Malonic Acid Esters Research Articles

Synthesis of malonic acid esters

Synthesis of malonic acid esters

Synthesis of diethyl 6-amino-1,4-diaryl-2-oxo1,2,3,4-tetrahydropyridin-3,5-dicarboxylates based on the reaction of arylmethylidenecyanoacetic esters with <i>N</i>-arylamido esters of malonic acid

The reaction of arylmethylidenecyanoacetic esters with N -arylamides of malonic acid led to the formation of previously unknown diethyl 6-amino-1,4-diaryl-2-oxo-1,2,3,4-tetrahydropyridine-3,5-dicarboxylates in 15-83% yields. Antibacterial activity of some obtained compounds was studied.

Reaction of 2-R-naphtho[2,3-d][1,3,2]dioxaphosphinin-4-ones with arylidene derivatives of malonic acid esters: synthesis, molecular and crystal structures of 5-oxo-2-R-naphtho[2,3-f][1,2]oxaphosphepine 2-oxides

Reaction of 2-R-naphtho[2,3-d][1,3,2]dioxaphosphinin-4-ones with arylidene derivatives of malonic acid esters: synthesis, molecular and crystal structures of 5-oxo-2-R-naphtho[2,3-f][1,2]oxaphosphepine 2-oxides

Photoinduced Atom Transfer Radical Addition/Cyclization Reaction between Alkynes or Alkenes with Unsaturated α-Halogenated Carbonyls.

We have developed a photochemical ATRA/ATRC reaction that is mediated by halogen bonding interactions. This reaction is caused by the reaction of malonic acid ester derivatives containing bromine or iodine with unsaturated compounds such as alkenes and alkynes in the presence of diisopropylethylamine under visible light irradiation. As a result of various control experiments, it was found that the formation of complexes between amines and halogens by halogen-bonding interaction occurs in the reaction system, followed by the cleavage of the carbon–halogen bonds by visible light, resulting in the formation of carbon radicals. In this reaction, a variety of substrates can be used, and the products, cyclopentenes and cyclopentanes, were obtained by intermolecular addition and intramolecular cyclization.

Anthocyanins from a single botanical source can be used as a replacement for hemalum and eosin

ABSTRACT For various reasons, histologists in several parts of the world have tried to replace hematoxylin and eosin with locally available plant dyes of the anthocyanin family. Blue or violet nuclear stains have been created by combining an anthocyanin with iron or aluminum ions at low pH. Obtaining a pink or red cytoplasmic counterstain, however, has not been achieved previously, even with a red solution of anthocyanin, because the chemistry of the colorant does not allow bonding to cytoplasmic materials and collagen. We used two extracts from the petals of common mallow, Malva sylvestris, to create both a blue nuclear stain and a red counterstain. The two extracts contained two chemically distinct types of anthocyanins. The first extract contains vic-hydroxyls capable of complexing aluminum ions; its flavylium core is cationic. The second type lacks vic-hydroxyls on its core structure, but includes pendant glucosides that contain a malonic acid ester with a free carboxyl substituent. The precise identity of the first anthocyanin currently is unknown, but likely is one or more of the common anthocyanins such as cyanidin, delphinidin or petunidin, which complex readily with aluminum. The second anthocyanin is malonated malvidin, which does not complex with aluminum, but is anionic at the pH used here. The overall visual effect of applying the two anthocyanin extracts is remarkably similar to that of hemalum plus eosin.

Enantioselective synthesis of pyrro[3,4-c]quinoline pseudo-natural products

Pseudo natural products (PNPs) are natural product-inspired compounds obtained by unprecedented combination of natural product (NP) fragments in complexity-generating transformations. The pyrrolidine- and tetrahydroquinoline fragments individually occur in numerous NPs with diverse bioactivity, yet not in combination. Herein we report the enantioselectively catalyzed asymmetric synthesis of pyrro[3,4-c]quinoline pseudo-natural products in which these two fragments are combined. The synthesis includes a highly enantioselective 1,3-dipolar cycloaddition between amino acid-derived azomethine ylides and α,β-unsaturated malonic acid esters to yield pyrrolidines followed by a sequence of protection-, reduction- and lactamization steps.

Hybrid molecules based on fullerene C60 and 5Z,9Z-dienoic acids: Synthesis and cytotoxic activity

The present research project details synthesis of new hybrid methanofullerenes based on acetylene and triazole esters of malonic acid containing 5Z,9Z-dienoic acids and fullerene C60 under Bingel-Hirsch conditions, including study of the cytotoxic activity with respect to Jurkat, K562, U937 and HL60 tumor cell lines. Hybrid methanofullerenes containing acetylenic fragments, unlike triazole substituents, were found to exhibit higher cytotoxicity, but are characterized by lower selectivity of action in relation to healthy cells.

