Dimethoxybenzoic Acid Research Articles

Chemical characterization and biological activity of Molineria latifolia root extract as dermal antiaging: Isolation of natural compounds, in silico and in vitro study

Premature skin-aging is a disorder in human skin tissue caused by the effects of environmental factors. It is important to prevent and treat this disorder using natural ingredients. One of them is the Molineria latifolia plant, which is reportedly anti-aging. This study aims to characterize the chemical content of M. latifolia extract and evaluate its biological activity as a skin anti-aging. The 70% ethanol extract of M. latifolia roots was fractionated by a chromatography column using a solvent based on a gradient. The fractions obtained were evaluated for antioxidant, anti-tyrosinase, and anti-elastase activities. The active fraction was purified, and its chemical structure was characterized. The compounds were assessed for anti-aging activity in silico using 2Y9X and 3HGN proteins and continued with in vitro evaluation. The isolation results obtained six secondary metabolite compounds, namely 2,6 dimethoxy-benzoic acid (1), curculigoside-A (2), curcapital (3), syringic acid (4), 2-hydroxy-4-methoxybenzyl-2,3-dihydroxy-5-methoxybenzoate or curlatifolia-SN (5), and luteolin (6). Compound 5 is newly phenolic discovered and has not been reported in previous research. Compounds 3, 5, and 6 interact best with 2Y9X (tyrosinase) and 3HGN (elastase) proteins in silico based on the obtained binding affinity. In vitro activity shows that compounds 3, 5, and 6 have strong to very strong activity inhibiting 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, tyrosinase, and elastase. Compounds 3, 5, and 6 inhibit tyrosinase through a mixed inhibition mechanism, while elastase inhibits competitively. Compounds 3, 5, and 6 are phenolic derivatives with the best anti-aging activity, which can be used as anti-aging skin agent for future development.

An alternative synthetic strategy for (3R, 5R)-sonnerlactone and (3R, 5S)-sonnerlactone

A novel stereoselective strategy for the synthesis of both the (3R,5R)-sonnerlactone (1) and (3R,5S)-sonnerlactone (1a) was developed, which was accomplished from commercially available 2,4 dimethoxy benzoic acid and known chiral bisepoxides using allylation directed by ortho lithiation, Corey-Seebach reaction, Yamaguchi macrolactonisation and Mitsunobu reaction as key steps.

Novel zinc-2,6- dimethoxybenzoic acid complex as useful precursor for the synthesis of MWCNTs-ZnO nano-inorganic composite

The production of nanomaterials from new sources is an important topic because the diversity of the raw materials provides a variety of properties for these materials, therefore, this study involved the synthesis and characterization of a zinc complex obtained by reacting 2,6-dimethoxybenzoic acid (DMB) with zinc chloride in the presence of triethylamine as a bulk base. The structure and coordination mode of the resulting zinc complex were determined through various techniques, including FTIR, 1H NMR, elemental analysis, and molar conductivity. The findings confirmed that the 2,6-dimethoxybenzoic acid ligand acts as a bidentate ligand, coordinating through both oxygen atoms of the carboxylic group, resulting in a complex of the type [Zn(DMB)Cl]2. This complex was then used as a precursor for the synthesis of a ZnO-MWCNTs nanocomposite using ultrasound waves. The synthesized nanocomposite was characterized using SEM and XRD techniques. The results revealed the formation of small spherical clusters around the carbon nanotubes, with an average size of the spherical nanostructures measuring 11.875 nm. Moreover, the incorporation of zinc oxide nanoparticles had a positive impact on increasing the diameter of the carbon nanotubes from 3.005 nm to 21.218 nm.

The effect of Auxin IAA and sea algae extraction on oil characteristics and active compounds of (Ocimiumbasilicum L.)

