The synthesis of a new methylene−(vinyl alcohol) copolymer, poly((vinyl alcohol)2-alt-methylene) (MVOH), by ring-opening metathesis polymerization with ruthenium catalysts is reported. Unsaturated cyclic 1,3-diols were protected with a di-tert-butylsilyl group to form strained cyclic olefins. The molecular weights of the polymers were controlled by varying the monomer-to-catalyst ratios or by the addition of a chain transfer agent. Hydrogenation and subsequent deprotection of the ROMP polymers yield the MVOH copolymer structure which was confirmed by 1H NMR and 13C NMR spectroscopies. Thermal properties of the corresponding MVOH copolymer are reported.

No abstract

Many human carcinomas overexpress the Lewis(y) (Le[y]) blood-group epitope [Fucalpha1-->2Galbeta1-->4 (Fucalpha1-->3)GlcNAcbeta1-->3Gal-]. With a view to developing Le(y) based vaccines we have examined the immunogenicity of Le(y)-protein conjugates in mice. Le(y) pentasaccharide was synthesized as its allyl glycoside and coupled to keyhole limpet hemocyanin (KLH) by reductive amination or by a novel method utilizing a maleido-derivitized alkyl carboxyhydrazide as a bridging group to 2-iminothiolane-derivitized KLH. Le(y) oligosaccharide was also coupled to bovine serum albumin by reductive amination. Immunization of groups of mice with the three conjugates, together with the immunological adjuvant QS21, showed that Le(y) oligosaccharide directly coupled to KLH was the most efficient conjugate for eliciting IgG and IgM antibody responses to naturally occurring forms of Le(y) epitopes carried on mucins and glycolipids. These antibodies were also reactive with and cytotoxic to a human breast cancer cell line expressing Le(y) (MCF-7). These experiments suggest that Le(y)-KLH antigen and QS21 adjuvant could be considered as an immunogenic therapeutic vaccine in carcinoma patients.

A concise and potentially practical synthesis of the title compound has been achieved. The route features a high degree of convergence and economy of synthetic operations. A key step is the concurrent introductory addition of three R-L-fucosyl residues at required hydroxyl acceptor sites (see 37 f 39). Conjugation to carrier protein was achieved, and a route to include truncated structures for investigations for antibody specificity was accomplished.