Synthesis of 1,10-seco-triterpenoids by the Beckmann fragmentation from allobetulin

• DOI: 10.1016/j.tet.2017.09.044
• Publication Date: 2017-09-28T07:03:26Z
• Authors: Irina A. Tolmacheva; Alexey V. Nazarov; Maxim V. Dmitriev; Eugene I. Boreko; Victoria V. Grishko
• Keywords: Beckmann rearrangement; Stereocenter; Oleanane; Terpene; Absolute Configuration; Fragmentation

Abstract A new convenient route to synthesize 1,10-seco-triterpenoids from allobetulin was demonstrated. Stereoisomerism of starting oleanane 1-oximes was determined by X-ray crystallography and additionally confirmed by the structure of the obtained Beckmann rearrangement products. Absolute configuration of chiral centers of 1,10-secotriterpenoids was found to be identical to that of stereocenters in respective precursors. Antiviral activity of 1,10-seco-derivatives was studied against herpes simplex virus type I.