The asymmetric reduction of aromatic and aliphatic ketones, halogeno ketones, hydroxy ketones, keto esters, and ketone oxime ethers with reagents prepared from borane and chiral amino alcohols has been investigated. When a,a-diphenyl-P-amino alcohols, such as (2S,3R) -( -) -2-amino-3-methyl-1,ldiphenylpentanol (2d), were used as a chiral auxiliary, very high enantioselectivities (ca. 90% e.e.) were obtained in the reduction of various ketones and oxime ethers.

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A specific, sensitive and easily performed method for the determination of gangliosides in tissue was developed. After removal of water-soluble compounds, total lipids were extracted from tissue and then treated with 2,4-dinitrophenylhydrazine hydrochloride and dicyclohexylcarbodi-imide in dimethylformamide at 0 degrees C to form ganglioside hydrazides. After removal of excess reagents by column chromatography on silicic acid, the ganglioside 2,4-dinitrophenylhydrazides were eluted from the column and analysed by h.p.l.c. with the use of a silica-gel normal-phase column eluted with an isocratic chloroform/methanol/water/acetic acid system. The addition of CaCl2 improved the separation of GM3 ganglioside containing N-acetylneuraminic acid from that containing N-glycollylneuraminic acid. 2,4-Dinitrophenylhydrazide peaks were measured by the absorbance at 342 nm. Quantification of GM3, GM2, GM1, GD1a, GD1b, GT1b and LM1 gangliosides was linear in a range 0.02-1.6 nmol. GM4, GD3, GT1a and GQ1b gangliosides also yielded distinct peaks, although the range of linearity was not examined. This method was applied to the analysis of the total lipids of rat brain and hepatocytes.

Laser-chemical vapor deposition (LCVD) of elemental selenium onto the surface of several metals (Ag, Cu, Cd, Zn, Mg, Sn) has been achieved using photolytic decomposition of diethyl selenium, and the interaction between the deposited selenium coatings and the metal surface has been examined by X-ray photoelectron spectroscopy, Raman spectroscopy, X-ray diffraction, and electron microscopy. It is revealed that thin coatings of Se take part in a solid-state chemical reaction with Ag, Cd, Cu, Mg, and Zn substrates and demonstrated for the first time that the reaction between amorphous selenium and these metals (and not only Cu) does not require high temperatures but takes place at room temperature. The results reveal the feasibility of room-temperature selenization of metals.