Polymers, osmium carbohydrate

Osmium Carbohydrate Polymers as Potential Antiarthritic Drugs... 

New osmium compounds may prove to be antiinflammatory agents useful in the treatment of some forms of arthritis. The materials are osmium-carbohydrate polymers (1), termed osmarins. These compounds bind irreversibly with living tissue and exhibit other properties which suggest their use. 

In this paper, we first present the preparation and characterization of osmium-carbohydrate polymers. This discussion is followed by a review of our studies involving animals. Mice have been used for toxicity screening, and we have examined the effect of osmarins upon the tissues of the synovial space in both pigs and rabbits. Finally, we report the results of a small number of experimental treatments of arthritic dogs. 

Surprisingly, OSO4 has been found to be an effective treatment for inflammatory arthritis of the knee. This application of osmic acid was approved in Sweden and Norway in 1978, but its use is controversial. The potential of damage from the OSO4 to healthy tissue has prompted a search for other osmium derivatives. Work is being done on osmium carbohydrate polymers to avoid the potential side ef-... 

C. C. Hinckley, J. N. BeMiller, L. E. Strack, and L. D. Russell Osmium Carbohydrate Polymers as Potential Antiarthritic Drugs (Platinum, Gold and Other Metal Chemotherapeutic Agents, ACS Symposium Series v. 209, Ed. S. J. Lippard), p. 421. ACS, Washington (1983). 

Some other natural compounds have been transformed for their use in the synthesis of polymers via olefin metathesis processes. As mentioned in the introduction, furans, which are obtained from carbohydrates, are perfect precursors of monomers for ROMP via simple Diels-Alder cycloadditions (n) (Scheme 25) [26]. In this regard, the first example of the ROMP of 7-oxabicyclo[2.2.1]hept-5-ene derivatives was reported by Novak and Grubbs in 1988 using ruthenium- and osmium-based catalysts [186]. The number of examples of ROMP with monomers with this generic structure is vast, and it is out of the scope of this chapter to cover all of them. However, it is worth mentioning here the great potential of a renewable platform chemical like furan (and derived compounds), which gives access to such a variety of monomers. 

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