4-methoxycinnamic Acid Research Articles

New flavane gallates isolated from the leaves of Plicosepalus curviflorus and their hypoglycemic activity

Two new flavane gallates were isolated from the leaves of Plicosepalus curviflorus. The structure of the new compounds was established as 2S,3R-3,3′,4′,5,7-pentahydroxyflavane-5-O-gallate (1) and 2S,3R-3,3′,4′,5,5′,7-hexahydroxyflavane-4′,5-di-O-gallate (2), respectively. In addition, seven known compounds (−)-catechin (3), quercetin (4), lupeol (5), β-sitosterol (6), pomolic acid (7), β-sitosterol 3-O-β-d-glucopyranoside (8) and 4-methoxycinnamic acid (9) were reported for the first time from the genus Plicosepalus. Compounds 1, 2 and 3 were investigated for their hypoglycemic activity and showed significant hypoglycemic activity in Swiss Albino mice.

Isolation and identification of phytochemical constituents from Scrophularia takesimensis

Phytochemical constituents were isolated from Scrophularia takesimensis (Scrophulariaceae) using repeated chromatography and prep-HPLC. Their structures were elucidated as stigmast-5-en-3-ol (1), α-spinasterol 3-O-β-d-glucopyranoside (2), 5-hydroxypyrrolidin-2-one (3), trans-cinnamic acid (4), 4-methoxycinnamic acid (5), 2-methoxycinnamic acid (6), and 5,7-dihydroxy-4′-methoxyflavone (7) by spectroscopic analysis. All compounds were isolated for the first time from S. takesimensis and compounds 2, 3, 6, and 7 were isolated for the first time from Scrophularia species. Among them, 5,7-dihydroxy-4′-methoxyflavone (7) exhibited strong AR inhibitory activity, with an IC50 value of 4.96 μM. The content of 5,7-dihydroxy-4′-methoxyflavone (7) was measured in aerial parts of S. takesimensis, S. kakudensis and S. boreali-koreana (54.3, 25.4, and 15.0 μg/g, respectively) by HPLC. Key words: Aldose reductase inhibition, HPLC analysis, phytochemical constituent, Scrophularia takesimensis.

Complexes of the selected transition metal ions with 4-methoxycinnamic acid

In this study, 4-methoxycinnamates of Mn(II), Co(II), Ni(II), Cu(II), Cd(II), Nd(III) and Gd(III) were synthesised. From the infrared (IR) spectra analysis of complexes, sodium salt and according to the spectroscopic criteria the carboxylate groups seem to be bidentate chelating. The complexes of 4-methoxycinnamates lose the water molecules in one or two steps. The final products of their decomposition are oxides of the respective metals. The enthalpy values of dehydration process were determined. The FTIR spectra of the gas phase products indicate that the decomposition of the complexes is connected mainly with the release of molecules of water (H2O), carbon dioxide (CO2), carbon monoxide (CO), methane (CH4) and other hydrocarbons. The analysed compounds follow the Curie–Weiss law. The magnetic moment values experimentally determined change as follows: from 5.90 μ B to 6.27 μ B for Mn(II) complex, from 4.57 μ B to 4.99 μ B for Co(II) complex, from 3.68 μ B to 3.30 μ B for Ni(II) complex, from 1.87 μ B to 1.96 μ B for Cu(II) complex, from 3.06 μ B to 3.51 μ B for Nd(III) complex, and from 6.91 μ B to 6.90 μ B for Gd(III) complex.

Lipase-catalyzed synthesis of 4-methoxy cinnamoyl glycerol

Abstract Cinnamoyl esters are used as organic ultraviolet (UV) filters in sunscreens and cosmetic formulations. To avoid any possible harmful effects from chemically synthesized product, the enzymatic synthesis appears to be an excellent way to satisfy the present consumer demand for natural products. Enzymatic esterification of 4-methoxy cinnamic acid (4MCA) with glycerol was carried out in organic solvents using immobilized lipase B from Candida antarctica , in which the maximum conversion of 34% was found in isooctane at 70 °C after 24 h with 12% of enantiomeric excess. If the reaction continued for longer times (48 h) it leads to the formation of 16% of diester along with 56% of monoester. The results of enzymatic esterification were compared with reported chemical esterification and the present method was found to be superior in terms of conversion yields and priority to the formation of monoester. Synthesized monoester product was isolated and characterized by spectroscopic techniques.

