A new iridoid diglucoside from Harpagophytum procumbens

A new iridoid diglucoside has been isolated from an aqueous extract of Harpagophytum procumbens secondary roots, together with six known compounds. Its structure has been assigned as 6′-O-glucopyranosyl-8-O-trans-coumaroylharpagide by spectroscopic means.     

Secondary metabolites from Scrophularia canina L.

A re-examination of Scrophularia canina L. confirmed the presence of iridoid glucosides considered as chemotaxonomic markers for the Scrophulariaceae family, like aucubin, harpagide and 8-O-acetylharpagide, besides the further presence of 8-epiloganic acid, which is, indeed, considered the biogenetic precursor of iridoids normally found in Scrophulariaceae, and was recognised here for the first time in the studied species. Also verbascoside and (E)-phytol were evidenced for the first time in S. canina. The former compound is an almost ubiquitous glycosidic phenyl-ethanoid, which attains systematic importance when in co-occurrence with iridoids, and its taxonomical implications were discussed. The latter compound, even though it is omnipresent, is interestingly endowed with several biological activities, which may give an additional reason for the traditional uses of this plant.     

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.     

藏药蓝翠雀花中的新二萜生物碱

蓝翠雀花(Delphinium caeruleum Jacq.ex Camb.)~[1]在甘肃西南部、西藏、青海等地分布较广,藏民常用其治疗牙痛、跌打损伤.其化学成分迄今未见报道.我们将其全草用乙醇浸泡,石油醚脱脂,乙醚除去色素,酸碱常法处理,氯仿萃取得总生物碱.用氧化铝、硅胶进行多次柱层析及硅胶薄层制备层析,分得碱(1)～(4).     

Determination of five major iridoid glucosides in Flos Lonicerae by high-performance liquid chromatography coupled with evaporative light scattering detection

This study presents a new HPLC method using evaporative light scattering detection for the simultaneous determination of live major iridoid glucosides, namely 7-epi-loganin, sweroside, loganin, 7-epi-vogeloside, and secoxyloganin in Flos Lonicerae, an important traditional Chinese medicinal herb. The optimal conditions of separation and detection were achieved on a C18 analytical column with an isocratic mobile phase consisting of methanol-water (30:70, v/v) containing 0.5% acetic acid at the flow-rate of 1.0 ml/min, temperature for the detector drift tube set at 90 degrees C and the nitrogen flow-rate of 2.6 l/min. The limit of detection (S/N = 3) is less than 35.1 microg/ml and the limit of quantification (S/N = 10) is less than 140.1 microg/ml. All calibration curves show good linear regression (r2>0.996) within test ranges. This method provides good reproducibility for the quantification of the major iridoid glucosides in four Lonicera species with overall intra- and inter-day variation of less than 5% and 9%, respectively. The assay was successfully applied to quantify the main iridoid glucosides in the herb and to identify the botanical origin of Flos Lonicerae.     

Iridoid Glucosides from Eremostachys moluccelloides Bunge

From the aerial parts of Eremostachys moluccelloides Bunge , a new iridoid glucoside, lamalbidic acid ( 7 ), was isolated as its choline salt 7a together with six known iridoid glucosides, 5‐deoxysesamoside ( 1 ), 6β‐hydroxy‐7‐epiloganin ( 2 ), lamalbide ( 3 ), shanzhiside methyl ester ( 4 ), sesamoside ( 5 ), and 5‐deoxypulchelloside I ( 6 ). The structures of 7a and 7 (obtained from 7a ) were elucidated by spectroscopic (UV, IR, 1D‐ and 2D‐NMR, and ESI‐MS) methods.     

Robustolides A-C, three new briarane-type diterpenoids from the female gorgonian coral Ellisella robusta (Ellisellidae)

Three new briarane-type diterpenoids, designated as robustolides A-C (1-3), were obtained from the female gorgonian coral Ellisella robusta. The structures of briaranes 1-3 were elucidated by the interpretation of spectral data analysis and the structure of 1 was further confirmed by a single-crystal X-ray diffraction analysis. Briaranes 1 and 2 were found to show weak activity against the bacteria Pseudomonas aeruginosa and Staphylococcus aureus.