In present study, Auxin (IAA) and sea algae extraction were used on Ocimiumbasilicum L. in a field in Tikrit University on 2013.Two factors were applied: A0 without spraying Auxin and A1spraying with 50 mg/L (IAA). The second factor was spraying sea algae extraction (Kelpak) in fourlevels: E0 without spraying, E1 spray of 1.5ml/L of sea algae (Kelpak), and E2 spray with 1.5 ml/L sea algae (ultrakelpa40), E3 spray 1.5+1.5ml/L mixed of sea algae (Kelpak and ultrakelpak40) together. The study designed by Randomised complete block design RCBD. Duncan’s test wasperformed to compare the medians of treatments with multi-limits at 5% possibility.
 The results showed: the treatments with 50mg/L of (IAA) and the combination treatment of 1.5+1.5 ml/L of sea algae (Kelpak and ultrakelpak40) caused a significant increase of physical properties of oil as follow: high level of specific gravity (0.902 gm/ml), high level of refractive index (1.252) and high level of oil concentration (1.021%)in compare with non treated plants with less level of specific gravity, refractive index and refractive index (0.876 gm/ml, 1.241, 0.74%) respectively. The results also showed that the treatment A1E1 significantly affected oil components and gave highest level of 2.5dimethoxybenzoic acid Ocimol(79.18), the treatment A0E3 caused highest level of Methyl eugenol (68.02), the treatment A0E2 gave highest level of Methycinammate (262.20) and Cubebene (159.88), the treatment A1E2 gave highest level of Linalool (204.99), the treatment A0E2 gave highest level of Geranyle acetate (342.61). The spraying with sea algae extract also affected those active substances as follow: the plants which treated with A1E1 gave the highest level of Caftaric acid (590.93) and Quercetin (213.17) in compare with the treatment of A1E3 that gavehighest level of Myriscetin (514.21) and highest level of both Kaempferol (916.27) and Anthraquimones (551.45), the treatment of A0E1 caused an increase in the concentrations of Rutine(477.12) and Quercetin (314.80) and Luteolin (285.09).

Occurrence of Patulin and Polyphenol Profile of Croatian Traditional and Conventional Apple Cultivars during Storage.

Apples and apple-based products are among the most consumed fruits around the world. However, they are susceptible to infection with the fungi Penicilium expansum. In addition to the reduction of apple quality, secondary metabolism of this fungus produces a mycotoxin patulin that has a negative effect on human health. Currently, there is no available research in the literature on the resistance of Croatian traditional apple cultivars to contamination with P. expansum, and consequently, on the patulin content in apples and apple juice produced from those apples. Although the mechanism of apple resistance to fungal diseases has not yet been sufficiently investigated, some studies have shown that polyphenolic compounds have some impact on fungi growth. In order to contribute with new knowledge, this research deals with monitoring the growth of P. expansum on apples, patulin detection by LC/MS-MS, determination of polyphenol profile by validated HPLC method, and determining the effect of polyphenolic compounds on fungi growth and patulin production during apple storage. The results of this study have shown that Croatian traditional apple cultivars harvested from family farm Horvatić contain higher concentration of polyphenolic compounds and higher antioxidant activity. At the same time, they showed more resistance to infection by P. expansum than conventional ones. The higher content of dihydrochalcones and flavanols encouraged the biosynthesis of patulin in examined cultivars. However, the higher content of non-flavonoids such as 2-6 dimethoxybenzoic acid, 4-hydroxycinnamic acid and chlorogenic acid leads to decrease in content of patulin. In conclusion, it seems that content of polyphenols and patulin production are correlated.

Crown ether and crown ether/K+ complex assisted DOSY NMR: A versatile tool for positional isomers identification in aqueous solution

Diffusion-ordered spectroscopy (DOSY) is a powerful and efficient technique for the analysis of complex mixtures, relying on their differential in self-diffusion coefficient. However, DOSY is often struggled to separate signals pertaining to isomeric species, especially positional isomers. Here, for the first time, we describe the novel design of 18-crown ether-6 (18C6) and 18C6/K+ complex as matrixes to discriminate and identify positional isomeric mixtures of phenylenediamine, nitroaniline, phthalic acid, dimethoxybenzoic acid, aminophthalic acid and even amino acids using 1H DOSY spectrum. The superior performance of 18C6 and 18C6/K+ complex as matrix depends on that they can interact with different components with varying binding energy as demonstrated by MMMF calculations and the DFT calculation. The methodology presented here is simple yet efficient. Moreover, the crown ether and crown ether/K+ complex provide the dual mode discrimination for both amino and carboxylic substituted positional isomers.