Chemical constituents of Polygala tenuifolia roots and their inhibitory activity on lipopolysaccharide-induced nitric oxide production in BV2 microglia

A methanolic extract of the roots of Polygala tenuifolia (Polygalaceae) significantly attenuated nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated BV2 microglia cells. Five xanthones, 1-hydroxy-7-methoxyxanthone (1), 3,6-dihydroxy-1,2,7-trimethoxyxanthone (2), 1,3,6-trihydroxy-2,7-dimethoxyxanthone (3), 1,7-dihydroxy-2,3-dimethoxyxanthone (4) and 1,7-dihydroxy-3-methoxyxanthone (5), and five phenylpropanoids, 4-hydroxy-3-methoxypropiophenone (6), methyl 4-hydroxy-3-methoxycinnamic acid (7), 3,4,5-trimethoxycinnamic acid (8), 4-methoxycinnamic acid (9) and β-d-(3-O-sinapoyl) fructofuranosyl-α-d-(6-O-sinapoyl)glucopyranoside (10), were isolated from CHCl3 fraction using bioactivity-guided fractionation. Among these compounds, compounds 1, 2, 4, 5 and 7 showed significant inhibitory effects on LPS-induced NO production in BV2 microglia cells at the concentration ranging from 10.0 to 100.0 μM.

Natural products modulate Shigella–host-cell interaction

This study focused on identifying possible new options derived from natural sources for the treatment of bacterial infections. Several natural products were investigated for their potential in modulating Shigella-host-cell interactions. The proliferation of Shigella sonnei was effectively inhibited inside HEp-2 cells in the presence of 4-methoxycinnamic acid and propolin D. Propolin D also significantly reduced the apoptosis of infected macrophage-like U937 cells and moderately reduced the secretion of interleukin (IL)-1β and IL-18, which probably resulted from the inhibition of invasion plasmid antigen B secretion by this compound. Further characterization showed that propolin D did not prevent escape of Shigella from phagocytic vacuoles, as evidenced by actin-based motility and by the fact that addition of chloroquine did not further reduce the number of intracellular c.f.u. The role of propolin D in modulating autophagy could not be established under the experimental conditions used. As these compounds had no direct anti-Shigella activity in vitro, it was concluded that these compounds modulated Shigella-host-cell interactions by targeting yet-to-be defined mechanisms that provide benefits to host cells.

Influence of Different Ligand Isomers on the Growth of Lanthanide Phosphate Nanoparticles

The steric position of the methoxy group in different isomers of methoxycinnamic acid ligands is observed to have a strong impact on the particle growth of lanthanide phosphate nanoparticles. Very small nanoparticles with a mean size of less than 4 nm are obtained for all phosphates from lanthanum to europium, if 3-methoxycinnamic acid or trans-4-methoxycinnamic acid are used as ligands or if these methoxy isomers are replaced by cinnamic acid or phenylpropionic acid. However, if trans-2-methoxycinnamic acid is employed in the synthesis, anisotropic particle growth along the [200] axis is observed, yielding elongated nanoparticles with an average length of up to 25 nm. Our results indicate that in all cases small nanoparticles are formed first at early stages of the synthesis and that these particles grow to larger particles only if trans-2-methoxycinnamic acid is used as the ligand. We assume that the position of the methoxy group in trans-2-methoxycinnamic acid leads to an easier displacement or removal of these ligands from the surface of the small particles, resulting in a less effective shielding of the particles against particle growth.

