A New Iridoid Alkaloid from the Flowers of Plumeria rubra L. cv. acutifolia

A new iridoid alkaloid containing a spirolactone unit, plumericidine ( 1 ), was isolated from the flowers of Plumeria rubra L. cv. Acutifolia. Its structure was elucidated by spectroscopic evidence and confirmed by X‐ray diffraction crystallography. Its anticancer and antiviral activities were evaluated, but found to be insignificant.     

Two New Iridoid Esters from the Root and Rhizome of Valeriana jatamansi Jones

Two new iridoid esters, named valerjatadoids A and B ( 1 and 2 , resp.), together with three known iridoid esters, jatamanin O ( 3 ), jatamanvaltrate P ( 4 ), and jatamanvaltrate Q ( 5 ), have been isolated from the root and rhizome of Valeriana jatamansi Jones . The structures of the two new compounds were elucidated by spectroscopic analyses, including 2D‐NMR techniques.     

Iridoid Glycosides and Phenolic Compounds from the Flowers of Vitex agnus‐castus

A new and rare type of iridoid glycoside, agnusoside ( 1 ), a new caffeoylquinic acid derivative, castusic acid ( 2 ), and a new sugar ester, 1,2‐di‐(4‐hydroxybenzoyl)‐β‐glucopyranose ( 3 ), along with ten known compounds belonging to iridoid glycosides (agnuside, trans‐eurostoside), caffeoylquinic acid derivatives (chlorogenic acid and isochlorogenic acid A), flavonoids (isoorientin, isovitexin, kaempferol 3‐O‐sophoroside, luteolin 6‐C‐(2′′‐O‐trans‐caffeoyl)glucopyranoside, and simple phenolic acids (4‐hydroxybenzoic acid, 3,4‐dihydroxybenzoic acid), chemical classes were isolated from the flowers of Vitex agnus‐castus. The structures of the isolates were established by extensive 1D‐ and 2D‐NMR spectroscopic analysis as well as HR‐ESI‐MS. Agnusoside ( 1 ) represents an unusual type of iridoid glycoside with its 6‐keto C(4) nonsubstituted aglycone.     

Iridoid glycosides-Kutkin,Picroside I,and Kutkoside from Picrorrhiza kurroa Benth inhibits the invasion and migration of MCF-7 breast cancer cells through the down regulation of matrix metalloproteinases: 1st Cancer Update

Ethnopharmacological relevanceIridoid glycosides have been associated with decreased risks of cancer, such as hepatocarcinoma. Although Picrorrhiza kurroa has shown activity against hepatocarcinogenesis, its mechanism of action is poorly understood, further the anticancer activity of iridoid glycosides present in this plant has not been tested so far.Aim of the studyHere, MCF-7 cell lines (Human breast cancer) were used to test whether P. kurroa extract (PE) and its isolated iridoid glycosides Picroside I (PS), Kutkoside (KS), and Kutkin (KT) exerts the anti-invasion activity via down-regulation of the expression of matrix metalloproteinases (MMPs). MMPs play an important role in solid tumor invasion and migration.Materials and methodsThe activity and expression of gelatinases (MMP-2 and MMP-9) and collagenases (MMP-1 and MMP-13), protein, and mRNA were detected by gelatin zymography, and RT-PCR. The migratory and invasive capacities of MCF-7 cell lines were measured by the wound scratch migration assay. The preliminary cytotoxicity testing was done by MTT assay and propidium iodide staining. Further the inhibition of inflammatory mediators was also done by quantification of nitrite inflammatory mediators.ResultsThe study showed that PE and its isolated iridoids glycosides PS, KS, and KT exhibited considerable cytotoxic potential in a dose-dependent manner. Further PE, PS, KS, and KT inhibited MCF-7 cell invasion and migration, and decreased MMP-2, 9 and MMP-1, 13 activities. Furthermore, PS, KS, and KT reduced MMPs expression at protein and mRNA levels, and suppression of the inflammatory mediators was also exhibited.ConclusionsOur results suggest that PS, KS, and KT may be the valuable anti-invasive drug candidates for cancer therapy by suppressing Collagenases and Gelatinases. PS, KS, and KT showed good results in comparison with PE. PS and KS exhibit almost comparable down regulation while KT exhibited maximum suppression of invasion, migration, and expression of MMPs.     

电喷雾离子源正离子模式下环烯醚萜苷的质谱裂解行为

利用高分辨率四极杆-飞行时间串联质谱(Q-TOF MS/MS)对环烯醚萜苷同系组分7,8-环戊烯型和环戊烷型环烯醚萜苷在电喷雾正离子(ESI⁺)模式下的质谱裂解行为进行了研究. 在ESI⁺模式下, 环烯醚萜苷主要的质谱裂解途径是脱去母环上的功能基团, 如丢失H₂O, CO₂, CH₃OH, CH₃COOH和糖单元部分等, 由于它们均为葡萄糖苷, 所以共有碎片离子[Glc+Na]⁺(m/z 185.0). 环烯醚萜苷母核环上半缩醛结构的异构化造成二氢吡喃环的断裂, 但未发现与苷元部分在负离子(ESI^-)模式下相同的其它断裂. 环烯醚萜苷在ESI⁺模式下的断裂途径特征性不如其在ESI^-模式下的明显, 且灵敏度比后者低.     

New humantenine-type indole alkaloids with iridoid unit from Gelsemium species

Two new oxindole alkaloids, rankiniridine (1) and humanteniridine (2), having a nitrogen-carbon linkage between a humantenine-type monoterpenoid indole alkaloid and a monoterpene unit with an iridoid skeleton, were isolated from Gelsemium rankinii and Gelsemium elegans, respectively.     

Biridoside,A New Iridoid from Buddleja davidii

The methanolic extract of fresh and dried leaves of Buddleja davidii furnished a new iridoid glycoside, along with other known compounds. Spectroscopic techniques were utilized for the characterization of biridoside.     

Total Synthesis of (±)-Iridolactone

A total synthesis of (±)-iridolactone ( 1 ) from bicyclo[2.2.1]ketone 6 is described. Trisubstituted cyclopentenoid aldehyde 7 is a key intermediate.     

Two New Iridoid Alkaloids,Daphmacropodosidines A and B,from Daphniphyllum macropodum

Two new iridoid alkaloids, daphmacropodosidines A ( 1 ) and B ( 2 ), together with two known ones, daphcalycinosidine B and caldaphnidine F, were isolated from the fruits of Daphniphyllum maropodum. Their structures were established by spectral methods, especially 2D NMR spectra (¹H,¹H‐COSY, HMQC, HMBC, and NOESY), as well as chemical means.