Alstolarines A and B, two unusual monoterpenoid indole alkaloids with an acetal moiety from <i>Alstonia scholaris</i>

Abstract

Two novel monoterpenoid indole alkaloids, alstolarines A and B (<bold>1</bold> and <bold>2</bold>), were isolated from <italic>Alstonia scholaris</italic>, and exhibited promising vasorelaxant activities.