Therapeutic window for ferulic acid protection against noise-induced hearing loss in the guinea pig

Conclusion: Our results are in agreement with the general idea that natural antioxidants achieve their best cytoprotective capacity if given before and soon after the stressor. Objective: We focused on ferulic acid (FA, 4-hydroxy 3-methoxycinnamic acid), a phenolic compound that is known to exhibit antioxidant properties. Our study was designed to evaluate the effectiveness of FA for different schedules of treatment to establish the ‘therapeutic window’ for FA protection. Methods: Guinea pigs were exposed to acoustic trauma (6 kHz at 120 dB for 60 min) and received a total dose of 600 mg/kg of FA. Group I, noise control; group II, noise + FA (150 mg/kg) for 4 days starting 24 h post exposure; group III, noise + FA (60 mg/kg) 1 h before and 9 days post exposure; group IV, noise + FA (60 mg/kg) given 3 days before and 7 days post exposure; group V, noise + FA (150 mg/kg) 1 h before and 3 days post noise exposure. Auditory brainstem response (ABR) test and immunohistochemical and morphological studies were performed. Results: Group V had significantly decreased noise-induced hearing loss at day 21 from noise exposure. The improvement of auditory function by FA was paralleled by a significant reduction in oxidative stress marker. The other schedules of drug administration showed a minor degree of protection.

Chemical constituents of the aerial part of Atractylodes macrocephala

To investigate the chemical constituents from the aerial part of Atractylodes macrocephala. The constituents were isolated and purified by repeated column chromatography on silica gel, Sephadex LH-20 and ODS. Their structures were identified by physicochemical properties and spectrum analysis. Fourteen compounds were isolated and identified as atractylenolide I-III (1-3), 2-[(2E) -3, 7-dimethyl-2, 6-octadienyl]-6-methyl-2, 5-cyclohexadiene-1, 4-dione(4), 2, 6-dimethoxyphenol (5), scopoletin (6), 4-methoxycinnamic acid (7), caffeic acid (8), ferulic acid (9) protocatechuic acid (10), 3-hydroxy-1-(4-hydroxy-3- methoxyphenyl) propan-1-one (11), dictamnoside A (12), syringin (13), D-mannitol (14). All the compounds were isolated from the aerial part of A. macrocephala for the first time and compounds 4, 5, 7-12, 14 were isolated from this species for the first time.

Rapid Separation and Determination of Five Phenolic Acids in Tobacco by CE

A rapid and practical capillary electrophoresis (CE) method was developed for the determination of 2-methoxycinnamic acid, 4-hydroxyl-3-methoxycinnamic acid, vanillic acid, salicylic acid and 3,4-dihydroxybenzoic acid in tobacco samples. Five phenolic acids were Soxhlet extracted with NaOH solution following solid phase extraction (SPE) clean-up. The CE method was optimized with the running buffer of 25 mmol L−1 sodium borate (pH 9.3), and the applied separation voltage of +25 kV over a capillary of 75 μm i.d. × 375 μm o.d. × 48.5 cm (40 cm to the detector window), which gave a baseline separation of five phenolic acids within about 7 min. Under the detection at 205 nm, the method gave the limits of quantification (S/N = 10) at about 1.6–3.0 μg g−1 for five phenolic acids, whereas the overall recoveries were >80%. The proposed method has been successfully applied to measure five phenolic acids in ten actual tobacco samples, and their contents were obtained and evaluated.

Pressurized liquid extraction and GC‐MS analysis for simultaneous determination of seven components in Cinnamomum cassia and the effect of sample preparation

A pressurized liquid extraction and GC-MS method was developed for simultaneous quantitative determination of the seven components, including cinnamaldehyde, copaene, cinnamic acid, coumarin, 2-methoxycinnamaldehyde, 2-methoxycinnamic acid and safrole in Cinnamomum cassia. The results showed that methanol and ethanol was not available for extraction of cinnamaldehyde and 2-methoxycinnamaldehyde due to aldol reaction. The developed method was validated to be sensitive, accurate and simple, and was successfully employed for the analysis of 15 samples of C. cassia. The contents of the investigated components were significantly variant and cinnamaldehyde is the most abundant compound, but safrole was not detected in all samples.

