Nitrophenylacetic Acid Research Articles

Cobalt-catalyzed decarboxylative difluoroalkylation of nitrophenylacetic acid salts

The selective installation of fluorine-containing groups adjacent to sterically hindered alkyl groups has been utilized for the synthesis and derivatization of biologically active molecules.

STIMULATION OF GROWTH AND OIL PRODUCTION IN CUMIN PLANT

A pot experiment was carried out during two successive seasons (2017/ 2018 and 2018/2019) at Medicinal and Aromatic Plants Research Department in Dokki. The aim of this work was to study the effect of foliar application of phenylalanine (Phe) and p -nitro phenylacetic acid (PNPAA) each of them alone at (0, 50,100 and 150 ppm) on cumin (Cuminum cyminum L.) plant growth, fruits yield, volatile oil production and its major chemical constituents. In general results indicated that, the foliar application of phenylalanine or p-nitrophenylacetic acid significantly increased vegetative growth expressed as (plant height, number of branches per plant) and produced higher fruits yield (g)/plant as well as volatile oil percentage and oil yield compared with control in the two seasons. Moreover, the highest values were obtained from phenylalanine or p-nitrophenylacetic acid at 150 ppm. Cumin plants showed more effective response to p-nitrophenylacetic acid (PNPAA) than phenylalanine (Phe). As for GLC analysis, the results showed that in general the highest percentage of p -menth-1-en7-ol and cumin aldehyde (p -isopropylbenzaldehyde) the main constituents in the volatile oil achieved with the treatment p-nitrophenylacetic acid at 150 ppm. The high concentration of phenylalanine and p-nitrophenylacetic acid (150 ppm) had significant increments in total phenols, total flavonoids and antioxidant activity compared with control. There was a significant increase in phenylalanine ammonia-lyase (PAL) activity compared to control. Also, there was an increment in IAA, GA3 and low level of ABA. It was observed that p -nitrophenylacetic acid (150 ppm) was superior to phenylalanine (150 ppm) in all afore mentioned characters

On-demand guest release from MOF-5 sealed with nitrophenylacetic acid photocapping groups.

Recently, we demonstrated that triphenylacetic acid could be used to seal dye molecules within MOF-5, but guest release required the digestion of the framework by treatment with acid. We prepared the sterically bulky photocapping group [bis-(3-nitro-benzyl)-amino]-(3-nitro-phenyl)-acetic acid (PC1) that can prevent crystal violet dye diffusion from inside MOF-5 until removed by photolysis.

Self-healing dyes for super-resolution fluorescence microscopy

In recent years, optical microscopy techniques have emerged that allow optical imaging at unprecedented resolution beyond the diffraction limit. These techniques exploit photostabilizing buffers to enable photoswitching and/or the enhancement of fluorophore brightness and stability. A major drawback with the use of photostabilizing buffers, however, is that they cannot be used in live cell imaging. In this paper, we tested the performance of self-healing organic fluorophores, which undergo intramolecular photostabilization, in super-resolution microscopy examining both targeted (stimulated emission depletion (STED) microscopy) and stochastic readout (stochastic optical reconstruction microscopy (STORM)). The overall goal of the study was to identify dyes and conditions that lead to improved spatial and temporal resolution of both techniques without the need for mixtures of photostabilizing agents in the imaging buffer. As a result of previously shown superior performance, we identified an ATTO647N-photostabilizer conjugate as a potential candidate for STED microscopy. We have here characterized the photostability and resulting performance of this nitrophenylalanine (NPA) conjugate of ATTO647N on oligonucleotides in STED microscopy. We found that the superior photophysical performance resulted in optimal STED imaging and demonstrated that single-molecule fluorescent transients of individual fluorophores can be obtained with both the excitation- and STED-laser. In similar experiments, we also tested a nitrophenylacetic acid conjugate of STAR635P, another frequently used dye in STED microscopy, and present a characterization of its photophysical properties. Finally, we performed an analysis of the photoswitching kinetics of self-healing Cy5 dyes (containing trolox, cyclooctatetraene and NPA-based stabilizers) in the presence of Tris(2-carboxyethyl)phosphine and cysteamine, which are typically used in STORM microscopy. In line with previous work, we found that intramolecular photostabilization strongly influences photoswitching kinetics and requires careful attention when designing STORM-experiments. In summary, this contribution explores the possibilities and limitations of self-healing dyes in super-resolution microscopy of differing modalities.

