8-Epiloganin

Synthesis of deuterium-labelled substrates for the study of oleuropein biosynthesis in Olea europaea callus cultures.[Pubmed:26407195]

Nat Prod Res. 2016;30(8):926-34.

We propose the cell culture approach to investigate oleuropein (1) biogenesis in Olea europaea L. We suggest employing olive callus cultures to identify the iridoidic precursor of oleuropein. In fact, we confirmed that callus cells from olive shoot explants are able to produce key secoiridoid as 1. To enable this approach, we synthesised and characterised deuterium-labelled iridoidic precursors belonging both to the loganin and the 8-Epiloganin series. These iridoids are [7,8-(2)H2]-7-deoxy-8-epi-loganin (2(D)), [8,10-(2)H2]-8-epi-loganin (4(D)) and [7,8-(2)H2]-7-deoxy-loganin (3(D)).

Secondary metabolites isolated from Castilleja rubra exert anti-inflammatory effects through NF-kappaB inactivation on lipopolysaccharide-induced RAW264.7 macrophages.[Pubmed:24062082]

Arch Pharm Res. 2014 Jul;37(7):947-54.

8-Epiloganin (1), mussaenoside (2), and 5-O-caffeoylshikimic acid (3) have been isolated from Castilleja rubra, and the anti-inflammatory properties of these metabolites in a cell culture system were investigated. Compounds 1-3 suppressed not only the production of nitric oxide (NO) and prostaglandin E2, but also the expression of inducible NO synthase and cyclooxygenase-2 induced by lipopolysaccharide (LPS) in the RAW264.7 murine macrophage cell line. Compounds 1-3 also inhibited the release of pro-inflammatory cytokines induced by LPS, namely, tumor necrosis factor-alpha and interleukin-1beta. The underlying mechanism of the anti-inflammatory action of compounds 1-3 was associated with downregulation of nuclear factor-kappaB.

Iridoids from Bellardia trixago (L.) All.[Pubmed:23298403]

Nat Prod Res. 2013 Aug;27(15):1413-6.

The phytochemical study of the polar fraction of Bellardia trixago (L.) All. led to the isolation of eight iridoid glucosides. Five of these glucosides (aucubin (1), bartsioside (2), melampyroside (3), mussaenoside (4) and gardoside methyl ester (5)) were confirmed as they were previously isolated from this plant, and the remaining three known compounds (mussaenosidic acid (6), geniposidic acid (7) and 8-Epiloganin (8)) were isolated here for the first time. Of particular interest were the presence of 7 and 8 due to two reasons: the first one because it is not accompanied with geniposide, the corresponding methyl ester, as in the case of 4 and 6, and the second one because it is the parent compound of iridoids characteristic of Orobanchaceae family. Also an alditol, D-mannitol (9), was recognised for the first time from this species.

Iridoid and lignan glycosides from Citharexylum spinosum L.[Pubmed:16439350]

Nat Prod Res. 2006 Feb;20(2):201-5.

From the aerial parts of Citharexylum spinosum L., one new iridoid glucoside, the 7-ss-O-acetate (1) of lamiide, along with four known iridoid glucosides, lamiide (2), lamiidoside (3), duranterectoside C (4), 8-Epiloganin (5) and one known lignan glucoside (+)-lyonirenisol-3a-O-ss-D-glucopyranoside (6) were isolated. The compound structures were established by one- and two-dimensional 1H- and 13C-NMR as well as by ESI-MS spectra.

New Bisabolane-Type Sesquiterpenes from the Aerial Parts of Lippia dulcis.[Pubmed:16141591]

Chem Pharm Bull (Tokyo). 2005 Sep;53(9):1175-7.

Two new bisabolane-type sesquiterpenes, lippidulcine A (3) and epilippidulcine A (4), have been isolated from the aerial parts of Lippia dulcis TREV. along with five known flavonoids, cirsimaritin (5), salvigenin (6), eupatorin (7), 5-hydroxy-6,7,3',4'-tetramethoxyflavone (8) and 5,3'-dihydroxy-6,7,4',5'-tetramethoxyflavone (9), three known phenylethanoid glycosides, decaffeoylverbascoside (10), acteoside (11) and isoacteoside (12), and two known iridoid glucosides, 8-Epiloganin (13) and lamiide (14). Their chemical structures have been determined on the basis of spectroscopic data. Among them, 5, 7, and 9 exhibited almost the same activity as that of alpha-tocopherol, and 10-12 were identified as stronger antioxidants than alpha-tocopherol using the ferric thiocyanate method.

[Studies on chemical constituents in herb of Lamium maculatum var. kansuense (II)].[Pubmed:15724404]

Zhongguo Zhong Yao Za Zhi. 2005 Feb;30(4):272-4.

OBJECTIVE: To study the chemical constituents from Lamium maculatum var. kansuense. METHOD: The chemical constituents were isolated and repeatedly purified on silica gel column and the structures were elucidated by the NMR spectra and physico-chemical properties. RESULT: Six compounds were obtained and identified as polypodine B (I), 5-OH-8-Epiloganin (II), shlanzhiside methyl ester (III), liriodendrin (IV), quercitroside (V), uridine (VI). CONCLUSION: Compound IV was found from genus Lamium for the first time and the rest of the compounds were found from Lamium maculatum var kansuense for the first time.

