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In a basic medium, 5-Mercapto-1,2,4-triazoles pass into the thiol form, allowing their transformation into sodium salts, which, in reaction with sodium monochloroacetate, lead to sodium 5-thioacetates of 1,2,4-triazoles-3,4-disubstituted. Sulfur derivatives converted to pivalic mixed anhydrides were used as active forms in the acylation of 6-amino penicillanic acid (6-AP) to obtain new semisynthetic penicillins. They contain in the molecule, together with the β-lactam ring, the nucleus 3-[(5-nitroindazol-1′-yl-methyl)]-4-aryl-5-mercapto-1,2,4-triazole, both contributing to an important antibacterial effect. The structure of the new antibiotics was confirmed by the results of elemental and spectral analysis (FT-IR, 1H- and 13C-NMR). The synthetic penicillins were tested for toxicological action and antibacterial activity and the obtained results were close to those for amoxicillin, the reference drug.

Bacterial oral diseases are chronic, and, therefore, require appropriate treatment, which involves various forms of administration and dosing of the drug. However, multimicrobial resistance is an increasing issue, which affects the global health system. In the present study, a commercial amphiphilic copolymer, Pluronic F127, was used for the encapsulation of 1-(5′-nitrobenzimidazole-2′-yl-sulphonyl-acetyl)-4-aryl-thiosemicarbazide, which is an original active pharmaceutical ingredient (API) previously synthesized and characterized by our group, at different copolymer/API weight ratios. The obtained micellar systems, with sizes around 20 nm, were stable during 30 days of storage at 4 °C, without a major increase of the Z-average sizes. As expected, the drug encapsulation and loading efficiencies varied with the copolymer/API ratio, the highest values of 84.8 and 11.1%, respectively being determined for the F127/API = 10/1 ratio. Moreover, in vitro biological tests have demonstrated that the obtained polymeric micelles (PMs) are both hemocompatible and cytocompatible. Furthermore, enhanced inhibition zones of 36 and 20 mm were observed for the sample F127/API = 2/1 against S. aureus and E. coli, respectively. Based on these encouraging results, it can be admitted that these micellar systems can be an efficient alternative for the treatment of bacterial oral diseases, being suitable either by injection or by a topical administration.

In order to obtain new substances with potential biological activity dipeptide derivatives from p-aminobenzoyl-phenylglycine and p-aminobenzoyl-phenylalanine were grafted on 1,2,4-triazolic heterocycle. The new synthesized compounds belong to the group of antimetabolites, group used in medicine for treating malignant tumors. Also, it is possible to study the correlation between chemical structure and biological activity of the new compounds.

Original results are presented in the field of research that addresses the extension of the reaction of residue of acyl-thiosemicarbazide fixation on the structure of 5-nitrobenzimidazole by a sulphonic group. The aim of the study is the increase of new thiosemicarbazide derivatives’ applicative potential in the field of biochemistry, with a wide range of medical applications. The newly obtained compounds were characterized by using elemental analysis and spectral analysis (FT-IR and 1H NMR). A study regarding the optimization of the chemical reactions was made. The performed in vitro biological tests confirmed the tuberculostatic activity of three newly obtained compounds against Mycobacterium tuberculosis.

Dipeptide derivatives from p-aminobenzoyl-phenylglycine and p-aminobenzoyl-phenylalanine were grafted on 1,2,4-triazole heterocycle in order to get new substances with potential biological activity...

International audience; New polymer-bioactive compound systems were obtained by immobilization of triazole derivatives onto grafted copolymers and grafted copolymers carrying betaine units based on gellan and N-vinylimidazole. For preparation of bioactive compound, two new types of heterocyclic thio-derivatives with different substituents were combined in a single molecule to increase the selectivity of the biological action. The 5-aryl-amino-1,3,4 thiadiazole and 5-mercapto-1,2,4-triazole derivatives, each containing 2-mercapto-benzoxazole nucleus, were prepared by an intramolecular cyclization of thiosemicarbazides-1,4 disubstituted in acidic and basic medium. The structures of the new bioactive compounds were confirmed by elemental and spectral analysis (FT-IR and 1H-NMR). The antimicrobial activity of 1,3,4 thiadiazoles and 1,2,4 triazoles was tested on gram-positive and gram-negative bacteria. The triazole compound was chosen to be immobilized onto polymeric particles by adsorption. The Langmuir, Freundlich, and Dubinin–Radushkevich adsorption isotherm were used to describe the adsorption equilibrium. Also, the pseudo-first and pseudo-second models were used to elucidate the adsorption mechanism of triazole onto grafted copolymer based on N-vinylimidazole and gellan (PG copolymer) and grafted copolymers carrying betaine units (PGB1 copolymer). In vitro release studies have shown that the release mechanism of triazole from PG and PGB1 copolymers is characteristic of an anomalous transport mechanism.

