Silicon Biological Agents without Carbon Analogy

SILICON BIOLOGICAL AGENTS WITHOUT CARBON ANALOGY 

Most polysiloxanes and cyclosiloxanes possess no biological activity. Up into the late 1960s, it was assumed that all polysiloxane fluids were biologically inert. At that time, the totally unanticipated discovery at Dow Corning Corporation in the United States that some phenyl-con- 

Biological Effects of cis-2,6-Diphe ny Ihexame thy Icy clot etrasiloxane (23) 

Bennett and Le Vier reported that 23 also increases the dopamine content of the brain thus it has possible use in the treatment of Parkinson s syndrome (79). Because of its effect in decreasing the size of the prostate gland, the compound also may have value in the treatment of prostate cancer (80). 

The unique hormonal activity of siloxanes is limited to methylaryl-substituted, linear di- and trisiloxanes and cyclic tri- and tetrasiloxanes (67, 75, 76, 81). In general, at least one arylsilicon grouping is necessary for activity. The substitution of an alkyl group for a phenyl group either decreases the activity markedly or eliminates it entirely. Cyclosiloxanes 

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III. Silicon Biological Agents without Carbon Analogy.288... 

SILICON BIOLOGICAL AGENTS WITHOUT CARBON ANALOGY... 

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