Synthesis and Antioxidant Activity Evaluation of New Organic Reagent 2-[2—_(5-Nitro thiazolyl)azo]-4,6-dimethoxy benzoic acid (NTADMBA)

This study concerned synthesis and characterized new organig reagent 2-[2—(5-nitro thiazolyl)azo]-6.4 dimethoxy benzoic acid (NTADMBA) and also its antioxidant, biomolecule protective. The organig reagent was characterized by FTIR, NMR and mass spectroscopy. The antioxidant tests showed the enhanced potency of E. coli bacteria. the study suggests that the organig reagent (NTADMBA) herb unequivocally is a potential source of antioxidants and could aid in alleviating oxidative stress-mediated disorders.

Synthesis Novel Organig Reagent of 2-[2—(5-Nitro thiazolyl)azo]-4,6-dimethoxy benzoic acid (NTADMBA) and Applyed it as antioxidants

This study concerned synthesis and characterized new organig reagent 2-[2—(5-nitro thiazolyl)azo]-6.4 dimethoxy benzoic acid (NTADMBA) and also its antioxidant, biomolecule protective. The organig reagent was characterized by FTIR, NMR and mass spectroscopy. The antioxidant assays showed the enhanced potency of E. coli bacteria. the study suggests that the organig reagent (NTADMBA) herb unequivocally is a potential source of antioxidants and could aid in alleviating oxidative stress-mediated disorders.

Simultaneous identification of low-molecular weight phenolic and nitrogen compounds in craft beers by HPLC-ESI-MS/MS

Phenolic and nitrogenous compounds from different styles craft beers were identified by high performance liquid chromatography and mass spectrometry in order to stratify beer samples according to their style. For this, an exploratory assessment relying on Linear Discriminant Analysis was performed. Fifty-seven phenolic compounds were reported and twelve of them were found for the first time in beer: benzoic acids, 2,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, dimethoxybenzoic acid; phenolic acid conjugates, 3-p-coumaroylquinic acid, 4-p-coumaroylquinic acid, 3-feruloylquinic acid, 4-feruloylquinic acid, 5-feruloylquinic acid; flavonoids, taxifolin hexoside, quercetin dihexoside, apigenin-6,8-dipentoside, and isofraxidin hexoside. Additionally, 11 nitrogenous compounds belonging to the phenolamide class were found. Two discriminant functions were generated and allowed a satisfactory separation among all beer styles. 3-Caffeoylquinic acid, 3-p-coumaroylquinic acid, 4-p-coumaroylquinic acid, 5-caffeoylquinic acid, coumaric acid, kaempferol-3-O-rutinoside, proanthocyanidin B dimer III and proanthocyanidin B dimer V were the compounds that showed the highest capacity of discriminate the beer styles (IPA, Lager and Weiss).

Free and Bound Phenolic Compound Content and Antioxidant Activity of Different Cultivated Blue Highland Barley Varieties from the Qinghai-Tibet Plateau.

