Low Pressure Ethenolysis of Renewable Methyl Oleate in a Microchemical System

A microchemical system for ethenolysis of renewable methyl oleate was developed, in which the dual-phase, microfluidic design enabled efficient diffusion of ethylene gas into liquid methyl oleate through an increased contact area. The increased mass transfer of ethylene favored the formation of desired commodity chemicals with significantly suppressed homometathesis when compared to the bulk system. In addition to higher selectivity and conversion, this system also provides the typical advantages of a microchemical system, including the possibility of convenient scale-up

Synthesis of side chain-modified iodothyronines. Synthesis and structure-activity relationships (SARS) of galanthamine derivatives. Total synthesis of (+)-valyldetoxinine. Synthesis and mechanism of cyclic acetal and ketal formation in pentono-1,4-lactones

New side chain-modified iodothyronines have been synthesized. They include: 1- (4-(4-hydroxyphenoxy)-3,5-diiodo-phenyl) -1,2-ethanediol(T\sb2 EG); $\alpha$-hydroxy-4-(4-hydroxyphenoxy)-3,5-diiodobenzeneacetic acid (T\sb2HAA) and their 4-methylether derivatives (MT\sb2EG, MT\sb2HAA); 1- (4-(hydroxyphenoxy)-3,5-diiodo-phenyl) -2-aminoethanol (T\sb2EA); 1- (4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl) -1,2-ethanediol (T\sb3EG); 1- (4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl) -2-aminoethanol (T\sb3EA); and $\alpha$-hydroxy-4-(3-iodo-4-hydroxyphenoxy)-3,5-diiodobenzeneacetic acid (T\sb3HAA). The synthesis and structure-activity relationships (SARs) of galanthamine derivatives are examined. Structural studies of the alkaloid galanthamine, a cortical acetylcholinesterase (AChE) inhibitor, and its salt, galanthamine methiodide, were carried out both in solution and in the solid state, using spectroscopic methods. Structural and pharmacological studies of nineteen analogs of galanthamine were conducted. Systematic derivatization of galanthamine at the cyclohexene ring, tertiary amino, hydroxyl and methoxyl functions indicated that these structural features are essential for biological activity. One derivative, galanthamine n-butyl carbamate, had an LD\sb{50} of over 100 mg/kg (i.p.) in mice. In a passive avoidance paradigm, this analog improved performance in a dose-dependent fashion with a peak effect at 0.1 mg/kg in control and 0.5 mg/kg in basal forebrain lesioned mice. With the surprisingly high therapeutic ratio, this compound may be of interest in treating cholinergic deficits of the central nervous system such as Alzheimer\u27s disease. The total synthesis is described of (+)-valyldetoxinine, a member of the detoxin complex, metabolites produced by Streptomyces caespitosus var. detoxicus 7072 GC\sb1. The detoxin complex is a selective antagonist of the antibiotic blasticidin S. The total syntheses of (+)-valyldetoxinine and (2R,3S,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine hydrochloride, a very potent competitive inhibitor of an $\alpha$-galactosidase and a moderate inhibitor of an $\alpha$-mannosidase, were both completed. (Abstract shortened with permission of author.

Synthesis of side chain-modified iodothyronines. Synthesis and structure-activity relationships (SARS) of galanthamine derivatives. Total synthesis of (+)-valyldetoxinine. Synthesis and mechanism of cyclic acetal and ketal formation in pentono-1,4-lactones

New side chain-modified iodothyronines have been synthesized. They include: 1- (4-(4-hydroxyphenoxy)-3,5-diiodo-phenyl) -1,2-ethanediol(T\sb2 EG); $\alpha$-hydroxy-4-(4-hydroxyphenoxy)-3,5-diiodobenzeneacetic acid (T\sb2HAA) and their 4-methylether derivatives (MT\sb2EG, MT\sb2HAA); 1- (4-(hydroxyphenoxy)-3,5-diiodo-phenyl) -2-aminoethanol (T\sb2EA); 1- (4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl) -1,2-ethanediol (T\sb3EG); 1- (4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl) -2-aminoethanol (T\sb3EA); and $\alpha$-hydroxy-4-(3-iodo-4-hydroxyphenoxy)-3,5-diiodobenzeneacetic acid (T\sb3HAA). The synthesis and structure-activity relationships (SARs) of galanthamine derivatives are examined. Structural studies of the alkaloid galanthamine, a cortical acetylcholinesterase (AChE) inhibitor, and its salt, galanthamine methiodide, were carried out both in solution and in the solid state, using spectroscopic methods. Structural and pharmacological studies of nineteen analogs of galanthamine were conducted. Systematic derivatization of galanthamine at the cyclohexene ring, tertiary amino, hydroxyl and methoxyl functions indicated that these structural features are essential for biological activity. One derivative, galanthamine n-butyl carbamate, had an LD\sb{50} of over 100 mg/kg (i.p.) in mice. In a passive avoidance paradigm, this analog improved performance in a dose-dependent fashion with a peak effect at 0.1 mg/kg in control and 0.5 mg/kg in basal forebrain lesioned mice. With the surprisingly high therapeutic ratio, this compound may be of interest in treating cholinergic deficits of the central nervous system such as Alzheimer\u27s disease. The total synthesis is described of (+)-valyldetoxinine, a member of the detoxin complex, metabolites produced by Streptomyces caespitosus var. detoxicus 7072 GC\sb1. The detoxin complex is a selective antagonist of the antibiotic blasticidin S. The total syntheses of (+)-valyldetoxinine and (2R,3S,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine hydrochloride, a very potent competitive inhibitor of an $\alpha$-galactosidase and a moderate inhibitor of an $\alpha$-mannosidase, were both completed. (Abstract shortened with permission of author.