Antinociceptive substances from Incarvillea delavayi

Monoterpene Alkaloids from Incarvillea delavayi Bureau et Franchet and Their Inhibition against LPS Induced NO Production in BV2 Cells

Three new monoterpene alkaloids, delavatines C-E (1-3), along with five known ones (4-8), were separated from the whole plants of Incarvillea delavayi. All compounds were deduced by interpretation of comprehensive NMR spectral data and X-Ray single crystal diffraction, in combination with a quantum chemical calculation of NMR chemical shift coupled with an advanced statistical procedure DP4+. Compounds 1-8 were assessed NO suppressive effect in LPS-stimulated BV2 microglia cells. Compounds 2, 3, 6, and 8 exhibited significant inhibition against NO production in LPS-induced BV2 cells with IC₅₀ values of 25.62, 17.29, 19.94 and 23.88 μM, stronger than or comparable to the positive control (AG) with IC₅₀ value of 26.13 μM.

Two bi-functional cytochrome P450 CYP72 enzymes from olive (Olea europaea) catalyze the oxidative C-C bond cleavage in the biosynthesis of secoxy-iridoids - flavor and quality determinants in olive oil

Olive (Olea europaea) is an important crop in Europe, with high cultural, economic and nutritional significance. Olive oil flavor and quality depend on phenolic secoiridoids, but the biosynthetic pathway of these iridoids remains largely uncharacterized. We discovered two bifunctional cytochrome P450 enzymes, catalyzing the rare oxidative C-C bond cleavage of 7-epi-loganin to produce oleoside methyl ester (OeOMES) and secoxyloganin (OeSXS), both through a ketologanin intermediary. Although these enzymes are homologous to the previously reported Catharanthus roseus secologanin synthase (CrSLS), the substrate and product profiles differ. Biochemical assays provided mechanistic insights into the two-step OeOMES and CrSLS reactions. Model-guided mutations of OeOMES changed the product profile in a predictable manner, revealing insights into the molecular basis for this change in product specificity. Our results suggest that, in contrast to published hypotheses, in planta production of secoxy-iridoids is secologanin-independent. Notably, sequence data of cultivated and wild olives point to a relation between domestication and OeOMES expression. Thus, the discovery of this key biosynthetic gene suggests a link between domestication and secondary metabolism, and could potentially be used as a genetic marker to guide next-generation breeding programs.

Iridoid glucosides from Wendlandia ligustroides (Boiss. &Hohen.) Blakelock

Eight iridoid glucosides were reported from the aerial parts of Wendlandia ligustroides. 10-deoxygeniposidic acid (1), 7-deoxygardoside (2), geniposidic acid (3), 7-deoxy-8-epi-loganic acid (4), deacetyl-daphylloside (5), scandoside methyl ester (6), 6-O-methyl-deacetyl-daphylloside (7), 6-O-methyl-scandoside methyl ester (8). Compounds 3 - 8 were isolated as a pure form while 1 and 2 as a mixture. The structures of the compounds 1 - 8 were established by spectroscopic methods including 1D-NMR (1H NMR, 13C NMR, DEPT-135), 2D-NMR (COSY, NOESY, HSQC, HMBC) and HRMS.

Phytochemical Analysis, Antioxidant and Analgesic Activities of Incarvillea compacta Maxim from the Tibetan Plateau

Incarvillea compacta Maxim is a traditional Tibetan plant widely used to treat rheumatic pain and bruises. We conducted qualitative analyses by liquid chromatography-mass spectrometry and quantitative analyses of the total phenols, flavonoids, and alkaloids content of different extracts of I. compacta Maxim. Antioxidant and analgesic activity were analyzed. The results showed that the methanol extract had the highest content of the various ingredients. A total of 25 constituents were identified, of which compounds 1–23 were found for the first time in this plant. The water extract had the highest capacity to clear free radicals in the antioxidant test. The water extract had dose-dependent analgesic effects in the first and second phase in a formalin test. The latency of pain from a hot-plate test was augmented by the water extract when the dose was greater than or equal to 30 g/kg. The water extract significantly decreased the amount of writhing in a dose-dependent manner compared with the control group in the acetic acid-induced writhing test. These results showed that I. compacta Maxim is a new antioxidant and analgesic agent, and this study provides information on its ingredients for further study.

