From 10 g of the feebly basic fraction of the combined alkaloids of Vinca erecta collected in the Tashkent oblast we have isolated by chromatography on a column of alumina an amorphous base with the composition C22H24N2O3 (I). Its UV spectrum [λmax 223, 280 (log ε 4.07, 3.66)] is characteristic for the indolenine alkaloids. IR spectrum of (I) (KBr), cm⁻¹: 860, 825, 780 (1,2,4-trisubstituted benzene ring), 1745 (OCOCH3). In the mass spectrum of (I) the peaks of ions with the following m/e numbers were found: 364 (M⁺; 100%), 321 (63%), 305 (42%), 212 (10%), 199 (21%), and 198 (38%). In the NMR spectrum of the base (δ scale, CDCl3) there were the signals of the protons of the following groups: >C=CH-CH3 (1.60 ppm, doublet; 5.25 ppm, quartet, J=6 Hz), >CH-OCOCH3 (2.10 ppm, singlet; 5.00 ppm, singlet), Ar-OCH3 (3.75 ppm, singlet), and three aromatic protons C9H at 6.97, C11H at 6.86, and C12H at 7.45 ppm (J H9H11=2 Hz; J H11H12=7 Hz). Consequently, the base is a substituted indolenine derivative. The difference of 30 mass units in the positions of all the peaks of the ions in the mass spectrum from those for vinorine and the presence in the NMR spectrum of the base of the signal of the protons of a methoxy group permitted the conclusion that it was a methoxy derivative of vinorine. According to the IR spectra, the methoxy group could be at C10 or C11. The reduction of (I) with lithium tetrahydroaluminate gave a product (II) with mp 198-200°C. The IR spectrum of (II) showed a broad absorption band at 3200 cm⁻¹ (NH, OH). Its mass spectrum had the peaks of ions with m/e 324 (100%), 309 (10%), 307 (11%), 294 (11%), 293 (41%), 279 (10%), 199 (54%), and 198 (53%), similar to those for lochnerine. By comparing the Rf values, coloration with cerium sulfate reagent, the mass spectra, and the melting point, (II) was identified as lochnerine, which has a methoxy group at C10. Thus, the base (I) has the structure of 10-methoxyvinorine.