Attempted synthesis of spongidines by a radical cascade terminating onto a pyridine ring.
Mn(III)-based oxidative free-radical cyclization of an unsaturated beta-keto ester containing a pyridine ring as radical trap has been studied. This intramolecular reaction of nucleophilic carbon-centered radicals with the pyridine ring leads to the stereospecific construction of a tetracyclic compound in which five chiral centers are created in one pot. This synthetic approach represents the first attempt to prepare the anti-inflammatory pyridinium alkaloids spongidine A, B, and D.
González
Miguel A
MA
Departamento de Química Orgánica, Universidad de Valencia, Dr. Moliner 50, 46100 Burjassot, Valencia, Spain. miguel.a.gonzalez@uv.es
Molina-Navarro
Sonia
S
D000470:Alkaloids / Q000138:chemical synthesis*; D003500:Cyclization; D008345:Manganese / Q000737:chemistry; D011725:Pyridines / Q000138:chemical synthesis*; D011726:Pyridinium Compounds / Q000138:chemical synthesis*
D000470:Alkaloids; D011725:Pyridines; D011726:Pyridinium Compounds; D008345:Manganese