SYNTHESIS OF p-METHOXY-CYNNAMIL- p-METOXYCINAMATE FROM ETHYL p-METHOXYCINAMAT WAS ISOLATED FROM DRIED RHIZOME Kaempferia Galanga L AS SUNSCREEN COMPOUND

Synthesis of p-methoxy-cynnamil-p-methoxy-cinnamate, (PMS)2O from ethyl-p-methoxy-cinnamate (EPMS) from dry rhizome of kaempferia galanga L as sunscreen compound have been done. Isolation of EPMS was done by percholation using ethanol 96 % and recrystallitation using methanol to have 2.2 % yield. Hydrolysis of EPMS using alcoholic KOH resulted methoxycinnamic acid (APMS) of 90.26 % yield. Reduction EPMS using lithium aluminium hydride in dry ether would give p-methoxycinnamoyl alcohol (PMS-OH) of 41.98 % yield. Then reaction of p-methoxycinnamoyl chloride (PMS-Cl) and PMS-OH in chloroform would produce p-methoxycinnamoyl p-methoxycinnamate ((PMS)2O) of 1.77 % yield. All compound were identified by TLC and several spectrometry methodes i.e. U.V Vis, IR, 1H-NMR and GC-MS Keywords: esther cinnamate, sunscreen, Kaempferia galanga.

ChemInform Abstract: A Strategy for the Asymmetric Aminohomologation of α,β-Dihydroxy Aldehydes: Application to the Synthesis of the Southwest Tripeptide Segment of Echinocandin B.

The synthesis of the (2S,3S,4S)-3,4-dihydroxyhomotyrosine amino acid segment, present in echinocandin B, in its activated form ready for peptide coupling is described. The key steps of the approach are the enantioselective AD reaction of 4-methoxycinnamic acid methyl ester, a completely diastereoselective [2 + 2] hydroxyketene−imine cycloaddition, and the TEMPO-assisted cycloexpansion of the resulting 3-hydroxy β-lactam to the corresponding α-amino acid N-carboxy anhydride (NCA). The smooth opening of the latter upon treatment with l-Thr(OSitBuPh2)OMe and further acylation with the N-Cbz protected l-4-tert-butyldiphenylsilyloxy proline rendered the southwest portion of echinocandin B.

Photo-Sensitive Polyimide Containing Methoxy Cinnamate Derivatives on Photo-Alignment of Liquid Crystal

Photosensitive polyimide containing methoxy cinnamate derivatives as a photo-alignment layer is investigated. 4-Methoxy cinnamic acid, 2-methoxy cinnamic acid and 2,5-dimethoxy cinnamic acid were irradiated and the absorption spectra were obtained with irradiation time. 4-methoxy cinnamic acid and 2-methoxy cinnamic acid are observed isosbestic points at 258 nm and 250 nm, respectively and 2,5-dimethoxy cinnamic acid has no isosbestic pioint. 2-Methoxy cinnamic acid was most photosensitive with 30 sec irradiation time. Polyimide containing methoxy cinnamte derivatives was synthesized and the anisotropy of alignment layer was induced by irradiation linearly polarized UV (LPUV). UV irradiation of a film a of polyimide with 2-methoxy cinnamate proceeded predominantly by the photo-isomerizaiton.

Synthesis and photostability of methoxycinnamic acid modified cyclodextrins

Various cyclodextrins, alpha, beta and gamma, were esterified with 4-methoxy-, 2,4,5- and 2,4,6-trimethoxycinnamic acids. Upon esterification with β-cyclodextrin, the photostability of 2,4,5-trimethoxycinnamate increased while no improvement was observed for 4-methoxycinnamate and 2,4,6-trimethoxycinnamate. However, increase in the photostability of 4-methoxycinnamoyl moiety could be observed when esterified with α-CD and that of 2,4,6-trimethoxycinnamoyl moiety could be observed after being esterified with γ-CD. These photostability data together with the 2D NMR analyses indicated that the 4-methoxycinnamoyl, 2,4,5-trimethoxycinnamoyl and 2,4,6-trimethoxy cinnamoyl moieties could enter the α-CD, the β-CD, and the γ-CD cavities, respectively.

O-Methylation of phenylphenalenone phytoalexins in Musa acuminata and Wachendorfia thyrsiflora

Biosynthetic O-methylation at various sites along the backbone of inducible phenylphenalenones in Musaacuminata var. "Williams" (Musaceae) and Wachendorfiathyrsiflora (Haemodoraceae) was investigated using 13C-labelled precursors. The inducibility of O-methylated metabolites was demonstrated in both species and the origin of methoxyl group from [methyl-13C]L-methionine was confirmed. In addition to known phenylphenalenones, a methoxylated metabolite, 4-(4-hydroxy-3-methoxy-phenyl)-benzo[de]isochromene-1,3-dione, was detected and its structure elucidated mainly by NMR spectroscopic techniques. The experiments were used to discriminate methionine-derived and artificial methoxy groups formed during methanolic extraction. Finally, demethylation of 4'-methoxycinnamic acid and subsequent conversion to 3',4'-methylenedioxycinnamic acid was demonstrated in M.acuminata.