Iridoid and megastigmane glycosides from Phlomis aurea.[Pubmed:11117884]

Phytochemistry. 2000 Oct;55(4):353-7.

From the leaves of Phlomis aurea, two new iridoids of unique structures named 3-epiphlomurin (1) and phlomurin (2), a new megastigmane glucoside phlomuroside (3) and a new benzyl alcohol glycoside having the structure benzyl alcohol-O-beta-xylopyranosyl-(1-->2)-beta-glucopyranoside (4) have been isolated together with four known iridoids auroside, lamiide, 8-Epiloganin and ipolamiide, two known phenolic glycosides acteoside (verbascoside) and syringin, one known phenylethanoid glycoside 2-phenylethyl-O-beta-xylopyranosyl-(1-->2)-beta-glucopyranoside, one known lignan liriodendrin and three known flavonoids chrysoeriol-7-O-beta-glucopyranoside, acacetin-7-O-beta-glucopyranoside and luteolin-7-O-beta-glucopyranoside. The structures of the isolated compounds were verified by means of mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectral analyses.

Trans-fused iridoid glycosides from Penstemon mucronatus.[Pubmed:9887533]

Phytochemistry. 1998 Dec;49(8):2413-5.

Two new trans-fused iridoid glycosides (5 alpha H)-6 alpha-8-epidihydrocornin and (5 alpha H)-6 alpha-8-hydroxy-8-Epiloganin, were isolated from Penstemon mucronatus, along with cornin, penstemoside and three hastatosides. The trans-fused iridoids are only the second and third known among over 900 described cis-fused iridoid glycosides. Two pairs of iridoids, identical except for the stereochemistry at C-8, were found. Structures were determined by spectroscopic methods.

[Studies on chemical constituents of the roots of Lantana camara].[Pubmed:1442083]

Yao Xue Xue Bao. 1992;27(7):515-21.

Six oligosaccharides (I-VI) and six iridoid glucosides (VII-XII) isolated from the ethanolic extract of Lantana camara roots were identified as stachyose (I), verbascose (II), ajugose (III), verbascotetracose (IV), alpha-D-galac-(1-[-6)-alpha-D-galac(-1](3)-6-D-gluc(V ) , alpha-D-galac-(1-6)-alpha-D-galac(-1]-(4)6-D-)gluc(VI) , theveside (VII), 8-Epiloganin (VIII), shanzhsid methyl ester (IX), theviridoside (X), lamiridoside (XI) and geniposide (XII), on the basis of spectral analysis (1H-NMR, 13C-NMR, FD-MS, GC-MS), physico-chemical constants and preparation of derivatives. V and VI were new compounds named lantanose A and lantanose B, respectively. The others were isolated from this plant for the first time.

Phenylpropanoid and iridoid glycosides from Pedicularis lasiophrys.[Pubmed:1367881]

Phytochemistry. 1992 Jan;31(1):263-6.

Two new compounds, pedicularioside E and F, were isolated from whole plants of Pedicularis lasiophrys, along with the four known compounds, verbascoside, cistanoside C, cistanoside D and 8-Epiloganin. On the basis of spectral and chemical evidence, pedicularioside E and F were identified to be 1'-O-beta-D-(3-methoxy-4-hydroxy-beta-phenyl)-ethyl-6'-O-feruloyl- alpha-L-(2-acetyl)-rhamnosyl-(1----3')-4'-acetylglucopyranoside and shanzhisin methyl ester cellobioside, respectively.

Phlinosides D and E, phenylpropanoid glycosides, and iridoids from Phlomis linearis.[Pubmed:1367797]

Phytochemistry. 1991;30(9):3073-5.

Two new phenylpropanoid glycosides, phlinosides D and E were isolated from the methanolic extract of the aerial parts of Phlomis linearis, along with the known iridoid glucosides, lamiide, ipolamiide and auroside (= 5-hydroxy-8-Epiloganin). On the basis of chemical and spectral evidence the structures of phlinosides D and E were determined as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-xylopyranosyl-(1----2)-al pha-L-rhamnopyranosyl-(1----3)-4-O-feruloyl-beta-D-glucopyranoside and 3,4-dihydroxy-beta-phenylethoxy-O-alpha-L-rhamnopyranosyl-(1----2) -alpha-L- rhamnopyranosyl-(1----3)-4-O-feruloyl-beta-D-glucopyranoside, respectively.

Hydrogenation of iridoid glucosides with exocyclic double bond.[Pubmed:17342604]

Planta Med. 1985 Oct;51(5):434-6.

Catalytic hydrogenation of two iridoids of unusual type with an exocyclic double bond, namely serrulatoloside and gardoside methyl ester, over PtO (2) catalyst to give 10-desoxypatrinoside and 8-Epiloganin, respectively, is described.

8-epiloganic acid and 7-beta-hydroxy-8-epiiridodial glucoside.[Pubmed:17396936]

Planta Med. 1982 Sep;46(1):38-41.

Two new iridoid glucosides, isolated from Linaria cymbalaria (Scrophulariaceae), are 8-epiloganic acid ( 1) and 7-beta-hydroxy-8-epiiridodial glucoside ( 2). Partial synthesis of 2 from 8-Epiloganin ( 3) has been performed.