1. Probing the Extremes of Covalency in M–Al bonds: Lithium and Zinc Aluminyl Compounds

2. Covalently modified bacterial polysaccharides and proteins; covalent conjugates of such polysaccharides linked by a Bigeneric spacer, which permits proof of covalency and facilitates purification of conjugated materials, with immunogenic bacterial membrane or other proteins, which conjugates are useful components of bacterial vaccines; and methods of preparing such polysaccharides, proteins