NEW MATERIAL: A peptide derivative of formula I [R1 is a (substd.) aryl, (substd.) aralkyl, etc.; R2 is a divalent residue derived from proline of formula II, etc.; R3 is H or a C1-4 alkyl; R4 is a C1-5 alkyl, the side chain of an α-amino acid; R5 and R'5 are each H, a metal, C1-5 alkyl, benzyl, etc.]
USE: Useful as therapeutic agents for periodontitis or dental infections, and as protectants for leather, gelatin, etc.
PROCESS: For example, dibenzyl phosphite is reacted with sodium hydride in DMF under cooling and phenylethyl bromide, etc., is added to give dibenzylphenylethyl phosphonate. The product is reacted with phosphorous pentachloride in benzene to give a corresponding chloride, which is then reacted with a peptide wherein the functional group of the side chain and the C-terminal carboxyl group are protected. Deprotection of the product with a Pd catalyst gives the peptide derivative of formula I.
FURABUIO TOMA
ATANASUIO IOTAKI
