RESUMO
<p><b>AIM</b>To study the chemical constituents of Pseudotsuga sinensis Dode (Pinaceae).</p><p><b>METHODS</b>To separate the constituents of P. sinensis by using various kinds of chromatography and identify their structures on the basis of spectral analysis.</p><p><b>RESULTS</b>Six compounds were isolated from P. sinensis. Their structures were established as 5,7,4'-trihydroxy-6-methylflavanone (poriol, I), 3,5,7,3',4'- pentahydroxyflavonone (quercetin, II), 5,7,3',5'-tetrahydroxy-6- methylflavanone (III), 5,7,3',5'-tetrahydroxyflavanone (IV), 3,5,7,3',5'-pentahydroxyflavanone (V) and 5-hydroxy-6-methylchromone-7-O-beta-D-glucopyranoside (VI) based on the analysis of spectral data of IR, UV, MS, 1D and 2D-NMR.</p><p><b>CONCLUSION</b>Compounds III and VI are new compounds. All of six compounds were isolated from this plant for the first time.</p>