Synthesis and Characterization of New Azido Esters Derived from Malonic Acid

AbstractThree new α,α‐diazidated azido esters derived from malonic acid were synthesized and characterized with a method of diazidation under mild reaction conditions. They are energy‐rich, small, liquid molecules which contain up to six azido moieties. The three synthesized compounds were compared to already known azidated malonic acid esters regarding their density, thermal stability, calculated heat of formation and energetic properties. Further they were tested and classified for their sensitivities according to UN guidelines.

Synthesis and Properties of Energy-Rich Methanofullerenes Containing Norbornadiene and Quadricyclane Moieties.

The energy-rich methanofullerenes were synthesized for the first time by the reaction of fullerene C60 with mono- and bisquadricyclane esters of malonic acid. The C-C bond cleavage in the quadricyclane moieties of new hybrid molecules takes place in the presence of catalytic amounts of Cu, Pd, and Pt salts or complexes or SiO2 and is accompanied by heat evolution.

An enantiodivergent synthesis of Cα-methyl nipecotic acid analogues from δ-lactam derivatives obtained through a highly stereoselective cyclization strategy

A stereoselective and enantiodivergent strategy for the construction of δ-lactams is described. The strategy utilizes chiral malonic esters prepared from enantiomerically enriched mono esters of disubstituted malonic acid. A cyclization occurs with the selective displacement of a substituted benzyl alcohol as the leaving group. The resulting δ-lactams are then converted into nipecotic acid analogues using straightforward transformations. The resulting nipecotic acid analogues proved capable organocatalysts in Mannich reactions.

A Facile and Convenient Synthesis of (±)-Biotin via MgCl2/Et3N-Mediated C–C Coupling and Mitsunobu Reaction

A synthesis of (±)-biotin is described starting from simple starting materials viz. cyclohexanone and amino malonic acid ester. The key steps involved are MgCl₂/Et₃N coupling of amino malonic acid ester derivative and acid chloride, Mitsunobu reaction, ozonolysis, Staudinger reduction, novel urea formation, and subsequent dibenzylation. This approach is economical and involves high-yielding steps and simple reaction conditions.

Chemical profile analysis and comparison of two versions of the classic TCM formula Danggui Buxue Tang by HPLC-DAD-ESI-IT-TOF-MSn.

Danggui Buxue Tang (DBT) is a Traditional Chinese Medicine (TCM) formula primarily used to treat symptoms associated with menopause in women. Usually, DBT is composed of one portion of Radix Angelicae Sinensis (RAS) and five portions of Radix Astragali (RA). Clinically, Radix Hedysari (RH) is sometimes used by TCM physicians to replace RA in DBT. In order to verity whether the chemical constituents of the DBT1 (RA:RAS = 5:1, w/w) and DBT2 (RH:RAS = 5:1, w/w) share similarities the chemical profiles of the two DBTs crude extracts and urine samples were analyzed and compared with the aid of HPLC-DAD-ESI-IT-TOF-MSn, which determines the total ion chromatogram (TIC) and multi-stage mass spectra (MSn). Then, the DBT1 and DBT2 were identified and compared on the basis of the TIC and the MSn. In the first experiment (with crude extracts), 69 compounds (C1–C69) were identified from the DBT1; 46 compounds (c1–c46) were identified from the DBT2. In the second experiment(with urine samples), 44 compounds (M1–M44) were identified from the urine samples of rats that had been administered DBT1, and 34 compounds (m1–m34) were identified from the urine samples of rats that had been administered DBT2. Identification and comparison of the chemical compositions were carried out between the DBT1 and DBT2 of the crude extracts and urine samples respectively. Our results showed that the two crude extracts of the DBTs have quite different chemical profiles. The reasons for their differences were that the special astragalosides in DBT1 and the isoflavonoid glycosides formed the malonic acid esters undergo single esterification and acetyl esters undergo acetylation in DBT1. In contrast, the urine from DBT1-treated rats strongly resembled that of DBT2-treated rats. These metabolites originate mainly from formononetin, calycosin and their related glycosides, and they were formed mainly by the metabolic process of reduction, deglycosylation, demethylation, hydrogenation and sulfation. The HPLC-DAD-ESI-IT-TOF-MSn method was successfully applied for the rapid chemical profiles evaluation of two DBTs and their related urine samples.

Novel Approach: Tungsten Oxide Nanoparticle as a Catalyst for Malonic Acid Ester Synthesis via Ozonolysis

Malonic acid ester was synthesized via the one‐step ozonolysis of palm olein. Malonic acid ester was spectroscopically characterized using gas chromatography mass spectroscopy (GC‐MS). Tungsten oxide nanoparticles were used as the catalyst, which was characterized via X‐ray powder diffraction (XRD) and field emission scanning electron microscopy (FE‐SEM). Tungsten oxide provided several advantages as a catalyst for the esterification malonic acid such as simple operation for a precise ozonation method, an excellent yield of approximately 10%, short reaction times of 2 h, and reusability due to its recyclability.

