We have investigated the alkloidal constituents of Aconitum barbatum, A. kusnezoffii, A. volubile, and Delphinium cheilanthum collected in Mongolia. Seven norditerpenoid and seven diterpenoid alkaloids were isolated and identified from these plants. 1H Decoupled 13C, 2D 1H phase sensitive COSY, ROESY, TOCSY, HMQC-TOCSY and HMBC NMR spectral studies were carried out on denudatine and lepenine to make definitive assignments for the carbon atoms of these alkaloids.