New di-(β-chloroethyl)-amides of some acids derived from 2-mercaptobenzoxazole were prepared by reaction of the corresponding pivalic mixed anhydrides with di-(β-chloroethyl)-amine. A study regarding the optimization of the chemical reactions was made for the case of di-(β-chloroethyl)-amines. The quantum chemical analysis by Spartan’14 was made in order to establish the most stable configuration of the ground electronic states for the obtained chemical structures and some physico-chemical parameters of N-mustards reported in this paper. Mercaptobenzoxazoles substituted in the side chain with the cytotoxic group show antitumor activity and they inhibit Ehrlich Ascites in an appreciable proportion compared to the drug I.O.B.-82, as our studies evidenced.

New grafted copolymers possessing structural units of 1-vinyl-3-(1-carboxymethyl) imidazolium betaine were obtained by graft copolymerization of N-vinylimidazole onto gellan gum followed by the polymer-analogous reactions on grafted polymer with the highest grafting percentage using sodium chloroacetate as the betainization agent. The grafted copolymers were prepared using ammonium persulfate/N,N,N&prime, N&prime, tetramethylethylenediamine in a nitrogen atmosphere. The grafting reaction conditions were optimized by changing one of the following reaction parameters: initiator concentration, monomer concentration, polymer concentration, reaction time or temperature, while the other parameters remained constant. The highest grafting yield was obtained under the following reaction conditions: ci = 0.08 mol/L, cm = 0.8 mol/L, cp = 8 g/L, tr = 4 h and T = 50 &deg, C. The kinetics of the graft copolymerization of N-vinylimidazole onto gellan was discussed and a suitable reaction mechanism was proposed. The evidence of the grafting reaction was confirmed through FTIR spectroscopy, X-ray diffraction, 1H-NMR spectroscopy and scanning electron microscopy. The grafted copolymer with betaine structure was obtained by a nucleophilic substitution reaction where the betainization agent was sodium chloroacetate. Preliminary results prove the ability of the grafted copolymers to bind amphoteric drugs (cefotaxime) and, therefore, the possibility of developing the new sustained drug release systems.

Amidic compounds, derivatives of the 5-nitro-benzimidazolyl-2-mercapto-acetic acid were obtained in order to get new cytostatic substances. Two azotyperitic derivatives were obtained by the grafting of the di-(b-chloroethyl)-amine group on molecules of two of the amidic compounds. The NMR and FT-IR spectra confirmed the structure of the new compounds. The mitodepresive action of the new compounds has been tested on root meristems of Lepidiumm sativum L.

Porous microparticles of chitosan- g -poly(glycidyl methacrylate) were obtained by grafting chitosan onto crosslinked networks based on glycidyl methacrylate and ethylene glycol dimethacrylate using suspension polymerization technique. A new cephalosporin from the indazole class prepared by acylation of 7-Aminodesacetoxycephalosporanic acid with mixed anhydride of 5-nitroindazole-1-yl-acetic acid was used as active principle. The cephalosporin-microparticle systems were characterized by FT-IR spectroscopy, SEM and AFM analysis. Batch experiments were carried out to study the influence of initial drug concentration, temperature, contact time, drug:microparticles ratio and pH on the adsorption process of cephalosporin onto porous crosslinked microparticles. Two-parameter and three-parameter isotherm models were used to evaluate the adsorption equilibrium. The values of diffusion coefficients indicate that the cephalosporin adsorption onto microparticles was controlled by both film diffusion and pore diffusion mechanisms. The analysis of the kinetic data of the release process indicate that the release mechanism of cephalosporin from microparticles corresponds to the anomalous transport mechanism.

Two derivatives of glutamine were synthesized and the most convenient physical conditions for obtaining reactions were established in factorial experiments with temperature and time of reactions considered as relevant variables. A quantum-mechanical characterization for the new compounds was performed by using HyperChem 8.0.6 Programs and their physical and chemical properties were theoretically estimated. The toxicity of two new compounds was experimentally determined.

