N-Benzyl phosphoramidate was protected at nitrogen with a TMS, p-toluenesulfonyl, Boc, lithium carboxylate, or diethoxyphosphinyl group and metalated s-BuLi LDA -78 degrees C the benzylic carbon. For latter three protecting groups, intermediate alpha-amino(phenylmethyl)lithiums isomerized to N-protected alpha-aminophosphonates (phosphoramidate-aminophosphonate rearrangement). (R)-N-[1-(2)H(1)]Phenylmethyl in combination Boc (EtO)(2)P(O) used demonstrate that metalation occurs high primary...

Abstract [2‐(Benzyloxy)‐1‐hydroxyethyl]phosphonsäure‐dimethylester [ rac ‐( 7 )] wurde durch Derivatisierung mit dem dimeren Lactol (+)‐ 8 in die chromatographisch trennbaren Diastereomeren 9 und 10 übergeführt. Daraus wurden Abspaltung des chiralen Hilfsstoffs enantiomeren Phosphonate (‐)‐ e.e. ≧ 98% hergestellt. Auf Grund der Röntgenstrukturanalyse Urethans 12 besitzt ( S )‐Konfiguration. Durch Umfunktionalisierung aus (2‐Amino‐1‐hydroxyethyl)phosphonsäuren 1 gewonnen. Das Acanthamoeba...

The enzymes PhnY and PhnZ comprise an oxidative catabolic pathway that enables marine bacteria to use 2-aminoethylphosphonic acid as a source of inorganic phosphate. is notable for catalyzing the cleavage carbon-phosphorus bond using Fe(II) dioxygen, despite belonging large family hydrolytic enzymes, HD-phosphohydrolase superfamily. We have determined high-resolution structures bound its substrate, (R)-2-amino-1-hydroxyethylphosphonate (2.1 Å), buffer additive, l-tartrate (1.7 Å). reveal...

The enzyme family harboring the post-translationally formed 5-methylene-3,5-dihydro-4H-imidazol-4-one (MIO) catalytic residue comprises both aromatic amino acid ammonia-lyases (ALs) and 2,3-aminomutases (AMs). structural origin of different functions role inner loop region in substrate binding are not fully understood. Here, we provide three-dimensional structures for Petroselinum crispum phenylalanine AL (PcPAL) with resolved loops a catalytically competent conformation. Using molecular...

The essential oils of the aerial parts Jasonia candicans and J. montana were analyzed by gas chromatography-mass spectrometry (GC/MS) technique. Of twenty-one components identified in volatile oil candicans, intermediol was main constituent. Fifty-eight characterized montana. Camphor, borneol, bornyl acetate, chrysanthemol, intermediol, 1,8-cineole major constituents this oil. two showed antibacterial activity against Bacillus subtilis. They also a marked antifungal Trichophyton...

ABSTRACT The biodegradation by Rhizobium huakuii PMY1 of up to 10 mM phosphonomycin as a carbon, energy, and phosphorus source with accompanying P i release is described. This represents further mechanism resistance this antibiotic novel, phosphate-deregulated route for organophosphonate metabolism spp.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBiosynthesis of natural products with a phosphorus-carbon bond. 7. Synthesis [1,1-2H2]-, [2,2-2H2]-, (R)- and (S)-[1-2H1](2-hydroxyethyl)phosphonic acid (R,S)-[1-2H1](1,2-dihydroxyethyl)phosphonic incorporation studies into fosfomycin in Streptomyces fradiaeFriedrich Hammerschmidt Hanspeter KaehligCite this: J. Org. Chem. 1991, 56, 7, 2364–2370Publication Date (Print):March 1, 1991Publication History Published online1 May 2002Published inissue 1...

Derivatives of etomidate were evaluated as inhibitors adrenal steroid 11β-hydroxylations. Stereoselective coupling by Mitsunobu produced chirally pure analogues to study the effect configuration, modification ester, and substitution in phenyl ring, with aim probe specific sites for introducing a radionuclide. Iodophenyl metomidate (IMTO) labeled iodine-131 served radioligand structure−affinity relationship studies. We have characterized kinetic parameters 131I-IMTO binding on rat membranes...