Polyphenol levels in two cotton (Gossypium hirsutum L.) callus cultures

We study the production of polyphenols by callus cultures from two cultivars of cotton (Gossypium hirsutum L.). Coker 312 produces the best calli and has embryogenic potential contrary to that of R405-2000, which is non- embryogenic. There is a relationship between the level of phenolic compounds and the callus cultures. Callogenesis in Coker 312 is highly correlated to a higher content of catechin, caffeic acid, ferulic acid, rutin, o—coumaric acid and salicylic acid. On the other hand, the cinnamic acid derivates (trans-cinnamic, cis and trans—methoxycinnamic acids) found in high amounts in R405-2000 calli could have a negative influence on the induction of cotton callogenesis.

Efficient Synthesis and Characterization of New Photoactive Dextran Esters Showing Nanosphere Formation

Different types of photoactive dextran derivatives with high degree of substitution were prepared by an efficient and mild esterification of the biopolymer with 2-methoxycinnamic acid, [(4-methyl-2-oxo-2H-chromen-7-yl)oxy]acetic acid, and azobenzene-4-carboxylic acid via in situ activation of the carboxylic acid groups with N,N'-carbonyldiimidazole. The structures of the novel dextran esters were evaluated by means of NMR spectroscopy applying the perpropionylated samples. Perpropionylation yields samples soluble in chloroform and acetonitrile that are very useful solvents not only for NMR but also for UV-vis spectroscopic studies. The photochemistry was studied by NMR and UV-vis spectroscopy in the dissolved state and the changes observed may be used to control the properties. The photoactive dextran esters form spherical nanoparticles of a size below 200 nm that are of interest in the design of smart materials.

Oxidation of cinnamic acid derivatives: A pulse radiolysis and theoretical study

Second order rate constants in the range of ( k = 1.6–4.5) × 10 9 dm 3 mol −1 s −1 were obtained for the OH induced oxidation of nitro- and methoxycinnamic acid derivatives in neutral solutions using pulse radiolysis. The transient absorption spectra exhibited a broad peak around 360–410 nm in o-methoxy, o- and p-nitrocinnamates or two peaks around 310–330 and 370–410 nm in other isomers. Quantum chemical calculations revealed that addition of OH to olefinic moiety yielded considerably more stable structures than ring addition products and the para system among the latter is the most stable. Spin density analysis suggested that olefinic adducts retained the aromaticity in contrast to its loss in ring OH adducts. An excellent linear correlation between the relative stabilities of the OH adducts (after accounting for the aromatic stabilization in olefinic adducts) and the maximum S d values is also obtained.

Insulin‐Secretagogue Activity of p‐Methoxycinnamic Acid in Rats, Perfused Rat Pancreas and Pancreatic β‐Cell Line

This study investigated the effect of p-methoxycinnamic acid (p-MCA) on plasma glucose and insulin concentrations in normal and streptozotocin-induced diabetic rats. In both fasting and glucose-loading conditions, an oral administration of p-MCA (40-100 mg/kg) significantly decreased plasma glucose and also increased plasma insulin concentrations in both normal and diabetic rats. The onset of the p-MCA-induced antihyperglycaemia/hypoglycaemia was observed at 1 hr after administration. In perfused rat pancreas, p-MCA (10-100 microM) stimulated insulin secretion about 1.4- and 3.1-fold of basal-control group. In addition, p-MCA (10 microM) enhanced glucose-induced insulin secretion. Moreover, p-MCA stimulated insulin secretion and increased intracellular Ca(2+) concentration ([Ca(2+)](i)) in insulinoma-1 cells. Taken together, our findings suggested that p-MCA exerted antihyperglycaemic/hypoglycaemic effect by stimulating insulin secretion from pancreas and could be developed into a new potential for therapeutic agent used in type 2 diabetic patients.