Sang Woo Park

Synthesis of new pyrrolidine C-nucleosides via Staudinger-aza-Wittig cyclization of γ-azido ketone

Abstract Novel N -acetyl C -aza-2-deoxy- d -ribonucleosides were synthesized from 2-deoxy- d -ribose via a consecutive procedure of the addition of ortho-lithiated pyrimidine salt, Staudinger-aza-Wittig ring cyclization, and reduction of cyclic imine.

A total synthesis of (−)-reiswigin a via sequential claisen rearrangement-intramolecular ester enolate alkylation

Abstract (−)-Reiswigin A ( 1 ), a novel anti-viral diterpene, has been synthesized in a highly stereoselective manner utilizing a sequential Claisen rearrangement — intramolecular ester enolate alkylation strategy.

Synthesis and biological properties of new 1β-methylcarbapenems having tetrazolothioether moiety

The synthesis and biological activities of a series of new 1beta-methylcarbapenems 1a-l having tetrazolothioether moiety at C-5 position of pyrrolidine were described. Among these compounds, 1c showed the most potent antibacterial activity and advanced pharmacokinetics compared with imipenem and meropenem.

Synthesis and biological properties of new 1β-methylcarbapenems containing heteroaromatic thioether moiety

The synthesis and biological activities of a series of new 1beta-methylcarbapenems 1a-h having heteroaromatic thioether moiety at C-5 position of pyrrolidine were described. Among these compounds, 1,2,3-thiadiazole derivative 1h showed the most potent antibacterial activity and advanced pharmacokinetics in comparison with meropenem.

Synthesis and biological activity of 1β-methyl-2-[5′-isoxazoloethenylpyrrolidin-3′-ylthio]carbapenems

A new series of 1beta-methylcarbapenems 1a-i bearing isoxazoloethenyl groups on the pyrrolidine ring has been prepared and evaluated for in vitro antibacterial activity and stability to DHP-I. Most compounds showed excellent antibacterial activity and high stability to DHP-I superior to that of meropenem. Of these new carbapenems, 1a,b,h exhibited the best combination of antibacterial activity and DHP-I stability.

Monoazo disperse dyes containing ethyleneimine moieties Part 1: Synthesis and application of some monoazo disperse dyes derived from 3-amino-4-methoxyacetanilide

Abstract Three aminoazobenzene disperse dyes containing a terminal ethyleneimine group derived from 3-amino-4-methoxyacetanilide were synthesised using Gabriel and Wenker’s method. One aminoazobenzene disperse dye containing a terminal N -hydroxyethylene group as a hydrolysed form and another azo disperse dye containing a terminal N -dihydroxyethylene group were also synthesised. The colour properties of these five dyes in acetone were investigated. As expected, attachment of the ethyleneimine ring to the terminal N -atom resulted in hypsochromic shifts and decreasing ϵ max values when compared with analogous compounds containing terminal N -hydroxyethyl and N , N -dihydroxyethyl groups. When one or two chloro substituents were attached on the diazo component of the aziridinyl azo disperse dyes, colour and fastness properties were affected. The rate of hydrolysis of three ethyleneimine dyes was investigated. ©

Synthesis and biological properties of new 1β-methylcarbapenems

The synthesis and biological activity of the novel series of 1 beta-methylcarbapenems, 1 and 2 were described. Most compounds displayed high potent antibacterial activity. The best compound in this series, 2a (IH201; R2 = NH2) showed an excellent and a broad spectrum as well as high renal DHP-I stability. It also possessed good in vivo efficacy and high safety.

SOLID-PHASE SYNTHESIS OF 2,4,6-TRIAMINOPYRIMIDINES

A novel method for polymer-supported synthesis of 2,4,6-triaminopyrimidines 1a–h on the basis of sequential nucleophilic substitution of appropriate amines to pyrimidine template is described.

Synthesis and anti-inflammatory and analgesic activities of phenoxyalkanoic acid derivatives

The synthesis of phenoxyalkanoic acid derivatives and their anti-inflammatory and analgesic activities are described. Analysis of structure-activity relationships shows that in trichlorophenoxy derivatives anti-edematous potency is associated with the presence of 1-thiopropyl moiety and 2 or 4-aminopyridyl moiety at R′ position contributes to the analgesic activity.

Inhibitory effect of pyridyloxy‐ or phenoxylphenoxyalkanate derivatives on rat lens aldose reductase and rat platelet aggregation

The therapeutic potential of aldose reductase inhibitors for the prevention of the secondary complications of diabetes has been extensively reported. On the other hand, the hyperaggregability of platelets in diabetic patients has also been reported as a cause of chronic diabetic complications. The purpose of this study was to develop new compounds with these dual effects from pyridyloxy‐ or phenoxylphenoxyalkanate synthesized derivatives and examine the effect of their structure‐activity relationships on the inhibition of rat lens aldose reductase (RLAR) as well as on platelet aggregation. 2‐[4‐(2,6‐dichloro‐3‐methyl‐phenoxy)‐3‐nitro‐phenoxy]‐propionic acid (3) exhibited the most potent inhibitory effect (IC50 = 3.0 ± 0.21 μM), comparable to tetramethylene glutaric acid (IC50 = 6.1 ±0.2 μM), which is used as a positive control on RLAR, and showed potent inhibitory activities on rat platelet aggregation induced by ADP and collagen (IC50 = 0.093 ± 0.01 and 0.032 ± 0.01 μM, respectively) comparable with aspirin (IC50 = 0.15 ± 0.05 and 0.047 ± 0.01 μM, respectively), used as a positive control.