Synthesis and structures of the CH acid salts obtained in the reactions of malonic acid esters and malononitriles with 2,4,6-trinitrohalobenzenes in the presence of triethylamine

Reactions of dimethyl malonate, diphenyl malonate, methyl cyanoacetate, and malononitrile with 1-chloro-2,4,6-trinitrobenzene or 1-fluoro-2,4,6-trinitrobenzene in the presence of triethylamine in organic solvents gave stable brightly colored crystalline triethylammonium salts of the corresponding 2,4,6-trinitrophenylmalonic acid derivatives.

Synthesis and antioxidant activity of long chain alkyl hydroxycinnamates

Long chain alkyl hydroxycinnamates ( 8– 21) were synthesized from the corresponding half esters of malonic acid ( 5– 7) and benzaldehyde derivatives by Knoevenagel condensation. The total antioxidant capacity of these hydroxycinnamyl esters was evaluated using DPPH and ABTS assays. The observed antioxidant activity was highest for esters of caffeic acid followed by sinapic esters and ferulic esters. The parameters for drug-likeness of these hydroxycinnamyl esters were also evaluated according to the Lipinski’s ‘rule-of-five’. All the ester derivatives were found to violate one of the Lipinski’s parameters (cLogP >5), even though they have been found to be soluble in protic solvents. The predictive topological polar surface area (TPSA) data allow concluding that they could have a good capacity for penetrating cell membranes. Therefore, one can propose these novel lipophilic compounds as potential antioxidants for tackling oxidative processes.

Oligomerization in the reaction of acetylacetone with organic diisocyanates

Diisocyanates are organic monomers [1] widely used in the polymer chemistry [2–4]. They are highly reactive compounds toward various nucleophiles such as alcohols, phenols, and primary amines [5]. The corresponding reactions underlie large-scale processes for manufacture of polyurethanes and polyureas. CH Acids are less reactive toward isocyanates. However, such CH acids as malonic acid esters, ethyl acetoacetate, nitroalkanes, and acetylacetone are known [2, 3] to react with diisocyanates at the activated C–H bonds to give substituted amides.

One-pot carbon–carbon bond formation at the β-position of cyclic ketones: oxidative Michael addition with alkyl malonates

A carbon–carbon bond was formed at the β-position of cyclic ketones in a one-pot manner by oxidation with N- tert-butylbenzenesulfinimidoyl chloride, followed by the reaction of malonic acid esters or potassium cyanide.

Stereoselective synthesis of new (+)-1-{(1R,3R,6S)-4,7,7-trimethylbicyclo[4.1.0]hept-4-en-3-yl}ethan-1-one derivatives

A procedure was developed for the stereoselective synthesis of aminated derivatives of (+)-1-{(1R,3R,6S)-4,7,7-trimethylbicyclo[4.1.0]hept-4-en-3-yl}ethan-1-one. The configuration of the side-chain chiral center in (+)-1-{(1R,3R,6S)-4,7,7-trimethylbicyclo[4.1.0]hept-4-en-3-yl}ethan-1-ol was determined by X-ray analysis. Diketene and Meldrum’s acid were proposed as initial compounds for the synthesis of, respectively, 3-oxobutanoic and malonic acid esters having a 1-ethyl-4,7,7-trimethylbicyclo[4.1.0]hept-4-ene fragment.

Synthesis of titanium complexes bearing two mono anionic malonic acid ester based ligands and their use as catalyst precursors in ethene polymerization

In this work titanium dichloro complexes bearing diethylmalonate, diethylphenylmalonate and diphenylmalonate ligands have been synthesized. The complexes were activated by methylaluminoxane (MAO) and exhibited moderate activity [10–50 kg PE/(mol Ti h bar)] in ethene polymerization. The catalysts produced ultra high molar mass polyethene (PE) (up to 3000 kg/mol) with polydispersity values range between 2 and 4.

Solid Phase Synthesis of 2‐Substituted1, 3‐Oxazin‐6‐ones Using Resin‐bound Cyclic Malonic Acid Ester

AbstractA facile solid phase. synthesis of 2‐substituted1,3‐oxazin‐6‐ones using polymer‐supported Meldrum's acid has been reported. Reaction of the resin‐bound cyclic malonic acid ester with triethyl orthoformate and subsequent double substitution with amide, afforded the corresponding polymer‐supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to1, 3‐oxazin‐6‐ones in good yields and with high purity.