C-lactam derivatives of oleanolic acid. The synthesis of C-lactam by Beckmann rearrangement of C-oxime

Nat Prod Commun. 2011 Dec;6(12):1813-6.

Abstract

Oleanolic acid, one of the most known triterpenes, was subjected to different chemical transformations within C-3 beta-hydroxyl group, a double bond between C-12 and C-13, and a carboxyl function at C-17 in order to obtain new derivatives. The key compound consists of four six-membered rings (A, B, D, E) and one enlarged ring (C ring) containing a nitrogen atom and a carbonyl function - lactam. This type of derivative can be obtained by Beckmann rearrangement of the appropriate oxime. The lactam can be transformed into thiolactam with the use of Lavesson's reagent. The method is also presented for new derivatives synthesis, as well as their structure elucidation by spectroscopic means.

MeSH terms

  • Lactams / chemical synthesis*
  • Oleanolic Acid / analogs & derivatives*
  • Oximes / chemistry*

Substances

  • Lactams
  • Oximes
  • Oleanolic Acid