We investigated the epigeal part of Aconitum karakolicum collected in the upper reaches of the R. Tyup (KirgSSR) in the budding period. The amount of combined alkaloids was 0.56% of the weight of the dry plant. The quantitative ratio and qualitative composition of the alkaloids of the epigeal part differed substantially from those for the tubers (main component aconitine). We isolated songorine, napelline and a base with mp 205-206°C (composition C24H35NO4, 1), which was readily soluble in chloroform and ethanol and less readily in acetone and ether. NMR spectrum showed it contained a N-ethyl group (1.01 ppm, 3H, triplet), a tertiary C-methyl group (0.70 ppm, 3H, singlet), an acetoxy group (1.91 ppm, 3H, singlet), and a terminal methylene group. Acetylation with acetic anhydride in pyridine formed a diacetyl derivative (II, mp 224-226°C, acetone) with three acetoxy groups in NMR. Mass spectrum of 1 had the molecular ion peak and peaks of ions M - 17, M - 43, and M - 59. Alkaline hydrolysis gave an amino alcohol identified as napelline, so the base was napelline monoacetate. Oxidation with silver oxide gave an anhydrohydroxy derivative (III, C24H33NO4) with M - 56 peak (showing C-1 hydroxy not esterified). Mass spectra analysis of 1 and II (comparing M - CH3CO and M - CH3COO peaks) located the acetoxy group at C-11, suggesting structure 1 as the most probable for the alkaloid.