In this study, the polyphenols composition and antioxidant properties of 12 blue highland barley varieties planted on the Qinghai-Tibet Plateau area were measured. The contents of the free, bound and total phenolic acids varied between 166.20–237.60, 170.10–240.75 and 336.29–453.94 mg of gallic acid equivalents per 100 g of dry weight (DW) blue highland barley grains, while the free and bound phenolic acids accounted for 50.09% and 49.91% of the total phenolic acids, respectively. The contents of the free, bound and total flavones varied among 20.61–25.59, 14.91–22.38 and 37.91–47.98 mg of catechin equivalents per 100 g of dry weight (DW) of blue highland barley grains, while the free and bound flavones accounted for 55.90% and 44.10% of the total flavones, respectively. The prominent phenolic compounds in the blue hulless barley grains were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, naringenin, hesperidin, rutin, (+)-catechin and quercetin. Among these, protocatechuic acid, chlorogenic acid and (+)-catechin were the major phenolic compounds in the free phenolics extract. The most abundant bound phenolics were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, benzoic acid, dimethoxybenzoic acid, naringenin, hesperidin, quercetin and rutin. The average contribution of the bound phenolic extract to the DPPH• free radical scavenging capacity was higher than 86%, that of free phenolic extract to the ABTS•+ free radical scavenging capacity was higher than 79%, and that of free phenolic (53%) to the FRAP antioxidant activity was equivalent to that of the bound phenol extract (47%). In addition, the planting environment exerts a very important influence on the polyphenol composition, content and antioxidant activity of blue highland barley. The correlation analysis showed that 2,4-hydroxybenzoic acid and protocatechuic acid were the main contributors to the DPPH• and ABTS•+ free radical scavenging capacity in the free phenolic extract, while chlorogenic acid, vanillic acid, ferulic acid and quercetin were the main contributors to the free radical scavenging capacity in the bound phenol extract. The study results show that the blue highland barley grains have rich phenolic compounds and high antioxidant activity, as well as significant varietal differences. The free and bound phenolic extracts in the blue hulless barley grains have an equivalent proportion in the total phenol, and co-exist in two forms. They can be used as a potential valuable source of natural antioxidants, and can aid in enhancing the development and daily consumption of foods relating to blue highland barley.

Antioxidant and hepatoprotective effects ofAsparagus albusleaves in carbon tetrachloride-induced liver injury rats

The antioxidant and hepatoprotective activities of hot aqueous extract from Asparagus albus (A. albus) leaf against CCl4-induced liver damage in rats were investigated. The total phenolic, flavonoid, and condensed tannin contents of hot aqueous extract from A. albus leaf were determined. The antioxidant activity of hot aqueous extract from A. albus leaf was evaluated using the antioxidant capacity, DPPH free radical-scavenging ability and reducing power assays. Different polyphenolic compounds, namely gallic acid, vanillic acid, 3,4 dimethoxybenzoic acid, catechin, rutin, and quercetin were identified. Oral administration of hot aqueous extract from A. albus leaf to male Wistar, intoxicated with CCl4, demonstrated a significant protective effect by lowering the levels of hepatic marker enzymes (aspartate and lactate transaminases) and by improving the histological architecture of the rat liver. The hot aqueous extract from A. albus leaf attenuated oxidative stress by restoring the activities of superoxide dismutase, catalase, and glutathione peroxidase. This study demonstrated that the hot aqueous extract from A. albus leaf protects rat liver from CCl4-induced injury and suggests a potential therapeutic use for A. albus plant. Practical applications The hepatoprotective effects of plant extracts are mainly related to their richness in phenolic compounds. Phenolic compounds are secondary metabolites widely found in plants, mostly represented by phenolic acids and flavonoids. The growing interest in these bioactive antioxidant components is principally due to their antioxidant potential and the association between their consumption and the prevention of some diseases. In this study, a remarkable hepatoprotective effect of the hot aqueous leaf extract obtained from Asparagus albus was detected against CCl4-induced liver injury in rat and its mechanism was related, at least in part, to its free radical scavenging and antioxidant activity on account of the presence of polyphenols.

