This work concerns the asymmetric addition of methyl propiolate to aldehydes with 1,2-dimethoxyethane (DME) as additive and

The syntheses, characteristics of dinuclear macrocyclic polyamine zinc complexes and their interaction with plasmid DNA are reported. The two cyclen (1,4,7,10-tetraazacyclododecane) moieties are bridged by rigid and flexible linkages. The crystal structures of Zn2C27H43N8O15Cl4 [5c•(ClO4)3•2H2O] and Zn2C30H43N10O13Cl3 [5e•(ClO4)3•H2O] have been determined. The complexes crystallize in the monoclinic space group C2/c and P2(1)/c with the following unit cell parameters: 5c• (ClO4)3 •2H2O: a=32.568(4) Å, b=14.8593(17) Å, c=19.443(2) Å, a=90.00º, b=119.435(4)º, c=90.00º, Dc=1.551 mg/m3, FW=956.71, F(000)=3932; 5e•(ClO4)3 Æ H2O: a=15.807(2) Å, b=16.756(2)Å, c=16.161(2) Å, a=90.00º, b=97.062(4)º, c=90.00º, Dc=1.546 mg/m3, FW=988.83, F(000)=2032. The distance between the two Zn(II) ions is about 4.0 Å. The structures show that two zinc ions can synergistically interact with the substrate DNA. With this novel structural characteristics, the dinuclear macrocyclic polyamine Zn(II) complexes via the synergetic effect between the two zinc ions can catalyze the cleavage of plasmid DNA (pUC18) with unprecedented speed at physiological conditions.

Manganese(III) 5,10,15-tris(tolyl)-20-(4-hydroxyphenyl) porphyrin covalently attached to Merrifield's peptide resin (MPR) was prepared. The catalysts exhibit high reactivity and β-selectivity toward the epoxidation of cholest-5-ene derivatives with PhIO. Under mild reaction conditions, the catalyst was consecutively reused four times without detectable catalyst leaching and gave over 90% epoxide yield and over 99% β-selectivity.

In the presence of a catalytic amount of a simple copper salt, the coupling of imidazole with arylboronic acids was performed in methanol to give corresponding N-arylimidazoles in almost quantitative yields; this coupling reaction could also be performed in aqueous solutions to give N-arylimidazoles in excellent yields.

Novel homochiral molecular tweezers comprised of two chiral macrocyclic polyamine skeletons have been developed. These homochiral artificial receptors exhibit excellent chiral recognition ability toward the enantiomers of L-and D-amino acid derivatives (up to KL/KD=7.9, ΔΔG0=−5.12 kJ mol−1) in CHCl3 at 25.0℃.

Chiral metallomicellar supramolecular systems composed of lipophilic l-histidinol have been investigated for their catalytic activities and enantioselectivities in the hydrolysis of N-protected-amino acid esters. Kinetic evidence suggests that the mechanism of the deacylation promoted by ligand 4a with a hydroxyl group and 2a lacking a hydroxyl group is different. The apparent pKa of Zn2+-4a is 6.8 in the micelllar aggregate. The highest enantioselectivity in hydrolysis of R(S)-C12-Leu-PNP (kS/kR=3.01) was obtained with 4a-Zn2+ as catalyst.

Four new long chain alkyl substituted 2,6-dioxo-1,4,7,10-tetraazacyclododecanes bearing an alcohol pendant has been synthesized. They coordinate with metal ion (Zn2+, Cu2+, Ni2+, Co2+) to yield 1:1 five-coordinate complexes. The catalytic properties of these complexes have been investigated for the hydrolysis of bis(p-nitrophenyl) phosphate (BNPP) in comicellar solution. The alcohol pendant has a profound effect on the catalytic properties of macrocyclic complexes, and the nature of transition metal ion, micellar microenvironment, hydrolysis temperature, hydrophobic interactions between the metallocatalyst and substrate are also important factors in the hydrolysis ofBNPP. Under the physiological conditions (pH=7.41, 35±0.1◦C), the complexes exhibit higher catalytic activity (up to over 2-3 orders of magnitude) than metal ion or ligand alone in the hydrolysis of BNPP in comicellar solution with 2mM Brij 35.

Novel chiral imidazole cyclophane receptors were synthesized by highly selective N-alkylation of the imidazolyl 1Nposition of the bridged histidine diester 2 with the dibromide in the presence of NaH; these receptors exhibit good chiral recognition toward the enantiomers of L-and D-amino acid derivatives (up to KD/KL=3.52, DDG0=23.11 kJmol21) in CHCl3 at 25.0℃.

Carbonyl ruthenium(Ⅱ) 5,10,15-tris(4-R-phenyl)-20-(4-hydroxyphenyl)porphyrins (R) Cl, Me) covalently attached to Merrifield's peptide resin were prepared. The catalyst with R) Cl was found to efficiently catalyze Cl2pyNO epoxidation of a wide variety of alkenes, including aromatic and aliphatic terminal alkenes, cis-and trans-stilbene, cyclohexene and cyclooctene, R,â-unsaturated ketones, conjugated enyne, glycal, and protected R-amino alkene. Unusual selectivities were observed for the epoxidations of 1,5-cyclooctadiene, cis-1-phenyl-3-penten-1-yne (9), 3,4,6-tri-O-acetyl-D-glucal (11), and 2-(Boc-amino)-1-phenylbut-3-ene (13), which feature a complete bisepoxide selectivity (1,5-cyclooctadiene), unprecedentedly high cis:trans ratio (9), and complete diastereoselectivity (11 and 13). The new heterogenized metalloporphyrin epoxidation catalysts are of high stability and reusability.

Amidation of a variety of hydrocarbons with PhIdNTs catalyzed by ruthenium and manganese meso-tetrakis(pentafluorophenyl)porphyrins 1 and 2 afforded N-substituted amides in up to 92% yields with good to excellent substrate conversions. By employing catalyst 2, exceptionally high turnovers (up to 2600) were achieved, and the amidations can be effected by directly using PhI(OAc)2/NH2R as amidating reagents; in the case of R) COCF3 a direct amination was realized in up to 90% yield.