Delavatine A, a structurally unusual cyclopenta[de]isoquinoline alkaloid from Incarvillea delavayi

Delavatine A, a cytotoxic alkaloid with a unique cyclopenta[de]isoquinoline core, was isolated from I. delavayi.

Triterpenoid saponins and monoterpenoid glycosides from Incarvillea delavayi

Two new triterpenoid saponins, incarvillosides A (1) and B (2), and two new monoterpenoid glycosides, incarvillosides C (3) and D (4), were isolated from the high-polarity fraction of the whole plant of Incarvillea delavayi. By means of spectroscopic data and chemical degradation, the structures were established as (3beta,21beta)-3,19,21,23-tetrahydroxyurs-12-en-28-oic acid 28-O-beta-d-glucopyranoside (1), (2beta,3beta,19alpha)-2,3,19,23-tetrahydroxyolean-12-en-28-oic acid 28-O-beta-d-glucopyranoside (2), (2S,6R)-2,6-dimethyl-1,8-octanediol 1-O-beta-d-glucopyranoside (3), and (2S,6R)-2,6-dimethyl-1,8-octanediol 8-O-beta-d-glucopyranoside (4).

Efficient Synthesis of Fused Bicyclic Glutarimides. Its Application to (±)-Alloyohimbane and Louisianin D

[reaction: see text] The reaction of alpha-sulfonyl acetamide 1 with various cyclic unsaturated esters 2 to fused bicyclic glutarimides is reported. Syntheses of (+/-)-alloyohimbane (4) and louisianin D (5) have been accomplished.

NMR assignments and single-crystal X-ray diffraction analysis of deoxyloganic acid

7-Deoxyloganic acid (1), citrusin C (2), 3,4-dihydroxyl benzoic acid (3) and (E)-caffeic acid (4) were isolated from the water-soluble fraction of ethanol extracts of Morina nepalensis var. alba Hand.-Mazz. and their structures were determined on the basis of spectroscopic evidence. The total assignments of 1H and 13C NMR spectra of 1 in solvents CD3OD, D2O and CDCl3 were reported, in addition to the single-crystal X-ray diffraction analysis of its tetraacetate 1a. All compounds were obtained from Morina genus for the first time.

Novel ceramides and a new glucoceramide from the roots of Incarvillea arguta

Novel ceramides, rel-(3S,4S,5S)-3-[(2R)-2-hydroxycosanoyl-hexacosanoylamino]-4-hydroxy-5-[(4Z)-tetradecane-4-ene]-2,3,4,5-tetrahydrofuran (1a-g), and a new glucoceramide, 1-O-beta-D-glucopyranosyl-(2S,3S,4R,8E)-2-[(2R)-2-hydroxytetracosanoylamino]-1,3,4-octodecanetriol-8-ene (2) were isolated from the aqueous ethanolic extract of the roots of Incarvillea arguta, together with eight known compounds: beta-sitosterol (3), oleanolic acid (4), ursolic acid (5), piperin (6), maslinic acid (7), beta-sitosterol 6'-O-acyl-beta-D-glucopyranoside (8), 8-epideoxyloganic acid (9), and plantarenaloside (10). Their structures were elucidated on the basis of spectral data including IR, MS, NMR [1H NMR, 13C NMR (distortionless enhancement by polarization transfer), 1H-1H COSY, heteronuclear multiple-quantum coherence, and heteronuclear multiple-bond coherence correlations]. The relative configurations were established by nuclear Overhauser effect spectroscopy experiments and by comparison of the NMR spectral data and coupling constants with those already reported in the literature.

Hetero [6+3] cycloaddition of fulvenes with N-alkylidene glycine esters: a facile synthesis of the delavayine and incarvillateine framework

[reaction: see text] In contrast to the [3+2] or [4+3] cycloaddition of N-metalated azomethine ylides and various alkenes, N-benzylidene glycine ethyl ester reacts with fulvenes to give the hetero [6+3] cycloaddition adducts with high stereoselectivity, constituting an efficient and novel route to [2]pyrindines.