Two studies on plant secondary metabolites are presented. First, alkaloids of Ungernia vvedenskyi (Chimkent oblast, previously unstudied) were investigated: Total alkaloid accumulation dynamics during vegetation (March 25–May 28, 1976) confirmed prior laws, with bulbs showing higher total alkaloids (up to 1.17%) and lycorine (up to 0.46%) than leaves; the species is a new lycorine source. Epigeal parts (May 25 collection) yielded lycorine, tazettine, ungminorine, ungminoridine, hippeastrine, galanthamine, narwedine, pancratine, hordenine, and base (I) (C₁₇H₁₉NO₅, mp 210–212°C, optically inactive), identified as racemic ungminorine via spectral characteristics (UV: λᴱᵗOHₘₐₓ 290 nm; IR: 3200–3400 cm⁻¹ (OH), 2840/1265 cm⁻¹ (OCH₃), 1610 cm⁻¹ (aromatic ring); NMR: aromatic protons at 6.82/6.83 ppm, methylenedioxy at 5.82 ppm, geminal hydroxy protons at 4.65 ppm) and melting point. Flowers contained 0.36% alkaloids, yielding lycorine, tazettine, and base (II) (C₁₉H₂₅NO₅, mp 148–150°C). Second, roots of Astragalus sieversianus (Chatkal range, Western Tien-Shan) were studied: Air-dry roots (5 kg) were methanol-extracted, concentrated to a syrup, partitioned with butanol, and precipitated with acetone. Part of the extract (10.0 g) was hydrolyzed (8% H₂SO₄ in methanol-water, 10 h), and sapogenins were purified via silica gel chromatography (chloroform-ethanol 50:1, then ethyl acetate) to yield 1.0 g of sieversigenin (C₃₀H₅₀O₅, mp 229–231°C, [α]ᴰ +67.1±2° (c 1.92, methanol)). IR showed OH (3450–3250 cm⁻¹) and double bond (3045/1640 cm⁻¹); MS revealed M⁺ 490 and fragments indicating a substituted tetrahydrofuran side chain. Oxidation with Jones reagent yielded a triketo derivative (C₃₀H₄₈O₅, mp 217–220°C, [α]ᴰ -58.4±2°), confirming three secondary/one tertiary hydroxy groups. Sieversigenin belongs to the tetracyclic terpenoid series and differs from reported triterpenoids.