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1.
J. Ty Redd Jerald S. Bradshaw Peter Huszthy Reed M. Izatt 《Journal of inclusion phenomena and macrocyclic chemistry》1997,29(3-4):301-308
Pyrimidino-crown ethers were prepared in 30-50% yields by reactingthe ditosylate derivative of the appropriate oligoethylene glycol with4-methoxy-5-methyl-2,6-pyrimidinedimethanol under basic conditions. A newmacrocyclic ligand containing a proton-ionizable pyrimidone subcyclic unitwas prepared in 88% yield by treating the appropriatepyrimidino-crown ether with 5 M NaOH in 50% (v/v) aqueous methanol.Preliminary complexation properties of some of these new compounds werestudied using various NMR spectral techniques. Good enantiomeric recognitionwas exhibited by a chiral pyrimidino-crown ether for the enantiomers of1-(-naphthyl)ethylammonium perchlorate. 相似文献
2.
Reed M. Izatt Gypzy C. Lindh Peter Huszthy Glen A. Clark R. L. Bruening Jerald S. Bradshaw James J. Christensen 《Journal of inclusion phenomena and macrocyclic chemistry》1989,7(5):501-509
The macrocycle-mediated fluxes of alkali, alkaline earth, and several transition metal cations have been determined and compared in a H2O-CH2Cl2-H2O liquid membrane system using four water-insoluble macrocycles containing a dialkylhydrogenphosphate moiety. Transport of alkali metal cations by these ligands was greatest from a source phase pH = 12 or above into an acid receiving phase (pH = 1.5). Very low fluxes were observed for the transport of the alkaline earth cations and all transition metal ions studied except Ag+ and Pb2+ which were transported reasonably well by these new macrocycles.Deceased: September 5, 1987. 相似文献
3.
Tingmin Wang Jerald S. Bradshaw Janet C. Curtis Peter Huszthy Reed M. Izatt 《Journal of inclusion phenomena and macrocyclic chemistry》1993,16(2):113-122
Significant - interaction is found in the complexes of (S, S)-dimethylpyridino-18-crown-6 with (R)- and (S)-[-(1-naphthyl)ethyl]ammonium perchlorate. This finding is supported by the1H NOESY NMR spectral technique, greater chemical shift changes of aromatic protons in both host and guest molecules upon complexation, and by molecular mechanics calculations. Because of the flexibility of the ligand, the tripod hydrogen bonding causes13C relaxation times of all periphery carbons to decrease without significant selectivity. Rotational energy barrier calculations of the methyl groups of the complexed ligand also show that the (S, S)-host-(R)-guest is the more stable complex. 相似文献
4.
J. Ty Redd Jerald S. Bradshaw Peter Huszthy Reed M. Izatt 《Journal of heterocyclic chemistry》1994,31(4):1047-1052
Eight new macrocyclic ligands containing the pyrimidine subcyclic unit ( 3-10 , Figure 1) have been prepared. Two of these new crown ethers are chiral. Pyrimidino-crowns 3-8 were prepared by treating the di-tosylate derivative of the appropriate oligoethylene glycol with 4-methoxy-5-raethyl-2,6-pyrimidinedimeth-anol in basic conditions. The yields were in the 30-50% range giving the crowns as viscous oils. Chiral dimethyl-substituted pyrimidino-crown 9 was prepared from 4-methoxy-5-methyl-2,6-pyrimidinedimethyl di-tosylate and chiral dimethyl-substituted tetraethylene glycol. Treatment of dimethyl 4-methoxy-5-methyl-2,6-pyrimidinedicarboxylate with the diamine derivative of chiral dibenzyl-substituted tetraethylene glycol gave the chiral dibenzyl-substituted pyrimidino-crown diamide 10. Starting 4-methoxy-5-methyl-2,6-pyrimidinedi-methanol was prepared by a six step process from acetamidine hydrochloride and diethyl oxalpropionate. 相似文献
5.
Reed M. Izatt Gypzy C. Lindh Ronald L. Bruening Peter Huszthy John D. Lamb Jerald S. Bradshaw James J. Christensen 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(6):739-745
The macrocycle-mediated fluxes of several alkali metal cations have been determined in a H2O-CH2Cl2-H2O liquid membrane system. Water-insoluble proton-ionizable macrocycles of the pyridono type were used. The proton-ionizable feature allows the coupling of cation transport to reverse H+ transport. This feature offers promise for the effective separation and/or concentration of alkali metal ions with the metal transport being driven by a pH gradient. A counter anion in the source phase is not co-transported. The desired separation of a particular metal ion involves its selective complexation with the macrocycle, subsequent extraction from the aqueous phase to the organic phase, and exchange for H+ at the organic phase-receiving phase interface. Factors affecting transport which were studied include ring size, source phase pH, and receiving phase pH. Lithium was transported at a rate higher than that of the other alkali metals in both single and competitive systems using a 15-crown-5 pyridono carrier. 相似文献
6.
Gyula Simig Gábor Doleschall Gyula Hornyák József Fetter Károly Lempert József Nyitrai Péter Huszthy Tibor Gizur Mária Kajtár-Peredy 《Tetrahedron》1985,41(2):479-484
Acylation of the N-substituted diethyl aminomalonates 3a–3d with diketene furnished the ring tautomers 6a–6d of the expected acetoacetyl derivatives 5. By treatment with iodine and sodium ethoxide compounds 6a–6d are smoothly converted into the β-lactam derivatives 2a–2d. Deethoxycarbonylation of the ethylene ketals 7a–7d of the latter furnishes mixtures of the corresponding diastereomeric monoesters 8 and10. The ethoxycarbonyl groups of the trans esters 8 are more reactive than those of the cis isomers 10. This permits, under appropriate conditions, selective alkaline hydrolysis and NaBH4 reduction of the trans esters 8 in the presence of the cis esters 10. Reduction of the cis ester 10c under more forceful conditions furnishes the trans hydroxymethyl derivative 11c. 相似文献
7.
Attila Kormos Ildikó Móczár Dávid Pál Péter Baranyai József Kupai Klára Tóth Péter Huszthy 《Tetrahedron: Asymmetry》2013,24(1):62-65
A novel optically active 5,5-dioxophenothiazine-1,9 bis(thiourea) containing glucopyranosyl groups was synthesized and its enantiomeric recognition properties were examined towards the enantiomers of tetrabutylammonium salts of chiral α-hydroxy and N-protected α-amino acids using UV–vis spectroscopy. 相似文献
8.
9.
Takacs Kata Tatraaljai Dora Pregi Emese Huszthy Peter Pukanszky Bela 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12513-12522
Journal of Thermal Analysis and Calorimetry - A new phosphine-type potential secondary stabilizer was synthesized successfully with large natural raw material content. The stabilizer is a waxy... 相似文献
10.
Starting from acridono-18-crown-6 ligand 1 (Fig. 1) seven new proton-ionizable chromogenic and fluorogenic ionophores 2-8 (Fig. 1) containing NO2 group(s) and/or Br or Cl atom(s) in the aromatic rings were prepared by electrophilic substitution. The precursor macrocycle 1 was obtained by a modification of the reported procedure which made chromatography unnecessary in purification and gave higher yield. X-ray crystallographic studies of the complexes of acridono-18-crown-6 type ligands 1, 2, 3, 6 and 8 show that the proton-ionizable units are in the acridone tautomeric form and that the ligands invariably bind a water molecule in their cavities by multipodal hydrogen bonding. In two cases (6 and 8) an additional DMF solvent molecule is also bound at the crown perimeter in the solid state. 相似文献