In the flora of Turkey, genus Veronica L. (Scrophulariaceae) is represented by 79 species, 26 of which are endemic.1) Some of the Veronica species are used as diuretics and for wound healing in traditional Turkish medicine.2) Several Veronica species are used for the treatment of cancer, influenza, hemoptysis, laryngopharyngitis, hernia, and against cough, and respiratory diseases plus as an expectorant and antiscorbutic in different countries.3-5) Veronica species contain mainly iridoid glucosides, especially benzoic and cinnamic acid esters of catalpol, some phenylethanoid and flavonoid glycosides.6-11) Previously, we noted that the water soluble portion of the MeOH extract of Veronica pectinata L. var. glandulosa RIEK ex M.A. Fisher showed a suppressive effect on nitric oxide production in lipopolysaccharide-stimulated mouse peritoneal macrophages.12) As part of the continuation of this work, we report here the isolation and structural elucidation of phenylethanoid glycosides, as well as their free radical scavenging activities, from the active fraction of Veronica pectinata var. glandulosa.
Results and DiscussionCompound 1 was obtained as an amorphous powder with negative optical rotation ([a] D 23 Ϫ58°, MeOH). Its structure was identified as ehrenoside by comparison of its spectral data with those reported in literature. Tables 1, 2) of 2 and 1, and by nuclear Overhauser effect spectroscopy (NOESY) correlation between d 3.88 and the H-2ЉЉ signal [d 7.20, (1H d, Jϭ2.1 Hz)]. These indicated that compound 2 contained (E)-feruloyl instead of (E)-caffeoyl as an acyl ester moiety. Furthermore, the above deduction was supported by a heteronuclear multiple bond correlation (HMBC) experiment (Fig. 2). From the above results, compound 2 was determined to be 2- Sciences, Nagoya City University; 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan. Received November 26, 2001; accepted January 29, 2002 A known phenylethanoid glycoside, ehrenoside (