Jerzy Łuczak

Enzymatic reactions in ionic liquids: lipase-catalysed kinetic resolution of racemic, P-chiral hydroxymethanephosphinates and hydroxymethylphosphine oxides

Abstract Lipase-mediated acetylation of racemic P -chiral hydroxymethanephosphinates and hydroxymethylphosphine oxides was performed in ionic liquids under kinetic resolution conditions. Lipase AK (Amano) and lipase from Pseudomonas fluorescens (Fluka) were up to six times more enantioselective in BMIM·PF 6 solutions than in common organic solvents. On the contrary, the analogous reactions performed in BMIM·BF 4 were practically non-stereoselective.

Novel approach for the simultaneous analysis of glyphosate and its metabolites

A novel approach for the simultaneous analysis of glyphosate (PMG), and aminomethylphosphonic (AMPA, GlyP), N-methylaminomethylphosphonic (MAMPA. SarP) and methylphosphonic (MPA) acids is presented. This includes a preliminary 31P NMR analysis of mixtures of PMG, MPA, AMPA and MAMPA, their further derivatization to volatile phosphonates by means of the trifluoroacetic acid-trifluoroacetic anhydride-trimethyl orthoacetate reagent and subsequent MS [chemical ionization (CI) MS, GC-CI-MS, GC-electron impact ionization MS] and/or GC-flame ionization detection (FID) analysis of the products of derivatization. The detection limits of PMG, AMPA, MAMPA and MPA by means of GC-CI-MS and GC-FID were determined. The calibration graphs (GC-FID) for these derivatives were in the range 0.1 to 100 nmol linear and sufficiently reproducible for quantitative determinations. The applicability of the method was demonstrated during the analysis of water samples fortified with PMG, AMPA and MAMPA, characterized by recoveries of >95%.

Simultaneous analysis of biologically active aminoalkanephosphonic acids

A new approach for simultaneous analysis of biologically active aminoalkanephosphonic acids, namely glyphosate, phosphonoglycine, phosphonosarcosine, phosphonoalanine, phosphono-beta-alanine, phosphonohomoalanine, phosphono-gamma-homoalanine and glufosinate, is presented. This includes a preliminary 31p NMR analysis of these amino acids, their further derivatization to volatile phosphonates (phosphinates) by means of trifluoroacetic acid-trifluoroacetic anhydride-trimethyl orthoacetate reagent and subsequent analysis of derivatization products using MS and/or GC-MS (chemical ionization and/or electron impact ionization).

Stereochemistry of organophosphorus cyclic compounds—I : Stereospecific synthesis of cis- and trans-2-hydroxy-2-thio(seleno)-4-methyl-1.3.2-Dioxaphosphorinans☆

Abstract Geometrical isomers of 2-hydroxy-2-thio-4-methyl-1,3,2-dioxaphosphorinan (I) and 2- hydroxy-2-seleno-4-methyl-1,3,2-dioxaphosphorinan (V) have been prepared stereospecifically by : (a) demethylation of cis - and trans -2-methoxy-2-thio-4-methyl-1,3,2-dioxaphosphorinan (IV) and 2-methoxy- 2-seleno-4-methyl-1,3,2-dioxaphosphorinan (VI) with trimethylamine, and (b) addition of sulphur and selenium to geometrical isomers of 2-hydrogen-2-oxo-4-methyl-1,3,2-dioxaphosphorinan (VIII). It has been demonstrated that addition of sulphur and selenium to the P(O)H grouping proceeds with retention of configuration at the P atom.

The first enantiomerically pure, C2-symmetric spiroselenurane: 3,3,3′,3′-tetramethyl-1,1′-spirobi[3H,2,1]-benzoxaselenole

Abstract The enantiomers of a C2-symmetric spirobisalkoxyselenurane, 3,3,3′,3′-tetramethyl-1,1′-spirobi[3H,2,1]-benzoxaselenole, have been isolated for the first time via chromatographic resolution of the racemate using a chiral HPLC column. The isomers were further characterized by 1H NMR and CD spectroscopic measurements.

