We have investigated the leaves of H. latifolium collected in the period of vigorous flowering and the beginning of fruit bearing of the plant (May 13, 1974) in the Chimkent oblast, Ostantsovye mountains, Alimtau, "Syrdar'ya" sovkhoz [state farm]. The comminuted plant was extracted with methanol. The methanol was evaporated off and the residue was treated with 10% sulfuric acid from which, after the addition of an excess of ammonia, the alkaloids were extracted with ether. When the ethereal solution was concentrated, crystals of skimmianine (I) deposited in an amount of 0.27% of the weight of the dry plant. The mother solution after the isolation of (I) was chromatographed on alumina, yielding another 0.03% of (I) and a new base (II) with the composition C₁₉H₁₉O₅N, mp 139-140°C (benzene), M⁺ 329, which we have called haplatine. Haplatine is readily soluble in organic solvents and dilute acids and insoluble in water and aqueous alkali. IR, UV, NMR, and mass spectra showed properties similar to those for 7-isopentenyloxy-γ-fagarine, from which (II) differs by a hydroxymethyl group in place of a methyl group. Acetylation of (II) with acetic anhydride in pyridine gave a monoacetyl derivative (III) with mp 87-88°C (acetone-ether), composition C₂₀H₂₁O₆N. Hydrolysis of (III) with concentrated hydrochloric acid yielded haplopine (IV), confirming the structure of haplatine. Haplatine has not been found previously in the plant H. latifolium collected in the Tashkent oblast.