85559-67-7Relevant academic research and scientific papers
Chiroptical Properties of the Protoverbine Class of Macrocyclic Spermine Alkaloids
Drandarov, Konstantin,Guggisberg, Armin,Linden, Anthony,Hesse, Manfred
, p. 1773 - 1791 (2007/10/03)
The chiroptical properties (circular dichroism, CD) of the 17-membered macrocyclic spermine lactam alkaloids (-)-protoverbine (16), its N,N′-methylene-bridged natural analogue (+)-protomethine (17), their natural derivatives (-)-verbacine (1), (-)-verballocine (2), (-)-verbascenine (3), (-)-verballoscenine (4), (+)-verbamethine (5), (+)-incasine C (6), (+)-verdoline (incasine B′, 30), (+)-incasine B (31), and some of their isosteric analogues were studied. By chemical and chiroptical correlation, it was confirmed that an amidically bonded (S)-β-phenyl-β-alanine fragment forms the chiral moiety in all of these natural compounds. The signs of the registered Cotton effects (CEs) are interpreted in terms of the Smith's quadrant rule for the 1Lb CEs of chiral α-substituted benzylamines and the Ogura's sign rule for n→π* CEs of lactams. Some of the conclusions regarding configuration are supported for the rigid bicyclic compound (-)-(9S)-9-phenyl-1,6-diazabicyclo[4.3.1]decan-7-one (15) by the X-ray crystal structure of the racemate.
Verbascenin, ein macrocyclisches Spermin-Alkaloid aus Verbascum
Seifert, Karlheinz,Johne, Siegfried,Hesse, Manfred
, p. 2540 - 2547 (2007/10/02)
The new spermine alkaloid verbascenine (1) has been isolated from extracts of the aerial parts of Verbascum phoeniceum L. and V. nigrum L.The structure of the alkaloid was elucidated by chemical degradation and by a study of the spectral properties of the