Enantiopure stannyl-[D1]methanol was converted to chloro-[D1]methylstannane under complete inversion of configuration using Ph3P/N-chlorosuccinimide in THF. It transmetalated stereospecifically give chloro-[D1]methyllithium (ee up 98%). Its microscopic configurational stability tested by performing tin-lithium exchange the presence benzaldehyde as electrophile various conditions. The macroscopic addressed same but adding it 30 s after addition MeLi used for transmetalation....

Stereochemical investigations have shown that the conversion of 2-hydroxyethylphosphonate to hydroxymethylphosphonate by enzyme HEPD involves removal pro-S hydrogen at C2 and, surprisingly, loss stereochemical information C1. As a result, mechanisms previously proposed for must be re-evaluated.

(Tributylstannyl)methyl 2,2,6,6-tetramethylpiperidine-1-carboxylate was metalated with t-BuLi/TMEDA at -78 degrees C and borylated the mixed borate derived from (R,R)-1,2-dicyclohexylethane-1,2-diol t-butanol to give diastereomeric boronates 31/32 in equal amounts. Boronates 31 32 were reduced LiBEt3D then oxidized basic H2O2 (S)- (R)-tributylstannyl-[1-2H1]methanol of 99% ee, respectively. Treatment their respective phosphates n-BuLi 0 gave microscopically configurationally stable...

The configurational stability of enantiopure chiral (2,4,6-triisopropylbenzoyl)oxy-[D1]methyllithium generated by a tin−lithium exchange was tested on the macroscopic time scale, employing trapping experiments with benzaldehyde. It found to be configurationally stable for minutes at −78 °C and an appropriate substitute carbamoyloxy-substituted analogue in terms cleavage. Its addition several electrophiles studied, leading protocol preparation primary deuterated alcohols, exemplified...

Abstract Enantiomerically pure fluoro‐[D 1 ]methyllithium and iodo‐[D ]methyllithiums of up to 92 % ee were generated by transmetalation the corresponding stannanes with MeLi in THF at various temperatures. The intermediate halo‐[D trapped benzaldehyde or acetophenone already present excess reaction mixture either give halohydrins disintegrate carbene. found be microscopically configurationally stable within tested range −95 0 °C, but chemically only temperatures below °C due a rapidly...

Fom3, a cobalamin-dependent radical S-adenosyl-l-methionine (SAM) methyltransferase, catalyzes C-methylation at the C2 position of cytidylylated 2-hydroxyethylphosphonate (HEP-CMP) to afford 2-hydroxypropylphosphonate (HPP-CMP) in fosfomycin biosynthesis. In this study, Fom3 reaction product HPP-CMP was reanalyzed by chiral ligand exchange chromatography confirm its stereochemistry. The methylation found be (S)-HPP-CMP only, indicating that stereochemistry catalyzed is (S)-selective....

Racemic α-acyloxyalkylphosphonates (±)-4 are prepared and tested for kinetic resolution by lipases AP 6 to a minor extent F-AP 15. The former proves be useful enzyme in terms of broadness application, reaction rate enantiomeric excess. Lipase 15 transformed neither the two substrates checked hydrolysis. Enzymatic hydrolysis α-acyloxyphosphonates containing straight chain alkyl groups with lipase yields (S)-α-hydroxyalkylphosphonates 3 preferentially. Substrates branched hydrolysed lower...

(R, S)-, (R)- and (S)-(2-Hydroxy-[1, 1-2H2]propyl)phosphonic acid were fed to Streptomyces fradiae producing fosfomycin isolated as the corresponding ring-opened aminophosphonic acid. Only (S)(2-hydroxy-[1,1-2H2]propyl)phosphonic was efficiently incorporated into (37% deuterium at C-1 of acid). (R,S)-(2-[18O]Hydroxypropyl)phosphonic gave [1-18O]aminophosphonic None four stereoisomeric (1,2-dihydroxy-[1-2H1]propyl)phosphonic acids labelled fosfomycin. Both (1R,2S)-...

Cation exchange type chiral stationary phases (CSPs) based on 3,5-dichlorobenzoyl amino acid and phosphonic derivatives as selectors (SOs) silica chromatographic support were developed applied to enantiomer separations of bases by nonaqueous capillary electrochromatography (NA-CEC). As a rationale for efficient CSP development we adopted the combined use "reciprocity principle recognition" ion-pair CE screening assay. Thus, (S)-atenolol was employed counter-ion added BGE in series...