Naturally occurring benzoic acid derivatives retard cancer cell growth by inhibiting histone deacetylases (HDAC)

ABSTRACTHistone deacetylases (HDACs), which modulate the expression of genes, are potential therapeutic targets in several cancers. Targeted inhibition of HDAC prevents the expression of oncogenes thereby help in the treatment of cancers. Hence, several pharmaceutical companies developed inhibitors of HDAC and tested them in preclinical models and in clinical trials. SAHA (suberanilohydroxamic acid) is one such HDAC inhibitor developed for treating breast and colorectal carcinomas. However, due to poor efficacy in clinical trials the utility of SAHA for treating cancers was discouraged. Similarly another HDAC inhibitor Trichostatin-A (TSA) also showed promising results in clinical trials but exhibited severe adverse effects, which dampened the interest of using this molecule for cancer treatment. Therefore, search for developing a potent HDAC inhibitor with minimal side effects still continues. Hence, in this study we have screened benzoic acid and benzoic acid derivatives with hydroxylic (-OH) groups and methoxy (-OCH3) groups for their efficacy to bind to the TSA binding site of HDAC using molecular docking studies. Molecules that showed much stronger affinity (than TSA) to HDAC were tested for inhibiting HDAC expressing cultured cancer cells. DHBA but not Dimethoxy Benzoic Acid (DMBA) inhibited HDAC activity, leading to cancer cell growth inhibition through the induction of ROS and cellular apoptosis mediated by Caspase-3. In addition, DHBA arrested cells in G2/M phase of the cell cycle and elevated the levels of sub-G0-G1 cell population. In summary, results of this study report that DHBA could be a strong HDAC inhibitor and inhibit cancer cell growth more effectively.

Assessment of the antioxidant and antiradicalic capacities in vitro of different phenolic derivatives

Introduction: The antioxidant and radical scavenging properties of some of the hydroxy phenyl derivatives such as 4-Hydroxybenzoic acid (1), 3-Hydroxy-4-methoxycinnamic acid (2), 3-(4-Hydroxy-3,5-dimethoxyphenyl)prop-2- enoic acid (Sinapic acid) (3), 4-Hydroxy-3,5-dimethoxybenzoic acid (4), 3,4-Dihydroxycinnamic acid (Caffeic acid) (5) and 5-Isopropyl-2-methylphenol (6), which are naturally present in fruits and vegetables, were investigated. Methods: The following analysis were conducted: The total antioxidant activity via the ferric thiocyanate method; 2,2’-azinobis-(3-ethylbenzothiazole-6-sulphonate) (ABTS) radical scavenging activity; superoxide anion radical (O2•-) scavenging activity; the total reduction power through potassium ferricyanide reduction method; Cupric ions (Cu2+) reduction capacity through Cuprac method; hydrogen peroxide scavenging activity and chelating activity of ferrous ions (Fe2+). Furthermore, α-tocopherol, butylatedhydroxyanisole (BHA) and quercetin were used as the reference antioxidant compounds. Results: In the comparison of initial states and the products, it’s observed that at the 50th hour the linoleic acid emulsion at 30 μg/mL concentration inhibited the lipid peroxidation by 85%, 60.7%, 69%, 45.4%, 80.4% and 31%, respectively. On the other hand, it’s observed that the linoleic acid emulsion of α-tocopherol, (BHA) and quercetin inhibited the lipid peroxidation by 62.65%, 35.84% and 34.82% respectively, at the same concentration. Conclusions: It’s found as a result of our studies that some of the phenolic compounds such as 4-Hydroxybenzoic acid (1), 3-Hydroxy-4-methoxycinnamic acid (2), 3-(4-Hydroxy-3,5-dimethoxyphenyl)prop-2-enoic acid (3), 4-Hydroxy-3,5- dimethoxybenzoic acid (4), 3,4-Dihydroxycinnamic acid (5) and 5-Isopropyl-2-methylphenol (6) which are naturally present in foods. They have higher total antioxidant activity, radical scavenging and metal chelating activities than the widely used powerful antioxidant compounds such as BHA, Quercetin and α-tocopherol.