ChemInform Abstract: Synthesis of Novel Fluorescent 2‐{4‐[1‐(Pyridine‐2‐yl)‐1H‐pyrazol‐3‐yl]phenyl}‐2H‐naphtho[1,2‐d] [1,2,3]triazolyl Derivatives and Evaluation of Their Thermal and Photophysical Properties.

AbstractThree title derivatives (IX), are synthesized in 9 steps from phenyl acetonitrile (I) via Vilsmeier‐Haack formylation of nitrophenylacetic acid (II), pyrazole ring construction with dialdehyde (V) and hydrazinopyridine (VI), and coupling of the diazotized amino compound (VII) with sulfonic acid substituted naphthylamines (VIII).

Bisannulation of 2,3‐Dichloro‐1,4‐naphthoquinone with o‐Nitrophenylacetic Acid Derivatives: A Succinct Synthesis of the ABCD Ring System of Alpkinidine

AbstractThree bisannulation strategies have been used to rapidly construct pentacyclic benzo‐fused pyrrolo[4,3,2‐mn]acridines, similar to several biologically active natural products. The key steps involve Michael substitution of 2,3‐dichloro‐1,4‐naphthoquinone with o‐nitrophenylacetic acid derivatives, followed by domino amino‐Michael substitutions/cyclisations. The most efficient of these syntheses provided a model compound (1) including the ABCD ring‐system of alpkinidine, in just three steps and 55 % overall yield.

Efficient photodecarboxylation of 3- and 4-acetylphenylacetic acids in aqueous solution

The photochemistry of 3- and 4-acetylphenylacetic acids (6 and 7) has been studied in aqueous solution. This work is a continuation of research efforts aimed at understanding the structural effects on the efficacy for benzyl carbanion photogeneration via photodecarboxylation. The nitro group (at the 3- and 4-positions) is known to be an exceptionally good activating group on the benzene ring — because of its enhanced electron-withdrawing effect in the excited triplet state — for photodecarboxylation and the related photo-retro-aldol type process. It is shown in this work that the acetyl group is an equally good activating group for the photodecarboxylation. Thus, the photochemistry of 6 and 7 parallels much of what was observed for the corresponding nitrophenylacetic acids 1 and 2. Both 6 and 7 photodecarboxylate efficiently (Φd = 0.60 and 0.22, respectively, at pH 7) via the carboxylate form, to give observable (by laser flash photolysis) benzyl carbanion or related intermediates. The meta isomer 6 displays an acid-catalyzed pathway for photodecarboxylation at pH < 3 and along with its enhanced overall reactivity, is consistent with a meta effect of the acetyl group. Triplet state reactivity is inferred from sensitization and laser flash photolysis experiments. Based on the results of this work, the acetyl group may now be viewed as an "enhanced" electron-withdrawing group (in the excited state) when attached to a benzene ring (i.e., in acetophenone derivatives) that is capable of inducing ionic reactions, which is not the traditional photochemistry that is expected from such compounds.Key words: photodecarboxylation, acid catalysis, acetophenone, photogenerated carbanion, enol, enolate.

New Approach to the Synthesis of 3-Arylcoumarins. Reaction of 3-Acyl- and 3-Ethoxycarbonylcoumarins with Hydrazide of p -Nitrophenylacetic Acid

New Approach to the Synthesis of 3-Arylcoumarins. Reaction of 3-Acyl- and 3-Ethoxycarbonylcoumarins with Hydrazide of p -Nitrophenylacetic Acid

Synthesis, molecular modeling, and structure-activity relationship of benzophenone-based CAAX-peptidomimetic farnesyltransferase inhibitors.

