Total syntheses of the benzodiazepine alkaloids circumdatin F and circumdatin C.
Total syntheses of circumdatin F and circumdatin C, which both possess a 3H-quinazolin-4-one as well as a 1,4-benzodiazepin-5-one moiety, are described. A tripeptide derivative was synthesized as a key intermediate and dehydrated to a benzoxazine by reaction with triphenylphosphine, iodine, and a tertiary amine. The natural products were attained via rearrangements to an amidine intermediate, deprotection with 45% HBr in acetic acid, and cyclization on silica gel.
Witt
A
A
Unit for Organic Chemistry, Department of Biosciences, Karolinska Institute and Södertörn University College, Novum Research Park, SE-141 57 Huddinge, Sweden.
Bergman
J
J
D000470:Alkaloids / Q000138:chemical synthesis*; D001235:Aspergillus ochraceus / Q000737:chemistry; D001569:Benzodiazepines / Q000138:chemical synthesis*; D011480:Protease Inhibitors / Q000138:chemical synthesis*
D000470:Alkaloids; D011480:Protease Inhibitors; C438460:circumdatin C; C428194:circumdatin F; D001569:Benzodiazepines