Four new lignans from Schisandra sphenanthera

Three new 7,8-secolignans, schisandlignans A–C (1, 2, and 4), one new dibenzocyclooctadiene lignan, schisandlignan D (5), together with nine known lignans 3′,4′-dimethoxybenzoic acid (3″,4″-dimethoxyphenyl)-2-methyl-3-oxobutyl ester (3), gomisin J (6), rubrisandrin A(1b) (7), interiotherin B (8), schisantherin D (9), ( − )-machilusin (10), ganschisandrine (11), henricine A (12), and (+)-1-hydroxy pinoresinol (13), were isolated from the rattan of Schisandra sphenanthera. Their structures were determined by analysis of 1D and 2D NMR spectroscopic data.

Antifungal compounds from Melia azedarach leaves for management of Ascochyta rabiei, the cause of chickpea blight

The antifungal activity of Melia azedarach L. leaves was investigated against Ascochyta rabiei (Pass.) Lab., the cause of destructive blight disease of chickpea (Cicer arietinum L.). Bioassay guided fractionation revealed that the chloroform fraction of the methanolic extract of M. azedarach leaves was highly effective against A. rabiei. Six compounds, namely β-sitosterol (1), β-amyrin (2), ursolic acid (3), benzoic acid (4), 3,5 dimethoxybenzoic acid (5) and maesol (6) were isolated from the chloroform fraction through column chromatography. The in vitro antifungal activity of compounds 2–5 was evaluated against A. rabiei. A commercial fungicide, mancozeb, was used as a positive control. Different concentrations of mancozeb and the isolated compounds, ranging from 0.0039 to 4 mg mL−1, were used in the antifungal bioassay, and data regarding minimum inhibitory concentration (MIC) was recorded 24, 48 and 72 h after incubation. All concentrations of mancozeb inhibited the fungal spore germination at all three incubation periods. The tested compounds exhibited variable antifungal activity against the target fungal pathogens. All compounds showed their highest antifungal activity after 24 h of incubation. Compound 2 was found to be the most effective, with an MIC of 0.0156 mg mL−1, followed by compounds 3, 4 and 5, with MIC values of 0.0312, 0.25 and 0.125 mg mL−1, respectively.

Conferin, potent antioxidant and anti-inflammatory isoflavone from Caragana conferta Benth

Conferin (1), a new isoflavone, has been isolated from the ethyl acetate soluble fraction of Caragana conferta Benth. along with seven known compounds, namely biochanin A (2), p-hydroxybenzoic acid (3), 3,5- dimethoxybenzoic acid (4), ursolic acid (5), erythrodiol (6), pinoresinol (7), and syringresinol (8), reported for the first time from this species. The structure of the new isoflavone was deduced on the basis of spectroscopic studies. Compounds 1 and 2 were investigated for biological activities and showed significant anti-inflammatory activity in carrageenan induced paw edema of rats. Evaluation of antioxidant activity by the radical scavenging method indicated that compound 1 is a potent antioxidant while 2 is moderately active. It was also shown that the reducing capability of compound 2 was remarkably increased in a concentration dependent manner as compared to 1. Compound 1 showed moderate inhibitory activity against the enzyme lipoxygenase, while 2 showed weak activity.