Because of the involvement of farnesylated proteins in oncogenesis, inhibition of the protein-modifying enzyme farnesyltransferase is considered a major emerging strategy in cancer therapy. Here, we describe the structure-activity relationship of a novel class of CAAX-peptidomimetic farnesyltransferase inhibitors based on the benzophenone scaffold. 4'-Methyl, 4'-chloro, 4'-bromo, and 4'-nitrophenylacetic acid as substituents at the 2-amino group of the benzophenone core structure yield farnesyltransferase inhibitors active in the nanomolar range. Using diphenylacetic acid in this position further improves activity. SEAL superimposition of inhibitor 12a to the enzyme-bound conformation of a CAAX-peptide shows a markedly good resemblance of the molecular properties of the peptide. FlexX docking of 12a confirms the good fit of the molecule into the peptide binding site of farnesyltransferase. The novel benzophenone-based AAX-peptidomimetic substructure described here will be useful for the design of some novel types of farnesyltransferase inhibitors.

Selective reduction of the aromatic nitro group with retention of the nitrate group

Selective reduction of a nitro group whilst retaining the ONO2 group has been carried out for the first time in the hydrogenation of nitrates of N-ethanolamidesp-nitrobenzoic and nitrophenylacetic acids.

A universal antibody-derived targeting agent.

We report bacterial expression of a single-chain antibody (ScFv) reactive against the haptens 4-hydroxy-3 nitrophenylacetic acid (NP) and 4-hydroxy-3-iodo-5-nitrophenylacetic acid (NIP) that is suitable for targeting to mammalian cells in vitro in a novel two-step targeting strategy. Hapten-derivatized primary antibodies of known specificity, bound to target cells, can capture the ScFv. Specificity resides in the interaction of the primary targeting antibody with the target and the interaction of the ScFv for NP/NIP, since the ScFv does not bind cells and nonderivatized antibodies bound at cells cannot capture the ScFv. The ScFv described here can therefore be considered as a universal agent for delivery of drugs, toxins, or radionuclides to any cell type for which a previously characterized antibody exists.

Methyl (2,5-dihydroxy-3-nitrophenyl) acetate from Pseudomonas syringae pv. papulans

A new trisubstituted derivative of phenylacetic acid methyl ester was isolated from a Pseudomonas syringae pv. papulans strain culture. It was characterized as the methyl ester of 2′,5′-dihydroxy-3′-nitrophenylacetic acid by spectral studies of the metabolite and the corresponding diacetylderivative. The new metabolite modulates the growth of tomato seedlings.

Probes for narcotic receptor mediated phenomena. 17. Synthesis and evaluation of a series of trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzeneacetamide (U50,488) related isothiocyanate derivatives as opioid receptor affinity ligands

