Crystal structure of sepaconitine, a C ₁₉-diterpenoid alkaloid from the roots of Aconitum sinomontanum Nakai

Abstract

The title compound [systematic name: [(1α,14α,16β)-20-ethyl-8,9,10-trihy­droxy-1,14,16-tri­meth­oxy­aconitan-4-yl 2-amino­benzoate], C ₃₀H ₄₂N ₂O ₈, a natural C ₁₉-diterpenoid alkaloid, possesses an aconitane carbon skeleton with four six-membered rings and two five-membered rings. The fused ring system contains two chair, one boat, one twist-boat and two envelope conformations. Intra­molecular N—H⋯O hydrogen bonds are observed between the amino and carbonyl groups. The mol­ecules are linked together via O—H⋯O hydrogen bonds, forming a three-dimensional framework.