A homochiral MOF, PCN-261-NHPro, was prepared via solvothermal synthesis of Fe2CoO(CH3COO)6 with H3tcpb-NHPro. The aldol addition was selected as a model reaction for the estimation of the catalytic performance of the PCN-261-NHPro, which showed reversed diastereomeric selectivity in contrast to...
The N-terminal protected amino acid (Boc-l-proline) is a chiral ligand for the enantioselective phenylacetylene addition to aromatic aldehydes, thus expanding the utility of the simplest enzyme, proline, in asymmetric catalysis. Good yields and enantioselectivities (up to 77% ee) were achieved.
The multi-step preparation of N-Boc-3,4-dehydro-l-proline methyl ester using a modular flow reactor is reported. The use of immobilised reagents and scavengers in pre-packed glass tubes allows us to obtain the pure product in 87% overall yield, 97% purity, and >98% enantiomeric excess without an...
N-Cbz-4,5-dehydro-l-prolineamide or N-Boc-4,5-dehydro-l-prolineamide are alternative key intermediates for the synthesis of saxagliptin, a dipeptidyl peptidase IV (DPP4) inhibitor recently approved for treatment of type 2 diabetes mellitus. An efficient biocatalytic method was developed for conv...
A novel CuI/l-proline catalyzed coupling reaction of 1-Boc-3-iodoazetidine with various arylboronic acids which produced aryloxyazetidine derivatives in moderate to good yields was investigated.
The triphenyltin(IV) compound with N-tert-butoxycarbonyl-l-ornithine (Boc-Orn-OH), [Ph3Sn(Boc-Orn-O)], was synthesized and characterized by elemental analysis, FT-IR, solution 1H, 13C and 119Sn NMR and ESI mass spectrometry. The organotin(IV) compound inhibited at very low micromolar concentrati...
4-Nitrophenyl-β-xylobioside was synthesized by an improved short chemical-enzymatic method, based on the use of xylobiose as a starting material. Xylobiose was prepared following extensive enzymatic digestion of birchwood xylan with xylanase T-6. The resulting digest, containing mainly xylobios...
A short entry to 3a-(o-nitrophenyl)octahydroindol-4-ones employing ozonolysis and double reductive amination of 2-allyl-2-(o-nitrophenyl)-1,3-cyclohexanedione (9) is described. The symmetric dione 9 is synthesized in a 50% overall yield from 1,3-cyclohexanedione by means of o-nitroarylation foll...
The syntheses of 4-nitrophenyl β-glycosides of the 3-thio and 4-thio analogues of the two principal 2-acetamido-2-deoxy-hexoses found in living systems, GlcNAc and GalNAc, are described. While synthesis of the 4-thio analogues could be achieved via nucleophilic displacements of sulfonate deriva...
2,2-Di(4-nitrophenyl)hexafluoropropane (1) and 2,2-di(4-nitrophenyl)propane (2) were synthesized and their crystal structures were determined. The crystals of both diarylpropanes have helical conformations with unsymmetrical ring-twist angles, φA=46.7, φB=33.5° for 1, and φA=64.9, φB=31.8°...
N-(2,2-Dimethyl-2-(2-nitrophenyl)acetyl)-4-aminocyclophosphamide isomers (DMNA-NH-CPA, 4) were synthesized stereospecifically from Boc-l-Hse(OBn)-OH and the degradation of the corresponding reduced amine 5a was investigated by UV/vis spectroscopy and LC/MS. The rate of cyclization of 5a was foun...
2- and 4-Nitrophenyl β-d-xylopyranosides (4 and 5) were transformed, via dibutyltin oxide-mediated acylation, into the corresponding 2,3-di-O-benzoyl derivatives 11 and 15. Xylobiose and xylotriose were easily isolated by charcoal column chromatography from a commercially available material and...
Two chiral organic nonlinear optical materials, (3S,4S)-(−)-6-cyano-2,2-dimethyl-3,4-epoxychroman (1) and (3R,4R)-(+)-6-nitro-2,2-dimethyl-3,4-epoxychroman (2), have been grown into single crystals of cm3-size. Although both compounds crystallise in the orthorhombic P212121 space group, they are...
The asymmetric transfer hydrogenation of a series of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones and 2,2-dimethyl-6-(2-oxoaryl)-1,3-dioxin-4-ones was achieved in high enantiomeric excess using a Ru(II) catalyst. The aryl substrates were most compatible with the methodology and this process fac...
A series of new 2,4,6-trisubstituted pyrimidines and their N-alkyl bromide derivatives were prepared based upon methoxy substituted azachalcones as the starting materials. All newly synthesized compounds were screened for their anti-proliferative, cytotoxic, antibacterial activities and DNA/prot...
A series of novel thiazolidin-4-ones bearing a hydrophobic substituent at 5-position on the 4,6-dimethyl-pyrimidine ring at N-3 (5c–i and 6c–i) were designed on the prediction of QSAR studies, synthesized in good yields of 60.1–85.3% by microwave-assisted one-pot protocol with the combination...
The interaction of organic acceptors such as tetrafluoro-1,4-benzoquinone (p-TFQ), tetrachloro-1,4-benzoquinone (p-TCQ), tetrachloro-1,2-benzoquinone (o-TCQ), tetrabromo-1,4-benzoquinone (p-TBQ), tetrabromo-1,2-benzoquinone (o-TBQ) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) with (4-dime...
Reactions of secondary phosphines HPR1R2 [R1 = R2 = p-MeOC6H4 (b), p-CF3C6H4 (c), mesityl (Mes, d) or 1-adamantyl (Ad, e); R1 = t-Bu, R2 = Ph (f)] with cyclopalladated complexes (CPCs) derived from N,N-dimethylbenzylamine (1), l-fenchone methyloxime (3), (S)-N,N-dimethylbenzylamine (9), and (S)-...
Ferrocene-based phosphine oxides with various substituents at phosphorous atoms were synthesized by Cu-catalyzed reductive coupling of ferrocenyl ketone-derived tosylhydrazones and H-phosphorus oxides. Followed by the reduction of ferrocene-based phosphine oxides, 1-substituted ferrocene-based p...
Methods for preparation of phosphine oxide, primary and secondary phosphine oxides and secondary diphosphine oxides are described. Characteristic reactions of P–H group, namely, dehydration, hydrophosphination, addition reactions to carbonyl group and Schiff bases, transition-metal-catalyzed cr...
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