A series of U50,488 related isothiocyanates was synthesized from enantiomerically pure (S,S)-(+)-trans-2-pyrrolidinyl-N-methylcyclohexylamine [(+)-7] and (R,R)-(-)-trans-2-pyrrolidinyl-N-methylcyclohexylamine [(-)-7]. DCC coupling of (+)- and (-)-7 with nitrophenylacetic acids followed by catalytic hydrogenation and treatment with thiophosgene afforded a series of six isomeric aryl isothiocyanate analogues of U50,488. Similarly, DCC coupling of (+)- and (-)-7 with (+)- and (-)-N-t-Boc-protected phenylglycines afforded four isomeric alkyl isothiocyanates. Evaluation of the isothiocyanates for their capacity to produce wash-resistant inhibition of mu, delta, and kappa sites in vitro was performed using rat and guinea pig brain membranes. None of the compounds was able to irreversibly inhibit binding of [3H]bremazocine to guinea pig and rat brain membranes (depleted of functional mu and delta receptors by pretreatment with acylating agents BIT and FIT). However, (1S,2S)-trans-2-isothiocyanato-N-methyl-N-[2- (1-pyrrolidinyl)cyclohexyl]benzeneacetamide [(-)-1] was able to specifically and irreversibly inhibit kappa receptors labeled by [3H]-U69,593: Incubation of rat brain membranes for 60 min at 25 degrees C with 1 microM of (-)-1 resulted in a wash-resistant reduction of the binding to 11.2 +/- 2.5% of the control. Binding analysis revealed the wash-resistant reduction in [3H]-U69,593 binding by (-)-1 to be through an increase in the Kd without effect on the Bmax. (-)-1 failed to effect mu or delta binding in rat or guinea pig brain under the same conditions. The enantiomer of (-)-1, (1R,2R)-trans-2-isothiocyanato-N-methyl-N-[2- (1-pyrrolidinyl)cyclohexyl]benzeneacetamide [(+)-1], failed to affect kappa receptors labeled by [3H]-U69,593 under the same conditions as for (-)-1. (1S,2S)-trans-3-Isothiocyanato-N-methyl-N-[2- (1-pyrrolidinyl)cyclohexyl]benzeneacetamide [(-)-2] inhibited to 49.6 +/- 5.1% of the control, in a wash-resistant manner, kappa receptors labeled by [3H]-U69,593. However, (-)-2 was not as selective as (-)-1 since it also reduced [3H]DADLE (delta) binding to 82.4 +/- 8.0% of the control value. (1S,2S)-trans-4-Isothiocyanato-N-methyl-N-[2-(1-pyrrolidinyl)- cyclohexyl]benzeneacetamide [(-)-3] exhibited selective wash-resistant inhibition of delta receptors labeled by [3H]DADLE resulting in a reduction in binding to 42.9 +/- 4.2% of control.(ABSTRACT TRUNCATED AT 400 WORDS)

ChemInform Abstract: Anticonvulsant Activity of Some 4‐Aminophenylacetamides.

Abstract4‐Nitrophenylacetic acid (I) is converted to the amides (III) and reduced to form the title compounds (IV).

Mutagenicity of mono-nitrobenzene derivatives in the Ames test and rec assay

The mutagenicities of 37 mono-nitrobenzene derivatives, i.e. the ortho, meta, and para isomers of nitrotoluene, nitrophenol, nitroaniline, nitroanisole, nitrobenzaldehyde, nitrobenzyl chloride, nitrobenzonitrile, nitroacetophenone, nitrophenetol, nitrobenzoic acid, nitrophenylacetic acid, and nitrocinnamic acid and p-nitrothiophenol, were tested in the Ames test and rec assay. The rec assay gave more positive results than the Ames test. The para-substituted nitrobenzene derivatives were always positive in the rec assay as were all but 2 in the Ames test, while 5 out of 12 ortho and meta derivatives were mutagenic in the Ames test. The results of the present study, combined with those of the previous study, are discussed with special reference to the structure-mutagenicity relationships.

Syntheses of Some New Mannich Bases Using 2, 6-Dimethylmorpholine as Amine Moiety

The use of 2, 6-dimethylmorpholine as an amine moiety in Mannich reaction has been investigated. Nine new Mannich bases have been synthesized using nine different ketones. The salts of β -amino esters have also been synthesized by Mannich reaction using p -nitrophenylacetic acid, formaldehyde solution (37 per cent), and three different amines (2, 6-dimethylmorpholine, piperidine, and 4-methylpiperidine) followed by esterification. The structures of these compounds have been established by infrared spectra, mass spectra, and elemental analyses.

The attempted conversion of nitrobenzyl chlorides to nitrophenylacetic acids

The attempted conversion of nitrobenzyl chlorides to nitrophenylacetic acids

CCCCIII.—Experiments on the synthesis of phenolic aporphines. Part II. The protection of hydroxyls by the carbethoxyl group, and the action of benzyl chloride on nitrophenylacetic acids

CCCCIII.—Experiments on the synthesis of phenolic aporphines. Part II. The protection of hydroxyls by the carbethoxyl group, and the action of benzyl chloride on nitrophenylacetic acids