Recently, it has been reported that the compounds bearing a sulfonamide moiety possess many types of biological activities, including antimicrobial activity. The synthesis of new sulfonamides obtained by condensation of 5-nitroindazole with the sulphochlorides of some methyl esters of substituted phenoxyacetic acid, toxicological evaluation of some synthesized 5-nitroindazole sulfonamides and their potential antimicrobial activity were discussed in this paper. The conditions in which the reactions take place with the highest yield were established. The optimization reactions were realized in a 32 factorial experiment. Some physico-chemical properties of the new synthesized compounds were theoretically established by using Spartan'14. The chemical structure of the synthesized compounds was confirmed through elemental and spectral (FT-IR and 1H-NMR) means. Toxicological tests show that sulfonamides derived from 5-nitroindazole are compounds with antimicrobial activity.

A number of new hydrazones with biological activity are synthesized on the basis of 5-nitroindazole. The most efficient conditions of their synthesis with maximum reaction yield are established. The chemical structure of new compounds is found by the elemental analysis, FTIR spectroscopy, and 1H-NMR method. The data of spectral analysis were verified by calculations with the HyperChem software. Toxicological tests indicate that the synthesized hydrazones have the antitumor effect., Синтезовано ряд нових гiдразонiв з бiологiчною активнiстю на основi 5-нiтроiндазола. Встановлено найбiльш ефективнi умови їх синтезу з максимальним виходом реакцiї. Хiмiчна структура нових сполук визначена елементним аналiзом i методами iнфрачервоної спектроскопiї з фур’є-перетворенням i ЯМР. Данi спектрального аналiзу перевiренi розрахунками з програмою HyperChem. Токсикологiчнi тести свiдчать про те, що синтезованi гiдразони володiють антипухлинним ефектом.

New compounds with biological activity based on hydroxy-amino derivatives of benzoxazolyl-2-mercaptoformic acid, benzoxazolyl-2-mercaptoacetic acid, and chloracetyl-2-mercaptobenzoxazole have been synthesized. The chemical bonding of these compounds to poly(maleic anhydride-alt-vinyl acetate), through esterification, leads in obtaining conjugates of polymer biologically active compound type, tests indicating a sustained release of the active chemical, with time (between 5 and 6 h). Reaction products were characterized through elemental and spectral analysis (FTIR and 1H NMR). Toxicology and antimicrobial activity tests recommend compounds with small molecule, as well as their conjugates as therapeutical candidates (antimicrobial inhibitors) for pharmacological application.

cited By 4; International audience; Novel drug-polymer conjugates were prepared by chemical immobilization of hydrazides on poly (N-vinyl pyrrolidone-alt-itaconic anhydride) support. Hydrazides with tuberculostatic activity were synthesized as derivatives of N-(p-nitrobenzoyl)-L-glutamine. Elemental and spectral analysis confirmed the chemical structure of the newly synthesized compounds and the evaluation of biological activity showed an increase of the tuberculostatic effect and a lower toxicity by chemically linking the hydrazides onto co-polymer. © 2013 Copyright Taylor and Francis Group, LLC.

The synthesis of new derivatives of 1,3,4-thiadiazoles and 1,2,4-triazoles was achieved using the 1,4-disubstituted thiosemicarbazides as intermediaries.

International audience; The aim of this research was the synthesis of novel 2,3-disubstituted 1,3 thiazolidines, derived from 5- nitroindazole with antimicrobial activity and their encapsulation into polymer nanocapsules. Starting from previously synthesised hydrazones, there have been obtained novel thiazolidines by reaction with thioglycolic acid. The envisaged chemical structures were confirmed by spectral and elemental analysis. Two of the obtained thiazolidines were encapsulated into cationic Eudragit E100 nanocapsules, obtained by nanoprecipitation. In order to enhance drug release characteristics and particle stability, Eudragit E100 nanocapsules were covered with anionic polysaccharide (sodium alginate), thus forming a complex polyelectrolyte based membrane. The obtained nanocapsules presented a slower and more controlled drug release. The synthesized active principles, in free state and encapsulated into polymer nanocapsules, were tested for their acute toxicity and their influence on the development of model bacterial strains (Staphylococcus mutans, Actinobacillus actinomycetemcomitans, Bacillus subtilis, Bacillus cereus, Salmonella enteritidis, Escherichia coli and Staphylococcus aureus).