New enantiomeric fluorine-containing derivatives of sulforaphane: Synthesis, absolute configurations and biological activity

Three pairs of enantiomers of the unknown sulforaphane analogs bearing organofluorine substituents bonded to the sulfinyl sulfur atom and having different number of methylene groups in the central carbon chain were synthesized and fully characterized, including determination of their absolute configurations. All the new compounds were tested in vitro for their cytotoxicity against melanoma cells to show increased activity in comparison with the natural sulforaphane. The influence of the particular structural changes in the molecule on the cytotoxicity is discussed.

1-( N -Trifluoroacetylamino)alkylphosphonic acids: synthesis and properties

Summary.The 1-(N-trifluoroacetylamino)alkylphosphonic acids (TFA-AAP) – sub-products in the synthesis of O,O-dialkyl 1-(N-trifluoroacetylamino)alkylphosphonates and O,O-diethyl 1-aminoalkylphosphonates, were synthesized in two-stage transformations of 1-aminoalkylphosphonic acids including: trifluoroacetylation of 1-aminoalkylphosphonic acids (AAP) using a trifluoroacetic anhydride/trifluoroacetic acid reagent (AAP + TFAA/TFA→2) and subsequent hydrolysis of the intermediary compounds 2 into desired TFA-AAP (2→TFA-AAP). These intermediates 2 presented mixtures of the type of mixed anhydrides of TFAA and 1-(N-trifluoroacetylamino)alkylphosphonic, pyrophosphonic and polyphosphonic acids, which underwent rapid and quantitative conversion to corresponding TFA-AAP during treatment with an excess of water. The title acids were isolated by direct evaporation of the corresponding post-reaction mixtures, and their physicochemical proprieties, including deacylation abilities, were determined. TFA-AAP compounds can be re-converted into the starting amino acids AAP under respectively mild conditions (AAP→TFA-AAP→AAP).

Synthesis of Enantiomerically Enriched Mono and Bis 2,2′-Bipyridine Alkyl Sulfoxides and Their First Application as Chiral Auxiliaries 1

The direct asymmetric oxidation of 6,6′-bis(alkylsulfanyl)-2,2′-bipyridines 2a–e to non-racemic mono sulfoxides 3a–e and bis-sulfoxides 4a,c–e using either Davis oxaziridine or a modified Sharples reagent is reported. The use of isolated mono- and bis-sulfoxides as chiral auxiliaries was tested in either the asymmetric addition of the diethylzinc or allyl(trichloro)silane to benzaldehyde.

Organofluorine Isoselenocyanate Analogues of Sulforaphane: Synthesis and Anticancer Activity

A series of previously unknown sulforaphane analogues with organofluorine substituents bonded to the sulfinyl sulfur atom, an isoselenocyanate moiety in place of the isothiocyanate group, the central sulfur atom in various oxidation states, and different numbers of methylene groups in the central alkyl chain were synthesized and fully characterized. All new compounds were tested for their biological properties in vitro and demonstrated much higher anticancer activity against two breast cancer cell lines than that shown by native sulforaphane; at the same time, the compounds were less toxic for normal cells. The influence of the particular structural changes in the molecules on the cytotoxicity is discussed.

The reaction of 1,2-dithiole-3-thiones with trivalent phosphorus compounds: Stereochemical and spectroscopic studies

In order to determine the scope and limitation of this potentially new thionation procedure we carried out model stereochemical and spectroscopic studies using optically active methylphenyl-n-propylphosphine 5 and secondary t-butylphenylphosphine oxide 6 and a few achiral tricoordinated organophosporus compounds. We found that the reaction of the thione 1 with trialkyl phosphites is rapid and very clean giving the corresponding thionophosphate in almost quantitative yield (31P-NMR assay). On the other hand triphenyl phosphite gave a complex mixture of phosphorus-containing products. Thionation of the dextrarotatory phosphine 5 using the thione 1 gave the corresponding, dextrarotatory phosphine sulfide with stereoselectivity close to 70%; traces of the corresponding oxide were detected