The alkaloids of Buxus sempervirens L. (common box) cultivated in the environs of Kislovodsk, which had not been studied before, were investigated using samples collected on May 21, 1978. The alkaloid contents in different parts were determined: 2.39% in first-year shoots, 2.11% in young roots, 1.64% in leaves and small branches, 1.94% in flowers, and 1% in old branches. Through chloroform extraction, separation by McIlvaine's solutions according to basicity (pH 8.0-2.2), and column chromatography on alumina, three alkaloids were isolated and identified as cyclobuxine D (I, C25H42N2O, mp 241-243°C), cyclovirobuxine D (II, C26H46N2O, mp 228-230°C), and cycloprotobuxine A (III, C28H50N2, mp 200-202°C), along with a new base (IV, mp 127-129°C) belonging to the 9β,19-cyclo-5α-pregnane type. Continuing the separation of combined alkaloids from the epigeal part of Nitraria sibirica Pall. collected near Rybach'e, Kirghiz SSR, three more bases were isolated in addition to previous ones: base (I) C15H24N2O (mp 82-84°C, [α]D ±0°) identified as nitraramine; base (II) C11H10N2O2 (mp 204-205°C, [α]D -91°) identified as L-vasicinone (first isolated from this genus); and base (III) C10H19NO (mp 75-76°C, [α]D ±0°) identified as the previously undescribed racemic form of nitramine.