14-Membered cyclopeptides from Paliurus ramosissimus and P. hemsleyanus
Journal
Helvetica Chimica Acta
Journal Volume
86
Journal Issue
1
Pages
127-138
Date Issued
2003
Author(s)
Abstract
Abstract Six 14?membered cyclopeptide alkaloids, i.e. , ramosines A�VC, mucronine J, and lotusines A and D, were isolated from the roots of Paliurus ramosissimus , and an additional four, hemsines A�VD, from the roots of P. hemsleyanus. Among these, ramosines A�VC ( 1, 5 , and 6 , resp.) and hemsines A and B ( 7 and 8 , resp.) are new bases of the amphibine?B type, and hemsines C and D ( 9 and 10 , resp.) are new integerrine?type alkaloids. Additionally, ramosine C ( 6 ) represents the first 14?membered cyclopeptide alkaloid possessing a substitution (?OH) at C(13��). Their structural elucidations were based on spectral analysis and molecular?modeling studies. Pronounced solvent effects in the 1 H? and 13 C?NMR spectra of these two types of alkaloids were observed.
SDGs
Type
journal article