Cyclic Peptides, Acyclic Diterpene Glycosides and Other Compounds from Lycium chinense MILL.

Abstract

The chemical structures of four cyclic peptides, lyciumins A-D (1-4), three acyclic diterpene glycosides, lyciumosides I-III (5-7) and other three compounds, a tryptophan derivative glycoside (8), a monoterpene glycoside (9) and a steroidal glycoside (10) isolated from Lycium chinense, have been elucidated by a combination of chemical, 1H- and 13C-NMR, and mass spectrometric studies. Lyciumins are interesting because of their monocyclic octapeptides containing a novel C-N linkage between tryprophan N1 and glycine C alpha.

Geranyllinalool Synthases in Solanaceae and Other Angiosperms Constitute an Ancient Branch of Diterpene Synthases Involved in the Synthesis of Defensive Compounds

“…(Van Poecke et al, 2001;Ament et al, 2004;Williams et al, 2005;Hopke et al, 1994;Leitner et al, 2010;Webster et al, 2010). In addition, various hydroxygeranyllinalool glycosides have been isolated from many Solanaceous species such as Capsicum annuum, Lycium chinense, and at least 26 Nicotiana species (Yahara et al, 1993;Iorizzi et al, 2001;Snook et al, 1997).…”

Phytochemical and Biological Studies of Lycium Medicinal Plants

“…Lyciumoside I purified from leaves, stems, and root barks of L. chinense showed significant antimicrobial activity against Helicobacter pylori [29] [37] [124].…”

A New Acyclic Diterpene from Trigonotis peduncularis

“…The configuration of the D-glucopyranose was determined as β from the coupling constant (J = 8.0 Hz) of the anomeric proton signal at δ H 4.33 in the 1 H-NMR spectrum of compound 3. 7 We concluded from all the above evidence that compound 3 is an acyclic diterpene glucopyranoside with three hydroxyl groups, three double bonds including an exomethylene, and a β-D-glucopyranoside. Determination of the final structure of compound 3, including the location of the functional group, was accomplished by 2D NMR experiments such as gradient correlated spectroscopy (gCOSY), gradient heteronuclear single quantum correlation (gHSQC), and gradient heteronuclear multiple bonding connectivity (gHMBC).…”

“…The two known compounds 1 and 2 were identified as phytol (yield: 1.7 × 10 −3 %, 1) and lyciumoside III (yield: 5.1 × 10 −4 %, 2), respectively, through the comparison of several spectroscopic data with those of the literature. 7 Compound 2, lyciumoside III, was previously isolated from Lycium chinensis Mill along with lyciumoside I-IX. 7,8 However, this is the first report of isolation of these acyclic diterpenoids (1 and 2) from T. peduncularis.…”

“…7 Compound 2, lyciumoside III, was previously isolated from Lycium chinensis Mill along with lyciumoside I-IX. 7,8 However, this is the first report of isolation of these acyclic diterpenoids (1 and 2) from T. peduncularis.…”