Jarosław Lewkowski

The electrochemical oxidation of 5-hydroxymethylfurfural with the nickel oxide/hydroxide electrode

Abstract The electrochemical oxidation of 5-hydroxymethylfurfural with nickel oxide/hydroxide anode gave 2,5-furandicarboxylic acid in 71% yield.

SYNTHESIS AND ITS STEREOCHEMISTRY OF AMINOPHOSPHONIC ACIDS DERIVED FROM 5-HYDROXYMETHYLFURFURAL

Abstract Some dialkyl N-substituted-α-amino-α-furylmethanephosphonates were synthesized via the addition of dialkyl phosphites to corresponding imines in mild conditions in a short time. When an imine is chirally N-substituted the reaction is stereoselective. Stereochemical aspects of the reaction in the light of Cram rules is discussed in this paper.

SYNTHESIS OF 1-AMINOALKANEPHOSPHONIC ACID DERIVATIVES CONTAINING FURAN MOIETY. PART II: FIRST SYNTHESIS OF (2-FURYL)AMINOMETHANE PHOSPHONIC ACID1

Abstract The synthesis of (2-furyl)aminomethanephosphonic acid from furfural via corresponding imine, dibenzyl ester and N-benzylsubstituted acid is presented. The synthesis was performed by the hydrogenolysis of a corresponding N-benzylsubstituted dibenzyl ester.

The first synthesis of ferrocenyl aminophosphonic esters

Abstract The series of aminophosphonates bearing the ferrocenyl moiety was obtained by the addition of dialkyl phosphites to an azomethine bond of Schiff bases. Some successful attempts to perform the asymmetrical synthesis of aminophosphonates were made, but the isolation of diastereomers failed.

The Stereochemical Behavior of Terephthalic Schiff Bases in Addition of Dialkyl or Diaryl Phosphites

Abstract Addition of dialkyl (or diaryl) phosphites to N-alkyl terephthalic Schiff bases led exclusively to a meso-form but addition to N-aryl terephthalic Schiff bases depended on the substituent of the aryl group. Semi-empirical calculations were involved to find the reason of this phenomenon.

The Effect of New Thiophene-Derived Aminophosphonic Derivatives on Growth of Terrestrial Plants: A Seedling Emergence and Growth Test

The aim of this work was to synthesize selected thiophene-derived aminophosphonic systems and evaluate the phytotoxicity of newly obtained products according to the OECD 208 Guideline. Seven new thiophene-derived N-substituted dimethyl aminomethylphosphonic acid esters 2a–h were synthesized by the addition of an appropriate phosphite to azomethine bond of starting Schiff bases 1a–h, and NMR spectroscopic properties of aminophosphonates were investigated. These eight compounds were analyzed in regard to their phytotoxicity towards two plants, radish (Raphanus sativus) and oat (Avena sativa). On the basis of the obtained results, it was found that tested aminophosphonates 2a–h showed an ecotoxicological impact against selected plants, albeit to various degrees.

Evaluation of ecotoxicological impact of new pyrrole-derived aminophosphonates using selected bioassay battery

Six new dimethyl N-arylamino(2-pyrrolyl)methylphosphonates 2a–f were synthesized by the modified aza-Pudovik reaction. Their ecotoxicological impact using battery of bioassay was assessed using Microtox and Ostracodtoxit tests as well as phytotoxicity towards two plants, dicotyledonous radish (Raphanus sativus) and monocotyledonous oat (Avena sativa) following the OECD 208 Guideline. Ecotoxicological properties of compounds 2a–f in aspect of acute and chronic toxicity were evaluated using Heterocypris incongruens and Aliivibrio fisheri tests. The obtained results showed that tested aminophosphonates 2a–f have moderate-to-high phyto- and ecotoxicological impact. They are toxic for both plants but more toxic against dicotyledonous. The investigated compounds showed important ecotoxicity against Heterocypris incongruens crustaceans and Aliivibrio fisheri bacteria. It was found that the substituents of the phenyl ring plays a key role in the degree of toxicity. Results showed that investigated compounds are ecologically toxic and that any of their application should be implemented with care.

Synthesis, Spectral Characterization of Several Novel Pyrene-Derived Aminophosphonates and Their Ecotoxicological Evaluation Using Heterocypris incongruens and Vibrio fisheri Tests

Four diphenyl pyrene-derived aminophosphonates were synthesized. Attempts were made to synthesize diphenyl N-(R)-α-methylbenzylamino(pyren-1-yl)methylphosphonate (3e) in order to obtain the chiral aminophosphonate bearing a pyrene moiety. Because these attempts failed, dimethyl and dibenzyl N-(R)-α-methylbenzyl substituted aminophosphonates 4 and 5 were synthesized and the predominant diastereoisomer of dimethyl aminophosphonate 4 was isolated. The resolution of the diastereomeric mixture of 5 failed. Aminophosphonates 3a–d and the predominant diastereoisomer of 4 were investigated in terms of their ecotoxicity using tests performed on the ostracode Heterocypris incongruens and the fluorescent bacterium Vibrio fisheri. The tests confirmed the moderate-to-high ecotoxicity of aminophosphonates 3a–d and 4, but no evident correlation between the structure and toxicity has been found.

Synthesis, fluorescence properties and the promising cytotoxicity of pyrene–derived aminophosphonates

Summary A large series of variously substituted amino(pyren-1-yl)methylphosphonic acid derivatives was synthesized using a modified aza-Pudovik reaction in 20–97% yields. The fluorescence properties of the obtained compounds were investigated revealing that N-alkylamino(pyren-1-yl)methylphosphonic derivatives are stronger emissive compounds than the corresponding N-aryl derivatives. N-Benzylamino(pyren-1-yl)methylphosphonic acid displayed strong fluorescence (ΦF = 0.68) in phosphate-buffered saline (PBS). The influence of a series of derivatives on two colon cancer cell lines HT29 and HCT116 was also investigated. The most promising results were obtained for N-(4-methoxyphenyl)amino(pyren-1-yl)methylphosphonate, which was found to be cytotoxic for the HCT116 cancer cell line (IC50 = 20.8 μM), simultaneously showing weak toxicity towards normal lymphocytes (IC50 = 230.8 µM).

THE STUDY OF THE REACTION BETWEEN THIOPHOSPHORYL ESTERS AND BORON TRIBROMIDE. THE SYNTHESIS OF OXATHIAPHOSPHABORETANES

Abstract Reactions between three thiophosphoryl esters and boron tribromide are reported. O,O,O-triethyl phosphorothionate (1) and O,O-diethyl methanephosphonothionate (5) gave substituted oxathiaphosphaboretanes 4 and 7 respectively. O-methyl diphenyl-phosphinothionate (9) led to the complex 11 and the corresponding oxathiaphosphaboretane 12. In order to establish the mechanism, reactions were monitored by the multinuclear NMR spectroscopy.