Chitosan-based hydrogels are widely used as ophthalmic drug delivery systems due to the polymer advantageous properties. The present work was focused on synthesis and characterization of new chitosan derivatives with polymerisable functions, by reaction with maleic anhydride. The influence of nature and amount of micromolecular reagent, as well as the reaction temperature upon the functionalization degree and solubilization properties of the new derivatives were evaluated. New hydrogels based on chitosan derivatives were prepared by cross-linking reaction with PNIPAM and PHEMA and they were characterized by evaluating their swelling behaviour and their ability to load and release Pilocarpine hydrochloride.

The paper presents the experimental studies regarding synthesis and characterization of hydrogels based on gellan (Gel)/chitosan (CS) and collagen (Col), obtained by crosslinking with glutaraldehyde (GLA). The influence of the polysaccharide content and GLA ratio on the final composition and swelling characteristics was evaluated. Hydrogels swelling analysis, in distilled water and phosphate buffer (PBS, pH 7.2) has shown higher swelling degrees at increased concentration of polysaccharide into hydrogels. In vitro release of pilocarpine has demonstrated the possibility to use gellan-collagen and chitosan-collagen hydrogels as ophthalmic drug delivery matrix.

New polyanionic polymer conjugates with antitumoral activity are synthesized by chemically binding mustard type alkylating derivatives of di-(β-chloroethyl)-amine and tri-(β-chloroethyl)-amine, respectively, onto poly(maleic anhydride-alt-vinyl acetate). The structures of the compounds are verified by FTIR, 1H NMR, and elemental analysis. The antitumoral activity of these polymeric drugs is evaluated in vivo using carcinosarcoma Walker 256 solid tumors in Wister rats. The conjugates exhibit antitumor regression (ATR) values between 25 and 44% depending on comonomers' structure. In addition, an accumulation in the solid tumors (enhanced permeability and retention (EPR) effect) by these compounds is observed. These compounds also cause small organotropic effects, such as increases in the liver, spleen, and kidney weight.

The paper deals with the study of some polymer-biologically active principle systems characterized by the controlled release of the bioactive component by hydrolyze followed by diffusion. The systems were obtained by coupling the 2-mercapto-benzotiazolyl-acetic acid and N-(m-nitrobenzoyl)-L-methionine on poly(vinyl alcohol) by means of esteric bonds in the presence of diciclohexylcarbodiimide as an activator. The influence of some coupling process parameters on the reaction efficiency was studied, such as the drug/support and activator/support ratios. The coupling products with a maximum content of biologically active compound were characterized by spectral measurements, also as regards the capacity of bioactive compound release under the conditions simulating those within the gastro-intestinal tract. The antibacterial activity of the conjugates against Staphylococcus aureus, Eschrichia coli, Sarcina lutea, and Bacillus subtilis was determined.

The paper deals with the hydrogels of interpenetrated networks obtained by reticulation of a mixture of gellan and poly(vinyl alcohol) with epichlorohydrine in basic medium and their characterization with respect to the swelling capacity in water. The influence of some factors on the reticulation density (estimated indirectly from the swelling characteristics) is followed, namely: the macromolecular components ratio in the mixture, the polymer/reticulation agent ratio, duration, and temperature. By the proper choice of these parameter values, the hydrogels of preset swelling characteristics can be obtained. Preliminary tests proved the possibility of using these materials as carriers for drugs in view of their controlled release.

The study discusses achieving a polymer–drug system in which the macromolecular support is an interpenetrated network based on gellan (Gel) and poly(vinyl alcohol) (PVA). The drug (cephotaxime, CEF) has been included through a diffusion process, from an aqueous solution into a high swelling degree hydrogel. The kinetics of drug inclusion and release, from these macromolecular supports with different swelling characteristics in aqueous media has been studied.

The paper presents the synthesis of benzimidazole derivatives starting from asparagic acid. The reaction products were analysed from physical and chemical point of view and their biological activity (acute toxicity, anti-inflammatory activity and gastric tolerance) was evaluated. The product association with acetylsalicylic acid (Aspirin) improves its anti-inflammatory activity (higher with 38%). For acetylsalicylic acid dosing, in mixtures with benzimidazole derivatives, a new HPLC method has been proposed. The method is reproducible, selective and easy to manipulate. The derivatives based on benzimidazole and asparagic acid and their associates with acetylsalicylic acid present good anti-inflammatory properties.

