Two New Iridoid Glucosides from Clerodendrum serratum

Two new iridoid glucosides, named 7 beta -coumaroyloxyugandoside (1) and 7 beta - cinnamoyloxyugandoside (2) were isolated from the leaves of Clerodendrum serratum, and their structures were elucidated by spectral means.

A New Iridoid Glucoside from Lagotis yunnanensis

Phytochemical investigation of Lagotis yunnanensis led to the isolation and identification of a new iridoid glucoside 1, named as 10-O-(3,4-dimethoxy-(E)-cinnamoyl)aucubin. Its structure was elucidated by spectroscopie methods.

Isolation and Purification of Unstable Iridoid Glucosides from Traditional Chinese Medicine by Preparative High Performance Liquid Chromatography Coupled with Solid-phase Extraction

An efficient preparative method was successfully developed for isolation and purification of unstable components from medicinal plant extracts, using a combined method of preparative high performance liquid chro-matography(HPLC) and solid-phase extraction(SPE). The aim of this study was to obtain an effective method with high preparative efficiency and importantly to avoid the transformation of unstable compounds. The preparative HPLC system was based on an LC/MS controlled four-channel autopurification system. The SPE method was performed with a C18 packing material to trap the target compounds and to remove the acidic additive derived from the mobile phase. Using this method, the unstable iridoid glucosides(IGs) as model compounds were successfully isolated and purified from the extract of Hedyotis diffusa Willd. Six IGs(including one new minor IG) and one nucleotide compound were simultaneously obtained, each with a purity of 91% as determined by HPLC. The structures of the isolated compounds were identified by UPLC/Q-TOF MS, UV, 1D and/or 2D NMR. It was demonstrated that the combination of preparative HPLC with SPE is a versatile tool for preparative purification of unstable compounds from complex natural products.

Two New Iridoid Glucosides from Lagotis yunnanensis

Two new iridoid glucosides 1 and 2, 10-O-(3, 4-dimethoxy-(E)-cinnamoyl)catalpol and 10-O-(3, 4-dimethoxy-(Z)-cinnamoyl)catalpol, were isolated from Lagotis yunnanensis. Their structures were elucidated by spectroscopic methods.

Iridoid glucosides from Allamanda neriifolia

A new iridoid glucoside,allamanoid(1),was isolated from the aerial parts of Allamanda neriifolia,together with three known glucosides,plumieride,protoplumericin,and nicotiflorin.Their structures were elucidated by 1D and 2D spectroscopic analyses, hydrolysis,and comparison with literature data.

New iridoid glucoside from Wendlandia tinctoria roots

A new iridoid glucoside,10-O-veratroyleranthemoside（1） was isolated from the roots of Wendlandia tinctoria.The structure was established by spectroscopic（including 2D NMR） and chemical methods.

Genipin and geniposide from Gardenia jasminoides:An overview of their anti-cancer and other pharmacological properties

Genipin and geniposide are iridoids from the fruits of Gardenia jasminoides.Both compounds have a methyl acetate(-COOCH_(3))group at C4 and a hydroxyl(-OH)group at C10.As an iridoid glucoside with a glucose moiety at C1,geniposide is also known as genipin-1-O-β-D-glucoside.Without the glucose moiety,genipin is an iridoid and the aglycone of geniposide.The-OH group at C1 of genipin is responsible for its cytotoxic effects.Geniposide without the-OH group at C1 lacks the cytotoxic effects.There are more publications on the anti-cancer properties of genipin than geniposide.Studies have reported the potentiation of genipin when used in combination with anti-cancer drugs.The anti-cancer properties of geniposide have been investigated using human intestinal microflora that hydrolyzes geniposide to genipin.Both genipin and geniposide exert antiproliferative and apoptotic activities via different molecular targets and pathways.Other pharmacological properties of genipin and geniposide include antidepressant,antidiabetic,anti-inflammatory,anti-obesity,anti-thrombotic,hepatoprotective,and neuroprotective activities.Future research on genipin and geniposide is suggested.

Protein Tyrosine Phosphatase 1B Inhibitors from Plantago asiatica

Objective To identify the active compounds for protein tyrosine phosphatase 1B(PTP1B) from the seeds of Plantago asiatica.Methods Bioassay-guided fractionation resulted in the isolation of iridoid glucosides(1-5) with PTP1B inhibitory activity.Results Five compounds were identified as desacetylhookerioside(1),melittoside(2),geniposidic acid(3),10-O-acetyl-geniposidic acid(4),and alpinoside(5).Conclusion Isolated compounds 35 inhibit PTP1B with IC50 values ranged from(16.3 ± 1.1) to(19.8 ± 1.2) μmol/L.