UDC 547.972Sorbus tianschanica Rupr. (Tien-Shan mountain ash) is a diminutive tree or bush of the family Rosaceae that is distributed in mountainous regions of Central Asia and eastern China. It is used in Xinjiang Autonomous Region of the P. R. China as an anti-inflammatory agent and to treat tuberculosis, asthma, and gastritis [1]. We investigated the chemical composition of leaves and flowers of S. tianschanica.Air-dried leaves (2.5 kg) were extracted (3u) at room temperature by ethanol (60%). The extracts were combined and evaporated to dryness in vacuo. The resulting powder (430 g) was diluted with water and treated successively with petroleum ether, EtOAc, and n-BuOH. Solvents were evaporated to produce PE (18.0 g), EtOAc (15.0 g), and n-BuOH (20.0 g) extracts.The EtOAc extract (15.0 g) was chromatographed over a column of silica gel with elution by a gradient of CHCl 3 :MeOH (95:5o65:35) to isolate 1-6.Palmitic acid (1), CH 3 (CH 2 ) 14 COOH, mp 60-61°C. EI-MS (m/z, %): 256 (36) [M] + , 129 (50), 115 (15), 98 (10), 85 (15), 73 (40), 60 (28). PMR spectrum (600 MHz, CDCl 3 , G, ppm, J/Hz): 2.37 (2H, t, J = 7.2), 1.62 (2H, m, J = 7.2), 1.24-1.31 (24H, m, J = 7.2), 0.88 (3H, m). 13 C NMR spectrum (150 MHz, CDCl 3 , G, ppm): 179.91 (C-1), 34.02 (C-2), 24.78 (C-3), 27.96 (C-4), 29.23 (C-5),