From the phenolic fraction of the combined alkaloids of the epigeal part of Corydalis ledebouriana K. et K. collected in the Fergana range in the basin of the R. Kugart in the flowering period, a new base named corledine (I) was isolated, with mp 210-212°C (methanol), [α]D--100°(c 0.2; methanol), sparingly soluble in acetone, benzene, ether, and chloroform, and readily soluble in alkaloids. Its UV spectrum (λmax^ethanol 221, 290, 326 nm, log ε 4.35, 3.44, 3.51), IR spectrum (absorption bands at 920, 1040 (methylenedioxy group), 1610 (aromatic ring), 1750 (carbonyl group), 3350 (hydroxy group) cm⁻¹), and mass spectrum (maximum ion m/e 192, along with ions m/e 177, 149, 135) enabled assignment to the phthalide-isoquinoline alkaloids. The PMR spectrum of (I) (CDCl₃, δ -- HMDS) showed signals: singlets at 2.60 (3H, N-CH₃), 3.74 (3H, OCH₃), 5.98 (2H, -OCH₂O-), 6.35 and 6.63 (1H each, p-aromatic protons); doublets at 4.02 (1H, J=3.8 Hz, C₁-H), 5.61 (1H, J=3.8 Hz, C₉-H), 6.80 and 7.14 (1H each, J=8.0 Hz, o-aromatic protons); a multiplet at 2.22-3.04 ppm (protons of the methylenedioxy groups); and a strongly broadened signal at 4.90 ppm (hydroxy group). Acetylation of the base with acetic anhydride in pyridine gave an O-acetyl derivative with mp 162-164°C. Methylation of compound (I) with diazomethane yielded O-methylcorledine (II) with mp 179-180°C, which was identical to l-adlumine in terms of UV, IR, PMR, and mass spectra, as well as mixed melting point. To establish the mutual positions of the methoxy and hydroxy groups, intramolecular nuclear Overhauser effect (NOE) measurements were used. When the protons of the methoxy group were irradiated with a strong radiofrequency field, the intensity of the signal of one of the p-aromatic protons (singlet at 6.63 ppm) increased by 26%. Furthermore, irradiation of the C₁-H proton increased the intensity of the same signal by 27%, leading to the unambiguous assignment of the singlet at 6.63 ppm to the C₈-H proton and the methoxy and hydroxy groups at C₇ and C₆ respectively. Based on these facts, the structure of corledine was established.