3 rezultate
Four new Daphniphyllum alkaloids, daphnipaxianines A-D ( 1- 4), along with six known ones, have been isolated from the leaves and fruits of Daphniphyllum paxianum. Daphnipaxianines A and B ( 1, 2), a pair of epimers differing at C-10, are the first caliciphylline A type Daphniphyllum alkaloids with
Two new C-21 Daphniphyllum alkaloids, longeracinphyllins A (1) and B (2), have been isolated from the leaves of Daphniphyllum longeracemosum. Longeracinphyllin A (1) is a new daphnilongeranin B type alkaloid with a rearranged alpha,beta-unsaturated ketone group, and the structure is supported by
[reaction: see text] The ABC ring system of the natural product calyciphylline A has been synthesized. The key steps were a palladium-catalyzed intramolecular coupling of an amino-tethered vinyl bromide with a ketone using potassium phenoxide as the base to generate the C-ring and a