Four new phenylpropanoid derivatives, barbatosides A-D, and a new catechin, barbatoflavan, were isolated from the whole plant of Campanula barbata L. (Campanulaceae) and identified as wahlenbergioside-3'-O-glucoside, wahlenbergioside-3'-O-(2"'-(p-methoxycinnamoyl))-glucoside, wahlenbergioside-3'-O-(4"'-(trans-p-coumaroyl))-glucoside, wahlenbergioside-3'-O-(4"'-(cis-p-coumaroyl))-glucoside and 3-acetyl-5-methoxy-7,3',4'-trihydroxy-8-O-glucoside-flavan-3-ol, respectively, by spectroscopic methods. In addition, four flavonols were isolated and identified as kaempferol-3-O-glucoside, kaempferol-3-O-rutinoside, quercetin-3-O-glucoside and quercetin-3-O-rutinoside. Barbatoflavan demonstrated scavenging properties towards the DPPH radical. (C) 2001 Elsevier Science Ltd. All rights reserved.