A Novel Synthesis of Flavones from 2-Methoxybenzoic Acids

The flavones (2-phenylchromones) are widely distributed in vascular plants and have attracted a lot of attention because they possess biological activities, such as antioxidant effect, antiviral activity, and anticarcinogenic effect. The main synthetic methods known for the flavones are the cyclodehydration of 1-(2-hydroxyphenyl)-3-phenyl-1,3propanediones, the oxidative cyclization of 2'-hydroxychalcones, and synthesis via an intramolecular Wittig reaction. The rearrangement of benzoyl esters of 2'hydroxyacetophenones (Baker-Venkataraman process) and the direct benzoylation of 2'-hydroxyacetophenones with benzoyl chlorides or methyl benzoates affords 1-(2hydroxyphenyl)-3-phenyl-1,3-propanediones, which are cyclodehydrated to give flavones in acidic conditions. The treatment of 2'-hydroxychalcones which are prepared from 2'-hydroxyacetophenones and benzaldehydes in the presence of 2 equiv of lithium diisopropylamide with oxidizing agents also affords flavones at high temperature. Alternatively Wittig reaction involves the intramolecular olefination of phosphoranes obtained from triphenylphosphine and 2-acetoxyphenacyl bromides, a four step process from 2'-hydroxyacetophenones. A common feature in all these methods is that they invariably use 2'hydroxyacetophenones as the starting material. However, there are no reports of the synthesis of flavones from 2'-methoxyacetophenones. Although 1-(2-methoxyphenyl)-3-methyl-1,3-propanedione is cyclized with boiling HI to give 2-methylchromone, the scope of the reaction is not fully investigated and there are no reports on the synthesis of flavones with 2-substituted phenyl group. Furthermore, it has been reported that the condensation of 2'-methoxyacetophenone with methyl 2-methoxybenzoate using sodium or sodium hydride failed to produce the corresponding 1,3-diketone. As part of our continuing studies of flavonoids, we report that flavones can be newly synthesized in two steps via 1-(2-methoxyphenyl)-3-phenyl-1,3-propanediones from 2'-methoxyacetophenones cheaper than 2'-hydroxyacetophenones in general. 2'-Methoxyacetophenones 2 were readily prepared by the treatment of 2-methoxybenzoic acids 1 with 2 equiv of methyllithium in THF for 2 h at −78 C (Scheme 1). The reaction proceeded smoothly to give 2 free from the corresponding tertiary alcohols after acidic hydrolysis (R, R, R=H; 92%, R1=OCH3, R , R=H; 93%, R, R=H, R2=OCH3; 88%). However, the reaction of 2,6dimethoxybenzoic acid with methyllithium proceeded sluggish due to the steric effect and thus 2',6'-dimethoxyacetophenone was prepared by the treatment of N-methoxyN-methyl 2,6-dimethoxybenzamide with methyl magnesium bromide at room temperature in 75% yield. The key intermediates, 1-(2-methoxyphenyl)-3-phenyl1,3-propanediones 4, for the synthesis of flavones 5 were readily prepared by the condensation of the lithium enolates of 2 with benzoyl cyanides. To find out the optimum reagent

Benzoic Acid Derivatives in a Hypogastrurid Collembolan: Temperature-Dependent Formation and Biological Significance as Deterrents

Two phenolic acids were identified in the collembolan Ceratophysella denticulata: 3-hydroxy-4,5 dimethoxy benzoic acid and 4-hydroxy-3,5-dimethoxybenzoic acid (syringic acid). These are localized on or in the integument of the springtail, in field-collected animals, in a ratio of 47:100 (v/v). Springtails kept under different temperature regimes showed differences in production and ratio of the benzoic acid derivatives. At 20 degrees C, C. denticulata produced only syringic acid, whereas at 10 degrees C both isomers in a ratio of 100:61 (v/v) were detected. Bioassays with C. denticulata as well as with the specialized collembolan predator Stenus comma (Staphylinidae) were carried out. Staphylinid beetles topically treated with the acids try to clean their mouthparts by rubbing them on the ground significantly more often than do control beetles. Both compounds individually and as a natural mixture have deterrent effects towards the predator S. comma.

A phenolic glycoside from Hypoxis obtusa

A new phenolic glycoside was isolated from Hypoxis obtusa, together with the known compounds acuminoside, hypoxoside and nyasoside. In the new glycoside, 2,5-dihydroxybenzyl alcohol and 3-hydroxy-2,6- dimethoxybenzoic acid moieties are linked to glucose at the C-1 and C-6 positions respectively.

ChemInform Abstract: Synthesis of Monoalkyl Derivatives of 7,7,8,8‐Tetracyano‐p‐quinodimethane from 2,5‐Dimethoxybenzoic Acid.

AbstractThe dimethoxybenzoic acid (I) is converted to the 2‐alkylcyclohexanediones (III) by metal/ammonia reduction and subsequent reaction with the alkyl halides (II).