Crystal structure of N-de­acetyl­lappa­coni­tine

The title compound, C30H42N2O7 [systematic name: (1S,4S,5S,7S,8S,9S,10S,11S,13R,14S,16S,17R)-20-ethyl-4,8,9-trihy-droxy-1,14,16-tri-meth-oxy-aconitan-4-yl 2-amino-benzoate], isolated from roots of Aconitum sinomontanum Nakai, is a typical aconitane-type C19-diterpenoid alkaloid, which crystallizes with two independent mol-ecules in the asymmetric unit. The conformations of the two independent mol-ecules are closely similar. Each mol-ecule comprises four six-membered rings (A, B, D and E) including one six-membered N-containing heterocyclic ring (E), and two five-membered rings (C and F). Rings A, B and E adopt chair conformations, while ring D displays a boat conformation. Five-membered rings C and F exhibit envelope conformations. IntramolecularN-H⋯O hydrogen bonds between the amino group and carbonyl O atom help to stabilize molecular structure. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into zigzag chains propagating in [010].