridine moiety fused to the 2,3- and 16,17-positions of the steroid nucleus is described. The Michael reaction of steroidal ketones (1a, 1b and 1c) with in situ generated chalcones provided the intermediates 3,5-diaryl-1,5-dicarbonyl steroidal derivatives (4a-s). Subsequently, the intermediates 4a-s were converted to the pyridine derivatives (5a-s) by solid phase reaction with urea in presence of BF3.OEt2 as the catalyst under microwave irradiation. All the synthesized heterosteroids are new compounds and are currently being evaluated for their biological activities.
authors: Medicinal Chemistry Division, North-East Institute of Science and Technology, Jorhat, Assam 785006, India.
authors: Mandakini
authors: M
authors: Dutta
authors: Pallabi
authors: P
authors: Saikia
authors: Sanjib
authors: S
authors: Gogoi
authors: Romesh C
authors: RC
authors: Boruah
mesh_terms: D002384:Catalysis; D058116:Lewis Acids / Q000737:chemistry*; D008872:Microwaves; D008968:Molecular Conformation; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D013256:Steroids / Q000737:chemistry*
chemical_list: D058116:Lewis Acids; D011725:Pyridines; D013256:Steroids