This paper studies the dicyclohexylcarbodiimide activated coupling reaction through ester-type covalent bonds of an oxazolone derived from N-(m-nitrobenzoyl)-L-asparagic acid, ring opened with 2-benzylbenzimidazole, on gellan. Based on a centered, rotatory, composed, second order experimental design, the regression equation describing the dependence of the amount of drug chemically bonded to the support on the reaction parameters is obtained. The efficiency of the coupling reaction over the variation domain established is maximum when the parameters’ highest values are used. The kinetics of the drug’s release from the support are studied under alkaline hydrolysis conditions.

New spirocompounds have been prepared and their temperature dependences of the electrical conductivity and Seebeck are coefficient studied. Measurements were performed using thin-film samples deposited from the solution. All investigated compounds have semiconducting characteristics. The values of some fundamental parameters (thermal activation energy, ratio of carrier mobilities, etc) have been determined. A correlation between semiconducting properties and molecular structure of the compounds is established.

The paper studies the reaction of catalase’s immobilization on a synthetic polymer (copolymer of the acrylic acid with vinyl alcohol), through amidation of enzyme’s terminal amine groups with the lateralcarboxylic group of the macromolecular support, as activated by dicycloxexyl carbodiimide. The support, possessing the properties of a hydrogel, has been synthesized through copolymerization of the acrylic acid with vinyl acetate, followed by hydrolysis of the acetate groups to the hydroxylic groups. The influence of some reaction parameters (such as the activator/support and enzyme/support ratios, duration) on the efficiency of the enzyme’s coupling was studied. The coupling reactions were realized conformely to a centered, rotator, composed, second order experimental program, which permitted the establishment of the conditions necessary for obtaining a coupling product containing the highest amount of immobilized enzyme. Kinetic study of the reaction catalyzed by the coupling products has indirectly evidenced enzyme’s immobilization to the macromolecular support, and also, a sufficiently high catalytic activity of the enzymatic preparation obtained.

The direct pharmacological properties of amino acids and the possibility of using them as carriers for other active pharmacological substances are well known. Methionine, being able to yield the methyl group, is very important in the treatment of hepatic diseases. Paracetamol acute poisoning causes liver injury in both humans and animals. The study is designed to synthesize some new methionine derivatives and toestablish a possible correlation between the new structure and the pharmacological properties. To this end, acute experimental poisoning with Panadol® (paracetamol) was performed while, for the treatment of liver injury caused by this compound, two original synthesis derivatives of methionine, namely N-(m-nitrobenzoyl)- L-methionine and N-(m-aminobenzoyl)-L-methionine, were used. Male Wistar rats were administeredPanadol® (paracetamol) per oral (7500 mg/kg). N-(m-nitrobenzoyl)-L-methionine (m-NBM) 50 mg/kg andN-(m-aminobenzoyl)-L-methionine (m-ABM) 50 mg/kg were given intraperitoneally, 30 minutes after Panadol® administration. Biochemical parameters such as SGOT, SGPT, serum bilirubin and glycemia were estimated to assess the liver function. Panadol® (paracetamol) poisoning produced an increase in serum transaminases, bilirubin and glicemia. These effects were reduced by treatment with m-NBM and especially m-ABM. These biochemical observations were supplemented by histopathological examination of liver sections. The results obtained with m-ABM were comparable with those reported on methionine, which is a recognised antidote in paracetamol poisoning.

Spiro[4,5]deca-2,7-diene-1,6-dione (2a) and spiro[5,5]undeca-2,8-diene-1,7-dione (2b) were prepared by a direct synthesis starting from diethyl malonate. The two-step 1,2-reductions (NaBH4/CeCl3) of the diones gave cis/trans-diols, which could be easily transformed into diacetates. Both diacetates were subjected to Pd(0)-catalyzed allylic alkylations, in which the relative stereochemistry was retained.

International audience; The results reported represent a continuation of the research on the synthesis of new 2-mercaptobenzoxazole derivatives with potential pharmacological activity and corresponding conjugates prepared by chemical immobilization through ester and amidic bonds onto poly(maleic anhydride-alt-vinyl acetate). New sulfonic compounds derived from 2-mercaptobenzoxazole were synthesized in order to obtain substances with a nucleophilic capacity. Their immobilization on copolymer support, based on poly(maleic anhydride-alt-vinyl acetate) through ester or amidic bonds led to polymer—biologically active principle conjugates with controlled release capacity. Release of the compound immobilized by ester bonds was found to take place in the first 5–6 h. The 2-mercaptobenzoxazole derivatives and the conjugates were characterized using elemental and spectral analysis (FT-IR, 1H-NMR). Toxicological and antimicrobial tests were performed, recommending some of these therapeutics as candidates for pharmacological applications.

