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The reaction of N,N-diethyl-2-(dimethylsulfuranylidene)acetamide (1) with protected monosaccharides was extended to a number of O-benzyl- and 4,6-O-benzylidene-d-gluco- and -D-galactopyranose derivatives. Results verified the importance of the protecting group at the hydroxyl on C-2 of the starting 4,6-O-benzylidene-d-glucopyranose. Also, the size of the substituent at C-2 and the presence of a 4,6-O-benzylidene group were found to be essential factors in determining the yield and stereoselectivity of these reactions.

Derivatives of acyclic 3-(polyhydroxylkyl)-alpha,beta-epoxyamides were formed by the reaction of N,N-diethyl-2-(dimethylsulfuranylidene)acetamide with 4,6-omicron-glycopyranoses. The stereoselective synthesis of acylic epoxyamides from acyclic monosaccharide derivatives involves the introduction of two chiral carbons with a substituted asymmetric epoxide group that undergoes regioselective transformation. Furthermore, 2,3-isopropylidene-glucofuranose derivatives produced mainly cyclic C-glycofuranosides.

Stereoselective derivatives of acyclic 3-(polyhydroxyalkyl)-alpha,beta-epoxyamides were produced by the reaction on N,N-diethl-2-(dimethylsulfuranylidene)acetamide with 4,6-O-alkylidene-glycopyranoses. The process generated two new chiral carbons with capacity for regioselective transformation and highly functionalized acyclic structures.

An overview of a series of increasingly complex oxides exhibiting [Cr.sup.4+] in octahedral coordination synthesized from Cr[O.sub.2], under high-pressure and high-temperature conditions is presented. The detailed studies provide insights into the structure, microstructure and electronic and magnetic properties of oxide complexes.