Both diastereoisomers of S-tert-butyl-beta-(trifluoromethyl)isocysteine have been synthesized stereoselectively by the sequential reactions of trifluoroacetimidoyl chloride with the lithium enolate of tert-butyl alpha-tert-butylthioacetate, followed by the diastereoselective reduction of the imino group with sodium borohydride in the presence of zinc(II) or di(ethylene glycol) dimethyl ether, a...

The cell wall lipopolysaccharide of Escherichia coli 011 l-B4 was degraded by (a) acid hydrolysis and (b) by treatment with periodate, followed by reduction with sodium borohydride and mild acid hydrolysis. The various oligosaccharides produced by these procedures were isolated and characterized by chemical and enzymatic methods. Procedure (I released all of the colitose (3,6-dideoxy-~-xylohexo...

The disulfates of unconjugated, and glycineand taurine-conjugated bile acids have been synthesized. Cholic acid derivatives appropriately protected were sulfated with sulfur trioxidetriethylamine complex in pyridine in the usual manner. Subsequent hydrolysis and/or sodium borohydride reduction provided the desired disulfates of cholates in satisfactory yields. Dihydroxy: lated bile acid disulfa...

The cell wall lipopolysaccharide of Escherichia coli 011 l-B4 was degraded by (a) acid hydrolysis and (b) by treatment with periodate, followed by reduction with sodium borohydride and mild acid hydrolysis. The various oligosaccharides produced by these procedures were isolated and characterized by chemical and enzymatic methods. Procedure (I released all of the colitose (3,6-dideoxy-~-xylohexo...

An efficient, general procedure for highly chemoselective reductive mono-alkylation of ammonia with ketones is reported. Treatment of ketones with ammonia in ethanol and titanium(IV) isopropoxide, followed by in situ sodium borohydride reduction, and a straightforward workup afforded primary amines in good to excellent yields. Reductive alkylation of ammonia with aldehydes, on the other hand, a...

A fuel cell operating with aqueous sodium borohydride and hydrogen peroxide streams, with one, two and four cells (electrode area 64, 128 nd 256 cm2) connected in a bipolar mode in a filterpress flow cell is reported. The oxidation of borohydride ion was carried out on Au/C particles upported on a carbon felt electrode while the reduction of hydrogen peroxide was carried out on carbon supported...