Various thiadiazoles (IV) and triazoles of type (V) obtained in two steps from (I) either under acidic or basic conditions, respectively.

New potentially biologically active compounds derived from 2-mercapto-benzoxazole were synthesized and coupled on polymeric support of poly (maleic anhydride-alt-vinyl acetate) for the preparation of polymer-drug conjugates with controlled drug release. All compounds were characterized by elemental and spectroscopy (FT-IR, 1H-NMR) analysis. The toxicological tests recommend the products for further laboratory screening.

The synthesis of some new derivatives of p-aminobenzoic acid and the temperature dependence of the electrical conductivity and Seebeck coefficient for these compounds are studied. The measurements have been performed using thin films deposited from solutions. Investigated compounds show semiconducting properties. Some correlations between these properties and the chemical structure are established. The values of some characteristic parameters (activation energy, ratio of carrier mobilities, etc.) of the studied compounds have been determined.

Little references actually exist on neutralization therapy which could constitute the missing ring from an efficient treatment. As structural model capable to interact with organophosphoric substances, at the level of phosphor (P) atom, the common chemical element of the hole class of substances, was proposed those of benzimidazole. Different quantities of benzimidazole were put in contact with a fix quantity of trichlorphon in acid conditions and formation of a new compound was evidentiated by infrared spectrometry. Similar experiments were made utilizing benzimidazole derivatives (2 methyl or 2 benzyl benzimidazole) and different temperatures: 35°C and 40°C. By increasing massic rate: benzimidazole/triclorfon as well an increased reaction temperature, have favourably influenced trichlorphon capture. The obtained results justified an continuation of researches in the direction of new compounds with a structure similar with that of benzimidazole for funding an efficient neutralization therapy for organophosphoric substances.

cited By 6; International audience; The aim of the article was the synthesis of novel L-phenylalanine derivatives with biological activity and their immobilization into polymeric particles. Thus, new formyl, acetyl and p-methoxy derivatives of L-phenylalanine with antitumor activity were synthesized by reaction with p-nitrobenzoyl chloride, followed by the reduction of nitro group and acylation of the new formed amino group. The chemical structures of the obtained aminoacid derivatives were determined by FT-IR, NMR, MS and elemental analyses. The compounds were encapsulated into chitosan- and gelatin-based submicronic capsules, prepared by double crosslinking (ionic and covalent) in a O/W/O double emulsion. The varying parameter polymer/ionic crosslinker molar ratio was seen to influence particle size, morphology, swelling degree, thermal properties, as well as their capacity to incorporate and release the new active principles. The in vivo acute toxicity and antitumoral effect of aminoacid derivatives in free form or encapsulated were evaluated on rats. Drug encapsulation into polymeric systems was proven to enhance antitumoral activity against implanted Guerin's carcinoma. © Springer Science+Business Media, LLC 2012.

The synthesis of some new derivatives of the asparagic acid is described and the temperature dependence of the electrical conductivity and Seebeck coefficient for respective compounds are studied. The measurements have been performed using the thin films deposited from the solution. Investigated compounds have semiconducting properties. Some correlations between these properties and chemical structure of the compounds are established. The values of some characteristic parameters (activation energy, ratio of carrier mobilities etc.) of the studied compound have been determined.

Spiro[4,5]deca-2,7-diene-1,6-dione ( 2a ) and spiro[5,5]undeca-2,8-diene-1,7-dione ( 2b ) were prepared by a direct synthesis starting from diethyl malonate. The two-step 1,2-reductions (NaBH 4 /CeCl 3 ) of the diones gave cis / trans -diols, which could be easily transformed into diacetates. Both diacetates were subjected to Pd(0)-catalyzed allylic alkylations, in which the relative stereochemistry was retained.

cited By 8; International audience; In order to obtain new compounds with antitumoural action the N-(meta-acylaminobenzoyl)-α-acylaminobenzoyl)-α-aminoacids 4-9 were prepared. These compounds were subsequently converted into the corresponding Δ2-oxazolin-5-ones 10-15, which in turn were submitted to a ring opening reaction with di-(β-chloroethyl)amine to afford the peptide supported N-mustards 16-21, which showed low toxicity and cytostatic activity similar to that of sarcolisine against the Ehrlich ascite and Walker 253 carcinosarcoma. © 2007 by MDPI.