547.94:547.834.2 N. Z. Baibulatova, L. V. Spirikhin, M. S. Yunusov, N. S. Makara, N. Zh. Baschenko, and V. A. Dokichev Derivatives of N-(2-hydroxyethyl)cytisine, N-(2-hydroxypropyl)-, N-(2-hydroxy-2-(1-adamantyl)ethyl)-, and N-(2-hydroxy-2-phenylethyl)cytisine, were synthesized by reduction of N-(2-oxopropyl)-, N-(2-oxo-2-(1-adamantyl)ethyl)-and N-(2-oxo-2-phenylethyl)cytisine with metal hydrides. The antiarrhythmic and analgesic activities of the prepared compounds were investigated.Cytisine (1) and its derivatives are attractive to researchers owing to their broad spectrum of physiological activity (spasmolytic [1], insecticidal [2], cholinergic [3], analgesic [4]) and the ability to use them in catalytic reactions as optically active ligands [5]. We recently showed that N-(2-hydroxyethyl)cytisine has low toxicity and exhibits high antiarrhythmic activity compared with known antiarrhythmics [6,7].The goal of the present work was to synthesize new cytisine derivatives [8][9][10][11] and to study the structure-activity (antiarrhythmic) relationship for N-(2-hydroxyethyl)cytisine derivatives. Thus, we synthesized N-(2-hydroxypropyl)-(4a), N-(2-hydroxy-2-(1-adamantyl)ethyl)-(4b), and N-(2-hydroxy-2-phenylethyl)cytisine (4c) via reduction of the corresponding 2-alkyl-or 2-phenyl substituted N-(2-oxoethyl)cytisines 3a-c, which were prepared by reacting 1 and bromoketones 2a-c. R = Me (a), Ad (b), Ph (c)Ketones 3a-c were prepared by reacting 1 with bromoketones [bromoacetone (2a), 1-adamantyl-2-bromomethylketone (2b), bromoacetophenone (2c)] in anhydrous acetone in the presence of K 2 CO 3 for 1 h in 95-99% yields.The reduction of these ketones with NaBH 4 , LiAlH 4 , (i-Bu) 2 AlH, and AlH 3 ·N(Me) 3 was studied in order to investigate the effect of the optically active center of cytisine and the nature of the metal hydride on the new asymmetric center formed by conversion of the carbonyl in 3a-c into a secondary alcohol.