Ten New Labdane-Type Diterpenes from the Fruit of Vitex rotundifolia.

Abstract

Ten new labdane-type diterpenes were isolated from the fruit of Vitex rotundifolia L. (Verbenaceae), along with a known diterpene, vitexilactone. Their chemical structures were determined on the bases of spectroscopic data.

Two New Steroid Glycosides and a New Sesquiterpenoid Glycoside from the Underground Parts of Trillium kamtschaticum

“…All instruments and materials used were the same as those cited in a previous report 18) unless otherwise specified. Plant Material The underground parts of T. kamtschaticum were collected in Hokkaido prefecture, Japan, in May 2003 and identified by Professor Toshihiro Nohara, Faculty of Pharmaceutical Sciences, Kumamoto University.…”

A new labdane diterpene fromVitex negundo

“…These data suggested that 1a was a labdane-type diterpene having one each of a spiro-tetrahydrofuran ring, γ-spiro-lactone ring, hydroxyl group and acetoxy group. Further comparison of the 1 H and 13 C NMR data of 1a with those of (rel 5S, 6R, 8R, 9R, 10S, 13S, 16S)-6-acetoxy-9, 13-epoxy-16-methoxy-labdan-15, 16-olide (2), which was previously isolated from the fruits of Vitex rotundifolia (Ono et al, 2001), led to the assumption that 1a is a 16-O-demethyl regioisomer of 2 with an acetoxyl group at C-3 instead of C-6, which was confirmed by detailed HMBC and 1 H-1 H COSY spectroscopic analysis (Figure 3). In the NOESY spectra of 1a, correlations were observed between H-8/H-20, H-19/H-20, H-3/H-18, H-5/H-3, H-14/H-17 and H-1/H-16, indicating a β-orientation for H-8, H-19, and H-20 and an α-orientation for H-3, H-5, H-17, and H-18.…”

New Iridoid Glucosides from the Aerial Parts of Verbena brasiliensis

“…All the instruments and the materials used were the same as cited in the previous report 16) unless otherwise specified. Plant Material The aerial parts of V. brasiliensis were collected in Kumamoto prefecture, Japan, in August 2001, and identified by Professor Toshihiro Nohara, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University.…”

“…1,2) In the course of our studies on Verbenaceae plants and natural antioxidants, we examined the constituents of the MeOH extract of the aerial parts of V. brasiliensis. The present paper describes the isolation and structural elucidation of two new iridoid glucosides (1, 2), along with six known iridoid glucosides (3)(4)(5)(6)(7)(8), three known phenylethanoid glycosides (9-11), two known lignan glucosides (12, 13), a known methyl salicylate glucoside (14), and two known sterols (15,16), as well as the radical-scavenging effects of 1 and 2.…”