PREPARATION OF FUNCTIONALIZED ETHERS OF CYCLOSPORINE-A

Cyclosporin A (1) was O-alkylated selectively using phase transfer cat alyzed reactions. With allyl chloride, metallyl chloride and propargyl bromide this lead to the ethers 2, 3 and 4, respectively. With t-buty l bromoacetate the product was the ester 5 which was reduced to the al cohol 6. With 2-(bromomethyl-propenoic acid methyl ester the ether 7 w as obtained which was converted to 8. The allylic ether alcohol 10 was prepared from 9. This in turn was accessible from 1 and 1-chloro-2-ch loromethyl-2-propene.